The Fourth Industrial Revolution

Technology has revolutionized the way our world goes about its work. Since the turn of the millennium, everything has been influenced and changed courtesy of technology. But, at this moment in time, the world is on the verge of experiencing a bigger industrial revolution. A revolution that will bring the planet closer and therefore requires a vital and comprehensive input from everyone including the public sector, private sector, civil society and the academic world.

1 2 3 4 industrial revolution

 

Production during the First Industrial Revolution was powered by the use of water and steam. The Second Revolution witnessed an up gradation to electricity. The Third went one better and made use of electronics and information technology (IT) for enhanced manufacturing and production. The latest and the Fourth in the lines of revolutions is using the essence of the Third and digitizing it. This will help in integrating the physical, digital and biological world.

The Fourth revolution which is the fastest growing as compared any of the last three is primarily because of three reasons, velocity, scope, and system. The betterment witnessed in this revolution is not only influencing every industry but also altering the entire production, management and governance systems in those industries.

The new revolution would open further possibilities of the entire globe becoming one large market through smartphones that possess a powerful processing power, unlimited storage capacity and ease of access to knowledge. Moreover, the revolution would be further strengthened by the emergence of artificial intelligence (AI), Wearables on Internet of Things and self-driving vehicles and advancement in various technologies such as bio, Nano, quantum etc.

AI is already on the up and the results are there for everything to see. From drones to virtual assistants, from translation software to self-driving cars, the scope is limitless. The progress in AI is triggered by an enhanced computing power and availability of data. This data is derived from software that is highly potent in discovering anything from new drugs to predicting our cultural interests. From engineers to designers to architects, everyone is making the most of the digital technology through activities such as computational designs and synthetic biology to initiate a combination between humans and everything attached to them.

Challenges and Opportunities

The Fourth Revolution has the ability, alike previous revolutions, to better the financial strength and quality of life of the masses. Up until now only the affording consumers that had access to the digital world have been able to improve their life’s efficiency and style by making the most of the current upsurge. The latest digital products and services such as booking of flights, paying online, shopping from online stores, listening to music, etc. has been few of the byproducts of the digital revolution that are being used.

On a larger front, technological innovations will also help in assisting supply chain mechanism through greater efficiency, effective productivity, lower logistics cost and faster communication. With the entire trade cost decreasing, penetration in new markets and improvement in economic growth would be imminent.

On the contrary, various economists such as Erik Brynjolfsson and Andrew McAfee target the digital revolution to cause greater inequality in the labor market as the machine would replace humans. They also argue that it would lead to major labor disruption and displacement. However, it can also be viewed differently as the revolution may lead to an increase in more safe, specialized and rewarding jobs.

The future picture will become clear with time and either one or a combination of both those possibilities may be correct. But, one thing is for certain, the future labor market would become more talent orientated than capital orientated. Meaning that the defining factor for production would be labor and not capital. Moreover, this trend would widen the socioeconomic and inequality gap between the lowly skilled and lowly paid against the highly skilled and highly paid.

Additionally, the socioeconomic gap may as well be the only adverse effect of the Fourth Revolution. Up until now the biggest beneficiaries of technological innovations have been the various stakeholders of intellectual and physical capital. This has predominately increased the gap between capital and labor-orientated markets. The ever increasing bridge between the skilled and unskilled workers is more evident than ever before especially in terms of earnings. And it has mainly resulted in majority countries to have faced a southwards trend when it comes to incomes. Furthermore, the highly skilled and unskilled are still in demand but the middle population is facing a lack of demand.

This growing trend is igniting a fear factor among the middle class for their financial future and the future of their coming generations. They are also disappointed by the treatment laid towards them by the corporations and government as this ultra-fast and highly income economy has very little for the ever-growing middle class. Another factor for the dissatisfaction is the generalization of digital technology and the usage of social media forums. The popularity of social media has given an ideal opportunity for cross culture integration but in reality, it has raised unreal and false expectations about individual and company success. It has also become the forum for spreading of high-end ideas and ideologies which have frustrated the non-accomplishing middle class.

The Impact on Business

One thing that all global CEOs, top-level business official and even the most connected ones agree upon is the uncertainty regarding the pace at which innovation would accelerate or the pace or numbers at which it will face disruptions. But, in all this madness, one thing is for sure that technologies that are driving the Fourth Revolutions are working wonders for businesses all around the world.

While the new technological innovations are assisting companies in fulfilling current supply needs in a more proficient way, it is also disrupting the already existing industry supply value chains. To add to the disruption vows, the proactive industry competitors are using the global digital market for better research, development, marketing, sales and distribution techniques to dislodge well-established businesses. And they are doing it faster than ever before with help of improved quality, speed and price factors.

On the demand side, the shift is mainly due to change consumer behavior patterns and increasing options which are handed to them courtesy of the brilliance of smartphones. This has prompted companies in quick adaption to the new consumer choices and delivering products and services accordingly.

The latest and modern technological platforms, that smartphones have made easy to access, are providing the adequate forum for demand to meet supply. This is resulting in the creation of new ideas regarding delivering and consumption of goods which in turn is also disrupting the existing industry norms. These platforms that are constantly transforming one industry after the other and has also made it easy for individuals and businesses to improve their financial prowess. It is because today they faces fewer barriers to progress and it is changing the professional world for good.

The Fourth Revolution is responsible for having four major effects on four aspects of businesses starting from customer service to product development to collaborative innovation and lastly to organizational structures. Customers, that remain the focal point for companies, are continuously being served in a more professional manner. Digital enhancement is constantly improving the quality, value and durability of product and service, besides introducing ways of their better maintenance. The fast improving digital industry that is experiencing top quality changes in customer experiences, data-based services and performance is prompting companies to work in tandem to find solutions. Lastly, the emergence of global entities and advanced business structures is forcing companies to modify the definition of talent, culture, and organizational structure.

The conclusion suggests that companies and its leadership need to redefine the way they do business by regularly innovating and challenge the benchmark of the industry. This is mainly because the fourth revolution is far more advanced in terms of technology as compared to the third which only experienced simple technological inventions.

The Impact on Government

With the help of new technological platforms, citizens will be able to interact with the government in a healthier way. They will be able to lodge complaints, give suggestions and welcome feedback. On the other hand, governments to use other technological products and services such as contemporary surveillance systems to control and keep a better eye on the masses. These new developments will also continuously force the governments to change their public policy and approach and also distribute their power to their subordinates in a more proficient manner. At the end, the defining factor would be government and public offices’ ability to adapt to fast paced changes. If they can, then they would be able to blossom through transparency and improved efficiency but if they cannot, they will face increasing pressure.

The system followed by the governments and public offices dates back to the Second Revolution. They still believe in assessing the problem, devising a strategic response and then making the decision. In other words, they follow a strict and steady top to down approach. But, the Fourth Revolution is everything but slow. Therefore in order to cope up with the pace of the current global movement, legislators, and regulators need to rework their strategy because at things stands, they are falling behind problematically.

The question that arises is, can governments safeguard the interests of the public and also support technological advancement at the same time? The answer is yes but only through adopting swift response approach to the massive changes in software engineering and business structure, similar to private sectors. Hence, government and regulators need to learn to regulate by constantly reinventing their approach as per the technological forward movement and also by working hand in hand with the private sector and civil society.

The fourth revolution will also lead to a new type of security threat. As history suggests, technological advancements have been the backbone of wars. Today, the matter is slightly different yet more complex. Countries are combining traditional warfare techniques with elements that are uncommon to get an upper hand. This has led to a situation where distinguishing between wartime and peace, actual war and cyberwar is becoming difficult.

While, these developments may result in countries and terrorist groups in having the ability to cause mass scale destructions through modern weapons, countries can use the very same technology to protect themselves and nullify or limit the impact of that destruction. It has become a two-way road that allows for new ways of protection and also bull’s eye precision in targeting.

The Impact on People

The impact of the fourth revolution does not end there. It is and will continue to impact us as humans alongside impacting our lifestyles, our relationships, the way we perceive certain things and the way we work and enjoy life. it is already changing medical science and the list of the number of things it can affect may never end. While being passionate about technology and welcoming it into one’s life is necessary but one thing is for sure, it will affect the way the world resides, loves and corporates. For example, the way this world relates to smartphones these days can surely cutting the core essence of relationship and self-reflection.

The world understands the importance of privacy but this technology keeps forcing us to get tracked through the information we share for enhanced connectivity purposes. This lack of control over our privacy would only increase in the coming years. Moreover, the progress in the fields of biotech and AI will redefine the limits of human capabilities and also reconstruct our moral and ethical boundaries.

Focusing on the future

The fourth revolution is nurturing and prospering in front of our eyes, therefore, we have to take responsibility for its evolution and the part we play in it. Thus, it is important that we only guide it a better way so that it benefits us and our future generations.

This can only be done through constructing a global view of the ways in which technology must reshape our world and the things in it. Technology is our greatest asset and greatest threat so we must give it timely attention and strategic thinking. Instead, we are busy in resolving the petty issues surrounding our world.

To conclude the argument, the important factor still remains people and their values. The world needs to prioritize humans and their empowering above anything else. The worst impact of the fourth revolution can be the transforming of humans into robots with no heart or soul. But, its best effect can be the uplifting of humans and their values based on the shared view of a better future. And as humans, we must believe the latter would prevail.

Maximum Hydraulic Component Life

Defining Fluid Temperature & Viscosity Limits for Maximum Hydraulic Component Life

By Brendan Casey

Many factors can reduce the service life of hydraulic components. Incorrect fluid viscosity is one of these factors. To prevent low (or high) viscosity from cutting short component life, an appropriate fluid operating temperature and viscosity range must first be defined and then maintained on a continuous basis. Before I discuss this in detail, let me explain the interrelationship of fluid temperature and viscosity, and how they impact upon hydraulic component life.

Temperature/Viscosity Relationship of Hydraulic Fluid

The viscosity of petroleum-based hydraulic fluid decreases as its temperature increases and conversely, viscosity increases as temperature decreases. This is why limits for fluid viscosity and fluid temperature must be considered simultaneously. Low fluid viscosity can result in component damage through inadequate lubrication caused by excessive thinning of the oil film, while excessively high fluid viscosity can result in damage to system components through cavitation.

Manufacturers of hydraulic components publish permissible and optimal viscosity values, which can vary according to the type and construction of the component. As a general rule, operating viscosity should be maintained in the range of 100 to 16 centistokes (460 to 80 SUS), however viscosities as high as 1000 centistokes (4600 SUS) are permissible for short periods at start up. Optimum operating efficiency is achieved with fluid viscosity in the range of 36 to 16 centistokes (170 to 80 SUS) and maximum bearing life is achieved with a minimum viscosity of 25 centistokes (120 SUS).

Hydraulic Fluid Viscosity Grades

ISO viscosity grade (VG) numbers simplify the process of selecting a fluid with the correct viscosity for a system’s operating temperature range. A fluid’s VG number represents its average viscosity in centistokes (cSt) at 40°C. For example, an ISO VG 32 fluid has an average viscosity of 32 centistokes at 40°C. Note that the average fluid viscosity of ASTM and BSI viscosity grade numbers are measured at 100°F (38.7°C). This means that fluids of a given ASTM or BSI grade are slightly more viscous than the corresponding ISO grade.

Determining the Correct Viscosity Grade

In order to determine the correct fluid viscosity grade for a particular application, it is necessary to consider: ” starting viscosity at minimum ambient temperature; ” maximum expected operating temperature, which is influenced by maximum ambient temperature; and ” permissible and optimum viscosity range for the system’s components.

In most cases, the machine manufacturer will specify the correct viscosity grade. It is important to understand that the machine manufacturer’s recommended viscosity grade should change as the ambient temperature conditions in which the machine operates change.

I say this because several years ago I was involved in the analysis of several premature component failures from a mobile hydraulic machine. The machine was designed and built in the Northern Hemisphere, but was operating in high ambient air temperatures in the Southern Hemisphere. The components had failed due to inadequate lubrication, because of low fluid viscosity.

Investigation revealed that the fluid in the system was ISO VG 32. While this viscosity grade is suitable for cooler climates found in parts of the Northern Hemisphere, it was not suitable for the high ambient temperatures in which this machine was operating. The machine owner confirmed that the manufacturer’s fluid recommendation was indeed ISO VG 32.

The machine manufacturer had not altered their fluid viscosity recommendation to take into account the higher ambient temperatures in which this particular machine was operating. This oversight resulted in several premature component failures because of low fluid viscosity.

The machine manufacturer’s viscosity grade recommendation can be checked using the viscosity/temperature diagram shown in exhibit 1, assuming the minimum starting temperature and the hydraulic system’s maximum operating temperature are known. For example, let’s consider an application where the minimum ambient temperature is 15°C, the system’s maximum operating temperature is 75°C, the optimum viscosity range for the system’s components is between 36 and 16 centistokes and the permissible, intermittent viscosity range is between 1000 and 10 centistokes.

fluid-viscosity

From the viscosity/temperature diagram in exhibit 1 it can be seen that to maintain viscosity above the minimum, optimum value of 16 centistokes at 75°C, an ISO VG 68 fluid is required. At a starting temperature of 15°C, the viscosity of VG 68 fluid is 300 centistokes, which is within the maximum permissible limit of 1000 centistokes at start up. If the machine manufacturer’s recommendation was ISO VG 32 fluid under the same conditions, I would question it.

A word of warning here – do not change the fluid viscosity grade in a system without consulting the equipment manufacturer. Doing so may void the manufacturer’s warranty and/or cause damage to the system’s components.

Defining Operating Temperature Limits

Having established that the fluid in the system is the correct viscosity grade for the ambient temperature conditions in which the machine is operating, the next step is to define the fluid temperature equivalents of the optimum and permissible viscosity values for the system’s components.

By referring back to the viscosity/temperature curve for VG 68 fluid in exhibit 1, it can be seen that an optimum viscosity range of between 36 and 16 centistokes will be achieved with a fluid temperature range of between 55°C and 78°C. The minimum viscosity for optimum bearing life of 25 centistokes will be achieved at a temperature of 65°C. The permissible, intermittent viscosity limits of 1000 and 10 centistokes equate to fluid temperatures of 2°C and 90°C, respectively.

Going back to our example, this means that with an ISO VG 68 fluid in the system, the optimum operating temperature is 65°C and maximum operating efficiency will be achieved by maintaining fluid temperature in the range of 55°C to 78°C. If cold start conditions at or below 2°C are expected, it will be necessary to pre-heat the fluid to avoid damage to system components. Intermittent fluid temperature in the hottest part of the system, which is usually the pump case, must not exceed 90°C.

Note that fluid temperatures above 82 C (180 F) damage seals, reduce the service life of the hydraulic fluid and in most cases, will cause the viscosity limits of the fluid to be exceeded. This means that the operation of any hydraulic system at temperatures above 82 C (180 F) is detrimental and should be avoided.

Preventing Damage Caused by High Temperature Operation

To prevent damage caused by high fluid temperature and/or low fluid viscosity, a fluid temperature alarm should be installed in the system and all high temperature indications investigated and rectified immediately. The over-temperature alarm should be set to the temperature at which the minimum, optimum viscosity value is exceeded. As already explained, this will be dependent on the viscosity grade of the fluid in the system. In the example discussed above, the fluid temperature alarm would be set at 78°C.

Continuing to operate a hydraulic system when the fluid is over-temperature is similar to operating an internal combustion engine with high coolant temperature. Damage is almost guaranteed. Therefore, whenever a hydraulic system starts to overheat, shut down the system, find the cause of the problem and fix it!

About the Author: Brendan Casey has more than 15 years experience in the maintenance, repair and overhaul of mobile and industrial hydraulic equipment.

OEE – Overall Equipment Effectiveness

Oh “Equipment Effectiveness”, I’ve heard about that before! 

Unfortunately, in many facilities, that’s all OEE (Overall Equipment Effectiveness) is to the personnel. Something they heard of, talked about or read about. Many maintenance departments today still do not effectively utilize the OEE tool even though it’s widely used among the world class companies.

Definition of OEE: Overall Equipment Effectiveness

The overall performance of a single piece of equipment or even an entire factory, will always be governed by the cumulative impact of the three OEE factors: Availability, PerformanceRate and Quality Rate.

 

OEE is a percentage derived by multiplication of the three ratios for the factors mentioned above. The OEE percentage is used for analysis and benchmarking.

In speaking with Mike Sondalini (Best Practice Facilitator/Author) about a similar topic – Root Cause Analysis (RCA), Mike makes a statement I think identifies one of the main barriers to successful OEE implementation today.

Mike: I must admit that a lot of people know of RCA and its implications but very few people use it.  I think it’s because they aren’t able to convince enough of the right people at their work place to try it and then to stick with it.”

In my experience, OEE has had better coverage than the other analysis tools like RCA or Fault Tree Analysis (FTA). This may be due to the fact that Overall Equipment Effectiveness is also a benchmarking tool as well as an analysis tool. In an attempt to grow the numbers who profit from using OEE, I will go over what OEE is, why you should use OEE, and how to use it.

What is OEE?

OEE = Availability X Performance Rate X Quality Rate

AvailabilityPercent of scheduled production (to measure reliability) or calendar hours 24/7/365  (to measure equipment utilization), that equipment is available for production.

Note: measures the percent of time that the equipment can be used (usually total hours of 24-7-365), divided by the equipment uptime (actual production).

Performance RatePercent of parts produced per time frame, of maximum rate OEM rated production speed at. If OEM specification is not available, use best known production rate. 

Note: Performance efficiency is the percentage of available time that the equipment is producing product at its theoretical speed for individual products. It measures speed losses. (e.g., inefficient batching, machine jams)

Quality RatePercent of good sellable parts out of total parts produced per time frame.

Note: Determining the percent of the total output that is good. (i.e. all products including production, engineering, rework and scrap.) 

Example: 50% Availability (0.5) X 70% Performance Rate (0.7) X 20% Quality Reject Rate (results in 80%(0.8) acceptable) = 30%OEE

Why use OEE?

Overall Equipment Effectiveness (OEE) can be used to save companies from making inappropriate purchases, and help them focus on improving the performance of machinery and plant equipment they already own. OEE is used to find the greatest areas of improvement so you start with the area that will provide the greatest return on asset. The OEE formula will show how improvements in changeovers, quality, machine reliability improvements, working through breaks and more, will affect your bottom line.

As you strive towards World Class productivity in your facility, this simple formula will make an excellent benchmarking tool. The derived OEE percentage is easy to understand and displaying this single number where all facility personnel can view it, makes for a great motivational technique. By giving your employees an easy way to see how they are doing in overall equipment utilization, production speed, and quality, they will strive for a higher number!

I highly recommend using an automated equipment monitoring system with an LCD display for your OEE in each respective area of your facility so all can monitor. To the employee in each area, it will become as common to glance at, as the speedometer on a car. While showing machine speed with such a display helps, machine speed is only a small percentage of your overall equipment effectiveness – OEE.

How to use OEE?

Implementing the Overall Equipment Effectiveness formula in your facility can take on many different forms. It can be used as an analysis and benchmarking tool for either reliability, equipment utilization, or both. Don’t let indecision on how to best use OEE become a barrier that prevents you from using it at all. Start out small if necessary, picking your bottleneck to collect the OEE metrics on.

Once you see first hand what a valuable tool it is, you can gradually take OEE measurements on other equipment in your facility. If you work in  manufacturing , there is no substitute for going out to the shop floor and taking some rough measurements of OEE. You will be surprised by what you find!

While monitoring OEE per equipment brings focus on the equipment itself, it may not provide true cause of major costs, unless the cause is obvious. For example OEE can appear improved by actions such as purchasing oversize equipment, providing redundant supporting systems, and increasing the frequency of overhauls.

To improve your OEE percentage, you will need to use other tools and methodologies available to you, like TDC, RCA, FTA etc. TDC is a relatively new methodology that focuses on True Downtime Cost for justification and making better management decisions. You can learn more about TDC at www.downtimecentral.com/tdc.htm. TDC overcomes the main implementation barrier for OEE by giving maintenance managers a tool in which to show actual cost savings in relationship with OEE.

For the ultimate decision making tool, incorporate OEE with TDC.

Front End: Incorporate TDC into your data collection. (contact me for a free power point)

Back End: Incorporate TDC into your software reporting by requiring it of your software vendor.

On a larger scale, you should not only be calculating equipment OEE, you should also be calculating a production line OEE, and within a corporation, a facility OEE. Factory automation companies are starting to incorporate OEE into the reports they generate automatically! There are also a few companies who specialize in providing shop floor data in automatic easy to read OEE reports.

A better reliability solution than RCM

Engineering Driven Reliability (EDR) is the new method for the future of reliability.

Using a plant criticality scoring system (FMEA style) on current machinery is a fine approach for prioritizing equipment importance. A criticality ranking method like FMEA lets you identify what plant is important to your continued operation.

With that knowledge you can decide your asset management strategies. These include your spares holding strategy, preventive maintenance strategy, predictive maintenance strategy and your equipment replacement plans.

FMEA (Failure Mode and Effects Analysis) is one of several methods used for risk assessment and enterprise operational risk management. FMEA also plays a key part in QS 9000. An alternate criticality rating method used in Japan is also discussed in ‘The Pocket Maintenance Advisor‘ available from Feed Forward Publications.

For new equipment I would do a full RCM (Reliability Centered Maintenance). In new equipment you want to get rid of failure risk and operating problems at the component level. RCM will do that for you. It’s the approach to use when you want to design failure-free equipment.

In a way RCM and FMEA are similar. They both focus on reducing business risk from equipment failures. They both deliver a list of design improvements and better operating practices that if implemented to the highest of standards produce greatly improved plant reliability.

The difference is FMEA risk assessment is at the plant equipment level, whereas RCM detects risk at the individual part and subassembly level.

The one major limitation with these techniques is that they do not encourage creative, innovative, new discoveries! They simply promote best practice methods and designs, not break-through, earth-shattering, technological revolutions!

Imagine if Thomas Edison, the inventor of the electric light bulb, had it in his mind to only improve how lighting worked in his day! What if he had approached the task of developing better lighting with an RCM or FMEA mindset? I reckon every night we would now be striking a match to light the longest-lasting, brightest candles in the world!

I hope you can see my point. RCM and FMEA will not break you out of using today’s limiting technologies and designs that we all have to live with (at least until the next ‘Thomas Edison’ comes along). With RCM and FMEA you just end up ‘making a better mouse trap’ and you never discover the new ideas that keep the mice away in the first place.

I hate the limiting technological choices we have to use to build our machines and our businesses! Why can’t we invent new equipment technologies to give outstandingly reliable plant? Other industries have!

Do you realize that from the 1970’s to the 1990’s our entire communication system was revolutionized? We went from sending letters that at best took a week to get a reply, to now sending emails that get replies in minutes.

That is a communications revolution the like of which humanity has ever seen before! That happened over a 20-year period! 20 years … only 20 years … to totally change the way we communicate and make the world better forever!

We need the same thing to happen with the technologies we use in our plant and equipment. We need the equivalent of the 1970’s – 1990’s ‘communications revolution’ in our industrial equipment.

It saddens me to think that roller bearings were invented nearly three hundred years ago when the first clocks were built, and we still use them today. They were definitely a wonderful discovery, and in three hundred years we have got them just about right. But they are not the best solution.

The best solution is a frictionless, lubrication-free, unfailing, unbreakable device. Where is it? Three hundred years is too long to be waiting for the next revolutionary invention in rotating shaft support technology. We must research, innovate, discover, challenge, adventure, excite, explode away from three hundred year-old solutions to our problems!

Thankfully great technological advances are happening with some equipment. The most astounding one I know of is the magnetic shaft coupling (the magdrive pump is another good one).

You can now buy a shaft coupling containing rare earth magnets that lets a motor drive a piece of equipment without having to physically connect the shafts. That is wonderful! No physical contact between parts, only magnetic force fields. That is the sort of equipment engineering revolution I want to see more of!

The magnetic coupling is even more fantastic for equipment maintainers and users, because it does not require perfect alignment. You can be out of line by 6 mm (1/4″), and the motor will still drive the equipment. That means my 11-year old girl can set it up. It doesn’t need a trained technician to get the shafts perfectly in-line with laser shaft alignment equipment. But there is more!

The new technologies I want will do even greater things for us! They will forgive human errors and still operate perfectly. The magnetic shaft coupling is a great example. You can’t destroy the motor or the equipment because the magnetic fields decouple and unlatch the two shafts. So nothing breaks! It needs no maintenance!

You can make ‘human error’ after ‘human error’ and the plant is unaffected! It can’t be broken! That’s marvelous news to every operator and maintainer’s ear. And it makes businessmen jump for joy too! There will be no need to allow for costly maintenance in the budget!

One day we humans will want to fly to Mars and the planets beyond, and come back. But we cannot take a maintenance workshop, a machine shop and a warehouse full of parts to fix our spaceship on the way. We must build equipment that cannot fail. We must have equipment that does not need maintenance. We must have equipment that is fantastically energy efficient. And we must invent them soon!

Yes, it’s good that your company wants to use RCM and FMEA. I encourage everyone to apply RCM and FMEA and RCA and TPM and OEE and the rest. It’s all that we can do at the moment to improve our plant and equipment. And they do work.

Properly implemented they can make a massive improvement to your bottom line results (better to have efficient, failure-free candles than to have to live everyday with candles that keep going out!).

But they will not give you the ‘Thomas Edison type’ industry-changing, world-revolutionizing, humanity-advancing solutions we desperately need to have if we really want to get past our industrial equipment maintenance problems and let humanity fly to the stars!

The problem of technological limitations on equipment reliability (reliability engineering) has absorbed my thoughts and efforts for many months now. I do not believe that we can ever successfully prevent equipment failures by using the methods and technologies available to us today! Even using today’s very best operating methods, designs and training, our technology will let us down in a comparatively short time!

I believe the best approach to rocket reliable equipment is to force technologically innovation to its absolute limits!

Engineering Driven Reliability (EDR) is the new method for the future of reliability. No longer will reliability depend on people doing the right things! Through technological innovation and engineering advancement EDR will insure reliability is built into the machine!

We will have machines and equipment that cannot fail, and remove forever today’s situation where we work to keep the machines going!

Keep an eye on my new web site www.lifetime-reliability.com where you will be able to get designs of outstanding reliability engineering, giving equipment lifetimes more than three and four times normal! You are welcome to become part of a network of engineers, design engineers and technicians motivated to produce new, outstandingly reliable equipment designs.

Best regards,

Mike Sondalini

How a Photo Eye Saved My Job

In 1996 I was employed as maintenance supervisor at an olive cannery in the heart of California’s fertile San Joaquin valley. We were restarting the cannery after an extended shutdown while the cannery changed owners. This was my first opportunity to work in the food industry and a cannery. There were issues for me to learn and learn fast. The new harvest season’s olives were due to start arriving just four weeks after I was hired.

Only four of the previous maintenance personnel were available to be rehired, so things were looking a little bleak at times. None of the new mechanics or electricians had food industry experience, either. In addition, there were almost no blueprints or wiring diagrams for the entire cannery or processing plant.

However, on the scheduled startup day, everything ran. Our two main lines used Angelus 60L Seamers with a maximum output capability of 600 cans per minute. That figures out to ten cans per second. That’s faster than I can count. The Seamers seal the end cap onto the cans. Due to space limitations, new, spiral elevators had been designed and added by the previous owners. The elevators and controls had been wired up but they never ran prior to shutdown.

We started up slow, but problems immediately surfaced. The discharge line from the spiral elevator to the cooker was a plastic cable line. Cans could tip over and jam. When the can jam-up backed cans into the discharge from the spiral elevator and then round and round the elevator. It took a considerable effort and time to remove the jammed cans from the elevator.

A photoelectric sensor with a reflective lens was installed on the discharge cable line about six inches from the can entry to the discharge cable line. This sensor was designed and connected to stop the seamer and elevator when a jam-up occurred. The sensor had to see an opening between the cans, operate on/off, or it would shut down the elevator.

It turned out that the photoelectric sensor could only be adjusted to stay on all the time or off all the time when the cans were going by at any higher rate than Jog speed on the Seamer. We adjusted and adjusted the sensors. The sensors were replaced with new sensors. It did no good. The lines were stopped while we traced all the control and power wiring so we could try to determine if there was a problem in the wiring.

When I looked around, the Plant Manager, accompanied by the company President, Vice President and the Financial Controller were standing to the side watching me. All four of them had their arms crossed and unreadable expressions on their faces. I knew I was in trouble and had to get on top of this problem in a hurry.

Finally, I determined that the previous engineer had ordered an incorrect application for the original photoelectric sensors. I looked up the specifications for the installed sensors and found that their response time was not fast enough to “see” the cans as they went by. I looked in an Allen-Bradley sensor book for a photoelectric sensor with a fast response time, able to withstand the harsh environment of a cannery (steam and water), and would continue operation even when subjected to lots of vibration.

The photoelectric sensor I decided on was the Allen-Bradley Series 4000B Bulletin 42RL. This sensor has a response time of 5 milliseconds. That time was faster than our requirements. The case of the sensor is designed for harsh environments and kept the steam and wash-down water from entering the delicate, control circuitry area of the sensor. The vibrations from the elevator and the cable line had no effect on the solid state wiring of the sensor.

After installation, the sensor was connected and pre-adjusted for the can stream. The sensor kept the cable line and elevator running and was “seeing” the individual cans. We physically simulated a jam-up of cans on the cable line. When the cans backed up to the sensor, the sensor operated and shut down the spiral elevator and opened the clutch on the seamer, stopping line production.

There remained only some fine tuning of the sensor as we ramped up to top speed of between 550 and 570 cans per minute. Again, we had a “command” audience of the top company officers for our startup. When the lines started and continued running or stopped on a can backup with no corresponding elevator jam, there were smiles all around. My job was safe.

Most of the can jams on the cable line were reduced to acceptable levels by the work of the Cookroom Manager and his Seamer Operators/Mechanics. They reworked the can drops and built-in several can cutouts. The can cutouts are places where a can lying on its side will be ejected from the cable line, thereby eliminating an almost certain jam in a can drop or at the Cooker entrance. By reworking the can drops, can jams in the drops were almost totally eliminated.

Besides the fact that I kept my job, I learned that anyone can make a mistake and, when in doubt, check the factory specifications of the equipment you are working with.

About the Author:
Larry Bush has been an electrician for 47 years, and in maintenance management for 22 years.

Industrial Electrical Troubleshooting

Troubleshooting In The Field

Motor Testing

Motor Controller

Programmable Logic Controllers (PLC)

A laptop computer with PLC programming, communication, and operating programs are a necessary tool in today’s modern plant. Engineers, production supervisors, maintenance supervisors, maintenance technicians, electricians, instrument technicians, and maintenance mechanics all need to have PLC and computer knowledge, training and skills in troubleshooting.

On the job training on PLC’s is usually not very effective until the person being trained has reached a certain level of expertise in several areas. Knowledge and skills in electricity, troubleshooting, and computer operation are necessary prerequisites to effectively assimilate basic PLC training. The author found that long term retention of material studied was higher from a vocational course taken at a local junior college than from a fast-paced, cram-course through a manufacturer.

The manufacturer’s course covered essentially the same material as a course at the junior college (JC). The major differences were the amount of study time and shop time. The JC course was four hours of class time per week for 15 weeks. There were three hours of shop time doing actual hands on work of the problems and material covered in the first hour. Additional time was spent at home studying the manual and writing programs. Also, the JC was open at night for extra shop time on the PLC’s and computers.

In contrast, the manufacturer’s course was five, eight hour days. Class work was extremely fast and condensed in order to cover the amount of material involved. The instructor was very knowledgeable and covered the course material as we tried to input the programs into desktop training equipment in order to see how it worked. By the end of each day, our minds were jammed with information. By the end of the week, we all passed the course, but I had a hard time remembering what we had studied on the first day.

Basic troubleshooting techniques apply to every situation and occupation. Positive identification of the problem(s) is absolutely essential to solving the problems. Many times, the inexperienced troubleshooter will mistake one or more of the symptoms for the problems. Solving the symptom(s) will normally just postpone the problems to a later date. By which time, the problems may have grown to mountainous proportions.

An example is when a person experiences a headache and takes a mild pain reliever, such as aspirin. The actual problem might be any number of things: eyes need to be checked, medication or lack of medication, muscle strain, stress, tumor, blood vessel blockage, or old war injury. The same thing occurs in industry, a fuse in a circuit blows and the maintenance person gets the replacement fuse and inserts it into the fuse holder. There are many things that could have caused the fuse to blow, depending on the complexity of the circuit.

Excess current caused the fuse to open (blow). Excess current could have been caused by: overload on the load; short circuit between the wires, grounded wires, short circuit in the load, ground in the load, voltage spike, voltage droop, etc. If the maintenance person does not troubleshoot the circuit prior to replacing the fuse and restoring power, negative consequences could arise.

It is not uncommon for a process to develop a number of small problems and continue to function at a degraded level of operational capability. Then, one more small problem occurs and the whole process breaks down. Finding and correcting the last problem will not necessarily restore the operational capability of the process. The process continued operations with the small problems, but the small problems may not allow the process to restart from a dead stop. All the other small problems must be identified and corrected before the process is restored to full operational capability.

This situation arises in industry as well as a person. The person can continue to function with a number of small problems, such as fatigue, blood pressure problems, hardening of the arteries, artery blockage, but one more small blood clot in the wrong place could easily cause the death of the person. Clearing the blood clot does no good to the person. They will not be restored to full operational capability.

Troubleshooting In The Field:

Unless prior experience dictates otherwise, always begin at the beginning.

Ask questions of the Operator of the faulty equipment:

* Was equipment running when problem occurred?

* Does the Operator know what caused the problem, and if so, what, in their opinion, caused the problem?

* Is the equipment out of sequence?

* check to ensure there is power

* turn on circuit breaker, ensure motor disconnect switch is on, and operate start button/switch

Use voltmeter to check the following at incoming and load side of circuit breaker(s) and/or fuses, ensure that voltages are normal on all legs and read voltage to ground from each leg:

* main power, usually 460 VAC between phases and 272 to ground

* control & power, 208/240 between phases and 120 to ground and 120 VAC to neutral on a grounded system

* low voltage control power, usually 24 to 30 VAC and/or VDC between phases and possibly to ground, usually negative is connected to ground

Check controlling sensors in area of problem, then make complete check of all sensors, limit switches and other switches to ensure they are in correct position, have power, are programmed, set, and are functioning correctly.

If and when a problem is found, whether electrical or mechanical, the problem should be corrected and the fault-finding begun anew, a seemingly unrelated fault or defect could be the cause of the problem.

When there is more than one fault, the troubleshooting is exponentially more difficult, do not assume that all problems are solved after completing one, always test the circuit and operation prior to returning the equipment to service.

If available, check wiring diagrams and PLC programs to isolate problem.

Variable Frequency Drive (VFD) can be reset by turning power off, wait till screen is blank and restore power; on some VFD’s, press Stop/Reset – then press Start.

Check that wiring is complete and that wires and connections are tight with no copper strands crossing from one terminal to another or to ground.

Ensure that the neutral reading is good and that the neutral is complete and not open.

Motor Testing In Shop:

Prior to connecting a motor:
* move motor to electric shop motor test and repair station

* connect motor leads for 460 volt operation and wrap connections with black electrical tape

* check motor windings with an ohmmeter, each reading between phases should be within one or two ohms of each other; A to B, B to C, A to C

* use megohmmeter to check insulation resistance to ground of motor windings on 500 volt scale; minimum reading is 1000 ohms of resistance per volt of incoming power that motor will be connected to

* connect motor to power test leads and safety ground after checking that test lead power is shut off; secure motor to table to prevent motor from jumping when started; turn disconnect on; press start button; check “T” leads for motor amperage; check for abnormal sounds and heat in bearings or windings; clean motor shaft; shut down and disconnect

Motor Testing In Field:

When a motor overload or circuit breaker trips and/or blows fuses, certain procedures and tests should be carried out:

* lockout and tagout main circuit breaker;

* test insulation resistance of motor wires and windings by using megohmmeter between T1, T2, & T3 leads and ground, then;

* test “T” leads to motor with ohmmeter for continuity and ohmage of windings between A to B, B to C, A to C; each resistance should be within 1 or 2 ohms of each other; if the ohms readings are significantly different, or, if there is no continuity; go to the motor disconnect box, turn it off, perform the continuity and resistance test on the “T” leads, again; if the readings are good, the problem is in the wires from the motor controller to the disconnect switch;

* check the three wires by disconnecting all three wires from switch and twist together; go to controller and check for continuity between A to C, B to C, A to C; one or more wires will be open or grounded;

* correct solution is to pull all new wires in from controller to motor disconnect switch, whatever caused the problem may have damaged the other wires, also, replace all wires

* if problem is on motor side of disconnect switch, open motor connection box and disconnect motor;

* check motor for resistance to ground with megohmmeter, if reading is below 500,000 ohms, motor is grounded and must be replaced;

* test motor windings for ohms between phases with ohmmeter A to B, B to C, A to C, readings should be within 1 or 2 ohms of each other; if readings indicate open or a significant ohmage difference, replace motor;

* if motor test readings are good, test the motor leads between the disconnect switch and the motor connection box for continuity and ground resistance, if readings are not good, replace wires;

* if all readings are OK, reconnect motor, remove lockout, and restore to service; the problem could have been mechanical in nature; an overload on motor caused by the chain, belt, bad bearings, faulty gearbox, or power glitch.

Motor Controller:

* check motor Full Load Amps (FLA) at motor and check setting on controller overload (OL) device; most newer OL devices are adjustable between certain ranges, some older OL devices use heaters for a given amperage

* if circuit disconnecting means in controller is a circuit breaker, it should be sized correctly

* if the disconnecting means is a Motor Circuit Protector (MCP), the MCP must be correctly sized for the motor it is protecting and the MCP has a trip setting unit which has to be correctly set based on the Full Load Amperage of the motor; using a small screwdriver, push in on the screw head of the device and move to a multiple of thirteen of the FLA; example: a motor FLA of 10 amps would require that the MCP trip device be set to an instantaneous trip point of 130 amps

* fuses protecting the motor should be the dual element or current limiting type and based on the motor FLA

Programmable Logic Controllers (PLC):

* check to ensure main power is on( 120 VAC

* check 24V power available

* identify problem area

* check sensor operation in problem area

* check sensor Inputs to PLC

* check on PLC that a change in sensor state causes the corresponding Input LED on the PLC to go on or off

* identify Output controlled by Input on PLC ladder diagram

* ensure that Output LED is cycling on/off with Input

* check that Output voltage is correct and cycling on/off with Input

* locate Output device and ensure that voltage is reaching device and cycling with Input

* ensure that Output device is working correctly (solenoid coil, relay coil, contactor coil, etc.)

* an Input or Output module can be defective in one area or circuit and work correctly in all other circuits

* if each field circuit is not fuse protected, the modular internal circuit becomes a fuse and can be destroyed by a field short circuit or any other over-current condition

* check modular circuit; if bad, module must be replaced after correcting field fault

* shut down PLC prior to changing any module -main power and 24V power

* locate fault in field circuit by disconnecting wires at module and field device, check between wires for short circuit and to ground for short circuit; replace wire is short circuit found

* check device for ground, short circuit, mechanical and electrical operation, even when problem found in wires, always also check device for another fault, problem in wires can cause problem in device or vice versa; if device defective, replace device and then check total circuit before placing in operation and after restoring circuit, check again to ensure circuit and module are operating correctly

* check power supply module; if no output, shut down power and replace supply module

* back plane can go bad, some of the modules with power and others with no power, replace backplane

* sometimes, the PLC can be reset using the Reset key switch; ensure that turning the PLC off won’t interrupt other running sub-set programs, turn keys witch to far right, after 15 seconds, turn to far left wait, then return to middle position; this operation should reset program and enable a restart

* the PLC program can have a latch relay with no reset under certain conditions, the key switch reset may have no affect on the latch, try turning the power to the PLC off and back on, this operation may reset the latch and allow the program to be restarted

* the PLC is usually part of a control circuit supplied with 120VAC through a 460V/120V transformer as part of a system with motors, controllers, safety circuits, and other controls; occasionally, cycling the main 480V power off/on will be necessary to try to reset all the safety and control circuits

* possession and use of an up-to-date ladder diagram, elementary wiring diagram, manufacturer’s manuals & diagrams, troubleshooting skills, operator’s knowledge, and time are all required to solve issues involved in maintaining a modern manufacturing production line.

 

About the Author:Larry Bush has been an electrician for 47 years, and in maintenance management for 22 years.

Using RCM Turbo Preventive Maintenance Software

We have now looked at the how to lay out the PM, the next thing to concentrate on is the “when” should this PM be done? Most PM’s get initiated in a ritualistic manner. Some form of active god has caused a problem, and we are now going to put a PM in place to insure it never happens again. This now becomes tribal lore and when asked 10 years later, “Why do we inspect that elevator once a week though we never find anything wrong?” The response is always the same, “Because.”

You should only want to do the work that you need to do when you need to do it. The most effective way to do this is by using RCM tools such as FAILURE MODES AND EFFECTS ANALYSIS. The only problem with this is that it can take you years and lots of time to complete just one PM. We found a new tool that can streamline this process down to minutes. It can be accomplished by anyone even an apprentice. This software is called RCM Turbo and it takes you through the FMEA Process in a logical order quickly and efficiently. It starts with doing a critical analysis of the process unit (see Fig. 1).

preventive-maintenance-software

Fig.1

Once you have accomplished this and have looked at all the possible primary failures, it allows you to go down to the maintainable equipment level (see Fig. 2).reliability-centered-maintenance

Fig. 2

By following a series of questions it will tell you what type of PM should be carried out. This would include FTM or “fixed time maintenance” CBM or “conditioned-based monitoring” or RTF “run to failure” (see Fig. 3).

fmeamtbfFig.3

The last thing that RCM Turbo allows you to do is a reliability risk assessment. It will actually chart what you need in time and cost for 100% reliability but if 98% reliability is good enough it will tell you what the new time frame will be. This allows you to set your PM’s to the correct frequency and risk to be the most effective for your facility quickly and easily (see Fig. 4).

reliability-predictionFig.4

maintenance-preventive-schedule

The other aspect of this tool is it allows you to build a library of associated equipment, so that you do not have to repeat the FMEA Process on each one. We have found that by having the correct task sheets and the right frequencies, PM’s become more efficient and people become more attuned to the whole concept of Preventive Maintenance. When your PM’s are run through RCM Turbo you will find you are now focusing on things that you never thought of and that you have much more time to do corrective maintenance work. Our studies have shown that most companies tend to over PM when they do PM and to not PM the correct equipment. We know that there is not a perfect PM but it is a working document that RCM Turbo can quickly and efficiently help write.

 

2. Click for Example Preventive Maintenance Template form.

1. Back to developing a Preventive Maintenance Program (PM)

Preventive Maintenance

Task Example:

9 – MONTH PM FOR PLANT AIR COMPRESSOR # 2 (SULLAIR)
______________________________________________________________
ALWAYS WORK SAFE, FOLLOW ALL SAFETY PRECAUTIONS
______________________________________________________________
PERFORM THE FOLLOWING TASK
______________________________________________________________
STARTING STEPS:

_____ 1. NOTIFY PRODUCTION THAT MAINTENANCE TASKS ARE BEING PERFORMED

_____ 2. INSPECT WORK AREA FOR SAFETY AND CLEANLINESS

_____ 3. INSTALL LOCKOUT/TAGOUT IN ACCORDANCE WITH COMPANY PROCEDURES

_____ 4. INITATE PERMIT SPACE ENTRY PROCEDURES IN ACCORDANCE WITH COMPANY PROCEDURES.

TASK:
_____ 1. REMOVE ALL PRESSURE FROM THE SUMP TANK AND PACKAGE PIPEWORK.

_____ 2. DISCONNECT ALL PIPEWORK CONNECTED TO THE SUMP COVER.

_____ 3. LOOSEN AND REMOVE THE TWELVE (12) HEX HEAD CAP SCREWS FROM THE
COVER PLATE. LIFT THE COVER PLATE FROM THE SUMP.

_____ 4. REMOVE THE TWO (2) NESTED SEPERATOR ELEMENTS.

_____ 5. SCRAPE THE OLD GASKET MATERIAL FROM THE COVER AND SUMP FLANGE –
AVOID DROPPING ANY SCRAPS INTO THE SUMP.

_____ 6. INSPECT THE SUMP VESSEL FOR RUST, DIRT, ETC. REINSERT THE SEPERATOR
ELEMENT, PART # 02250060-462 (PRIMARY) 02250060-463 (SECONDARY)
WITH GASKET ATTACHED, INTO THE SUMP, TAKING CARE NOT TO
DENT THE SEPERATOR ELEMENT AGAINST THE TANK OPENING.

_____ 7. REPLACE THE COVER PLATE AND RE-FASTEN WASHER/CAPSCREW
ASSEMBLIES TO 155 FT. – LBS.

_____ 8. RE-CONNECT ALL PIPEWORK, MAKING SURE THE RETURN LINES EXTEND
WITHIN ¼” FROM THE BOTTOM OF EACH ELEMENT. THIS WILL ENSURE PROPER
FLUID RETURN DURING OPERATION.

_____ 9. CLEAN THE RETURN LINE STRAINERS.

WARNING: DO NOT REMOVE GROUNDING STAPLES FROM THE GASKETS. DO NOT USE ANY TYPE OF GASKET
ELIMINATOR. DOING SO WILL INTERFERE WITH GROUNDING CIRCUIT AND MAY CAUSE SEVERE SHOCK.

NOTE: THIS PM IS TO BE COMPLETED AT LEAST EVERY 9 MONTHS OR AS INDICATED BY THE MAINTENANCE
GAUGE.

CLOSING STEPS:

_____ 1. REMOVE LOCKOUT/TAGOUT AND RETURN EQUIPMENT TO NORMAL OPERATNG CONDITION.

_____ 2. NOTIFY PRODUCTION THAT MAINTENANCE TASK ARE COMPLETED AND EQUIPMENT IS
AVAILABLE FOR PRODUCTION.

_____ 3. CLEAN-UP WORK AREA AND INSPECT FOR SAFETY CONDITIONS.

_____ 4. INITIATE WORK REQUEST TO CORRECT NOTED DEFICIENCIES OR UNACCEPTABLE
CONDITIONS.

_____________________________________________________________
NOTE: ANY EXCESSIVE DAMAGE OR WEAR FOUND WHILE PERFORMING THIS TASK IS TO BE REPORTED IN THE
COMMENTS SECTION OF THIS WORK ORDER AND TO YOUR SUPERVISOR.
______________________________________________________________

COMMENTS:__________________________________________________

I have completed this work as laid out._________________________________

 

1. Back to developing a Preventive Maintenance Program (PM)

3. On to Preventive Maintenance Software

Writing the Perfect PM

Preventive Maintenance (PM) training and software article by Ralph Hackle

How many times have you walked into a plant and asked to see the PM program and were told that it was not documented. Maybe it was documented and you read things like “check meter” or “inspect a belt”. What were you suppose to be checking for? My two personal favorites are “ We have Clem and Joe doing our PM’s”. “ We don’t know exactly what they do but they sure do a lot of it”. The next one is the daily PM that has to be dome Monday thru Friday but for some reason not on Saturday or Sunday or when Clem is on vacation. If some of these statements hit home for you, then you need to know how to write the perfect PM.

The first step to developing the perfect PM is to develop a template. This template should be built on a logical sequential order. It must be worded clearly and concisely and it should contain these points and probably more.

  • A contact person for the area of work. Communications are essential.
  • Each step needs to have some form of a check off such as a __________ or o.
  • Safety consideration well documented such as “lock out/ tag out” procedures or equipment specific safety precautions.
  • A listed of all needed parts and special tools.
  • When using the word check or inspect, be clear as to what needs to be looked at and if needed what to do when found.
  • Example: Inspect shaft for signs of wear such as cracks or discoloration. If found note on inspection sheet.
  • Example: Check meter. Meter should read between 25-40. If out of range either way note on check sheet and immediately inform shift supervisor.
  • Task sheets need to be written for the specific skill level doing the work.
  • Task sheets need to be written as if employees are new to the facility.
  • Task should have a specific crew size and hours.
  • When working on multiple levels or equipment, a flow to the work should be laid out.
  • If certain specifications are always needed when performing the task, they need to be included.
  • If OEM manuals or prints may be needed for reference, always give their locations and keeper.
  • A sign off at the bottom of the task sheet that shows it was completed should be included.
  • Periodically, give out a task planning survey sheet when doing the task. This feedback will be invaluable to the planner and gives the workman say in design.

Click for Example Preventive Maintenance Template form.

On to Preventive Maintenance Software

Preventive maintenance of plant plc controller automation

Maintenance of your Plant Automation:

PLC (Programmable Logic Controller)

What is a PLC?

  • How many PLC controllers is your bottom line depending on?
  • Do you have an up to date list of all PLC controller model types, part availability, program copies, and details for your plant?
  • Do you have at least one trained person per shift, to maintain and troubleshoot your plant automation and PLC controllers?
  • Does your plant maintenance personnel work with PLC controllers following written company or corporate policy, and procedures?

If you could not answer with confidence or you answered ‘No’ to any of the above questions, you need to read this article on maintenance of plant automation and PLC controllers. Why? Because the PLCs (Programmable Logic Controllers) are the brains of your operation. When the PLC controller is not functioning properly, lines shut down, plants shutdown, even city bridges and water stations could cease to operate. Thousands to millions could be lost by one little PLC controller in an electrical panel that you never even knew existed. But most importantly, damage to machine and personnel could result from improper plant wide maintenance of your company’s PLC controllers.

What is a PLC?

First I’d like to explain in the most non-technical terms possible, What type of automation a PLC controller is. As this article is not just for the maintenance technician, but for maintenance managers, plant managers and corporate managers. A PLC (Programmable Logic Controller) is the type of computer that controls most machines today. The PLC is used to control AND to troubleshoot the machine. The PLC is the brain of the machine. Without it, the machine is dead. The maintenance technicians we train, are the brain surgeons. That is how I explain it to my doctor any way. (His mouth drops open, “… you train brain surgeons?”)

Important Note: Just as a doctor asks the patient questions to figure out what is wrong, a maintenance technician asks the PLC questions to troubleshoot the machine. The maintenance technician uses a laptop computer to see what conditions have to be met in order for the PLC to cause an action to occur (like turn a motor on). In a reliable plant maintenance management environment, the maintenance technician will be using the PLC as a troubleshooting tool to reduce downtime.

A little more detailed definition of a PLC controller: A programmable controller is a small industrial strength computer used to control real world actions, based on its program and real world sensors. The PLC replaces thousands of relays that were in older electrical panels, and allows the maintenance technician to change the way a machine works without having to do any wiring. The program is typically in ladder logic, which is similar to the wiring schematics maintenance electricians are already accustomed to working with. Inputs to a PLC can be switches, sensors, bar codes, machine operator data, etc. Outputs from the PLC can be motors, air solenoids, indicator lights, etc.

How many PLCs is your bottom line depending on?

My company has had an ongoing PLC related global maintenance survey since the year 2000. The majority of the participants back in 2001, reported 3-6 PLCs in their facility, that they know of. Granted most participants are managers and don’t open electrical panels much, but many of the participants are from fortune 500 companies having hundreds of employees. The odds are most of them have 12-30 PLCs in their facilities. Currently the average is 6-9 reported, so the good news is the industry as a whole is becoming more PLC aware.

It is common to only learn about a PLC once the machine is down and the clock is ticking at a thousand dollars an hour, or more. Unfortunately, it is also common that after the fire is out, it’s on to the next fire, without fully learning what can be done to avoid these costly downtimes in the future, and in other similar machines in a company or corporation.

Some older electrical panels may only have relays in them, but most machines are controlled by a PLC. A bottleneck machine in your facility may have a PLC. Most plant air compressors have a PLC. How much would it cost if the bottleneck or plant air shut down a line, a section of your facility, or even the entire plant?

Do you have an up to date list of all PLC model types, part availability, program copies and details for your company?

The first step to take is to perform a PLC audit. Open every electrical panel, and write down the PLC brand, model, and other pertinent information. Then go the next two steps. Analyze the audit information and risk, then act on that analysis. To help you out, I want to share with you our company PLC audit form.

Collected Information Recommended Action
Machine or Area Name Ex: warehouse conveyor, pump station 3, Strapper 2, Line 7, Traffic signal west main, etc.
PLC Program Name Ex: 1789GAA1, P3, Strap2, 5872443, WestMainTL, etc.
Network Node Address No two addresses will be the same. Ex: 2, 3, 17, 21
Network Name Common to be same as Program name, but not mandatory.
PLC Brand Ex: Allen Bradley, Siemens, Schneider, Mitsubishi, DirectSoft, Omron
PLC Model Number Ex: PLC-5/25, SLC-504, SIMATIC S5, MELSEC FX1N, DL 405
Is Spare Available Yes on shelf, or only in less critical machines or no
Date Program Last Backed Up Make program backups part of your semiannual PM program
Discriptored Copy of program available Without discriptored copy of program, troubleshooting and downtime are greatly increased.
Does PLC have EEPROM Or other method of storing backup program in a chip on PLC
Last date Program Changed Remember to log when outside consultants or OEM make program changes too.
Last date EEPROM Burned Should be saved to EEPROM (Burned) after every successful program change.
Date battery last changed See manufacturer’s data for recommended change frequency.
Other information you may need Might be facility location when corporate HQ is using this form.

Other information you may need Might be facility location when corporate HQ is using this form.
Once you have collected the basic information in your Plant wide and/or corporate audit, you need to analyze the information to develop an action plan based on risk analysis. In the risk analysis, bottlenecks and other factors will help you assess priorities. Starting with the highest priority PLC, you will need to ask more important questions.

  • Do we have the most common spares for the PLC?
  • Is the OEM (Original Equipment Manufacturer) available 24/7? Or even in business any more?
  • Do we have a back up copy of the PLC program?
  • Does our program copy have descriptions so we can work with it reliably and efficiently?
  • o Do we have the software needed to view the PLC program? Are our maintenance personnel trained on that PLC brand?

These are some of the questions our managers must ask, to avoid unnecessary risk and to insure reliability.

Do you have at least one trained person per shift to maintain and troubleshoot your plant PLCs?

Is your maintenance staff trained on the PLC? (Silly to squander over a couple thousand in maintenance training when the lack of PLC knowledge could cost you 10 thousand an hour. … or worse. I can give you a couple good reasons why you should have at least one trained person per shift, to work reliably with PLCs. You do not want to see greater downtime on off shifts because the knowledge base is on day shift only. Also with all the baby boomers (our core knowledge base in the industry) about to retire, it is not smart management to place all your eggs in one basket.

Then the question should be asked, what should we look for in training. Well I have been training individuals for over a decade and could easily write another article on just PLC training alone. I can tell you here, that you should seek training with two primary objectives.

The training you decide on, should stress working with PLCs in a Safe and Reliable way. (not just textbook knowledge or self learned knowledge)
Secondly, the training should be actually centered around the PLC products you are using or plan to use in your facility.
I feel the two criteria above are the most important. Some other good ideas to get more out of your PLC training investment would be to get hands on training using the actual PLC programs and software the maintenance technician will be working with in the facility. Insure your personnel have the software, equipment and encouragement to continue with self education. PLC Training CBT (Computer Based Training) CDs are a great way for employees to follow up 6 months after the initial training. Some other ideas you could do is to provide them with simulation software and/or a spare PLC off the shelf to practice with.

Does your maintenance personnel work with PLCs following written company or corporate policy and procedures?

It seems that in our industrial culture, if policy and procedures are not written and enforced, we eventually stray back to the old unreliable ways. I have reviewed many policy and procedures as well as books on the topic matter and hardly ever see maintenance management of the PLCs included. It amazes me how an organization can write guidelines for what they believe is the health of the entire organization’s body, and leave out the brain (the PLC :>). Once again, a complete PLC policy and procedure manual is out of the scope of this article. However, I will donate a few random items below to get you started.

  1. Write PLC policies and procedures into your existing maintenance policy and procedures. (SOP)
  2. All personnel working with PLCs will be trained on that PLC equipment.
  3. Backup copies of the PLC programs will be made every 6 months regardless of change status.
  4. If a PLC program has been changed …
  5. It will be documented in the software copy, in the printed copy and in the CMMS program.
  6. Copies of the PLC program will be stored on a media more reliable than floppy disk (CD, USB, etc.).
  7. Multiple copies will be stored on laptop, maintenance manager’s office and off site (corporate).
  8. If available, EEPROM will be updated with new changed program.
  9. If outside vendor changes, a-d will be performed by maintenance personnel
  10. Future equipment purchases …
  11. A common PLC brand in all equipment will be sought out (Standardization of PLC types)
  12. OEM will be required to provide a descriptor copy of PLC programs in the customer’s native language.
  13. All PLC 110v control voltage will have a line filter on it.
  14. All PLCs will have the backup EEPROM option for zero downtime in some failure modes.
  15. Forcing inputs and outputs on or off shall be treated as a Safety issue. (See safety SOP)
  16. Inputs and outputs shall not be forced on or off with out a clear understanding of complete effect on PLC program and a second opinion.
  17. If forces are installed, they shall be removed with in 24 hours and a more permanent solution found.
  18. All forces should be documented in software and a written log before being enabled.
  19. Online programming is somewhat of a safety risk, normal procedure is to change offline and download to the PLC.

Hope this helps, if you have a specific question you can find me in our PLC discussion area at the PLC Discussion Forum. – Don Fitchett (President)

Business Industrial Network

PLC Training – The best for less

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