If there are machines in place, then there will be breakdowns
Published by : Industrial Automation
Shacheendra Bapat, Automotive and Manufacturing Industry Professional.
Maintenance is a critical aspect of industry – how do companies decide their maintenance strategies?
Being considered as a non-productive function, most of the companies do not have a proper strategy in place for Maintenance. They may not even consider having a strategy for maintenance in the first place. Some companies do have a strategy in place. It starts with having adequate maintenance manpower with required skill set. A good leader at the top, followed by leaders at department locations and then the working Technicians (mechanical and electrical) on the machines is the most important dimension of Maintenance strategy. The strategy should be in place at the time of erection of the plant. It should include the training plan, budget for spares, maintainability of the equipment at the design stage (adequate space in the electrical cabinet and around the equipment, free input and output channels in the PLC, common components in multiple machines), pre-planned location of Maintenance area on the shop-floor with all the required facilities (work bench, three phase and single phase power supply, compressed air supply, 24 volt DC Power supply, consumable spares storage, space for keeping adequate and correct documentation, portable welding machine), a simple yet useful Maintenance Management Software, availability of all Critical tools and a helpful hand on the back of the Maintenance team. While the PFMEA is in place in several organisations, the Equipment FMEA is not. It should be a part of the Maintenance Strategy.
Many companies have their own Manufacturing Systems like TPS or BPS. Integration of the Quality Management System (QMS) and Environment Management System (EMS) in the Manufacturing System for Maintenance function must also be part of the Strategy.
Why do companies still rely on corrective maintenance despite other options?
The companies do not want to spend money on the maintenance function. This is because, it is very difficult to quantify the benefits on the money spent. For example, if the downtime is reduced, then the productivity increases. However, the time for which the machine availability is increased, cannot be justified in terms of money, as the electricity or manpower saved is difficult to quantify. Having a correct instrument like a Multi-meter may greatly reduce the Mean Time To Repair (MTTR). However, the money spent on the Multi-meter cannot be quantified vis-a-vis the reduced MTTR. If a maintenance person proposes certain improvement, the question he hears is “The machine is running, no? Then why do you want to spend the money?” This bmanagement attitude discourages the maintenance person and the age old concept of corrective maintenance continues. The middle managements do not have guts to demand money from the top management for carrying out improvements.
Has predictive maintenance become easier to implement in the IIoT era?
Not really. Predictive Maintenance through IoT will be successful only and only if we have appropriate sensors in place, which will provide a decipherable data. For example, I have a big Hydraulic Power pack installed on my machine. To initiate a Predictive Maintenance on this power pack, I require following things:
1. A good vibration sensor, which will give the front and rear end motor bearing data.
2. A good vibration sensor, which will detect abnormal noise in the pump.
3. A good temperature sensor, which will give real time data of motor temperature.
4. A good sensor, which will give real time viscosity status of the hydraulic oil.
5. A good sensor, which will give real time in-line filter condition.
Not only that these sensor should withstand the ambient conditions, they should be easily mountable on the components as well. And this is just for the power pack. If one talks of other parts like, coolant system, spindle, moving axes, etc., then mounting the sensors on them becomes more critical. I am yet to come across a sensor that will give me the correct condition of a guide-way bearing. Further, this will only add to the maintenance of these sensors themselves in the existing list of to do items.
How important is inventory management for a successful maintenance strategy?
The Spare parts Inventory Management is extremely important aspect of Maintenance. It requires a lot of foresight and experience. Lack of critical spares may jeopardise production and unnecessary stocking may lock revenue and space. The managements should leave the decision on the purchase of spares to the maintenance managers. What best can be done is to fix a budget depending upon the financial condition of the company. The Maintenance manager can identify which part is needed the most. Usability of a part in multiple machines, lead time of procurement, shelf life, in-house reparability and frequency of failure are some of the key deciding factors.
With emerging technologies like AI & ML now coming into play, is Zero Downtime now with sight?
Let us agree on one thing. If there are machines in place, then there will be breakdowns. With excellent research and development done in the field of aviation sector in the last 100 years, aircraft accidents still happen. Any management (rightly so) expects improvement in Mean Time Between Failures (MTBF). However, the first step to achieve this is by reducing the Mean Time To Repair (MTTR). The reduction in MTTR itself significantly improves the Equipment Up- Time. Having AI and ML cannot eliminate the need of Preventive Maintenance, which is the core of having less or zero breakdowns. It so happens many times that Preventive Maintenance itself causes subsequent breakdowns, if incorrectly executed. So howsoever excellent AI and ML could be, the executioners are still human beings. Effective training, adequate manpower and correct planning can greatly reduce the breakdown time after performing Preventive Maintenance The concept of Reliability Centred Maintenance was brought in the early 1970s in the aviation sector jointly by Boeing and the United Airlines and it worked wonders. It was later adopted
successfully by the Process Industry. We are lucky that respected John Maubrey brought it to manufacturing industry. However, the success of RCM, like TPM, entirely depends upon the participation of the management and the Production department in the RCP Process implementation and Execution. If implemented correctly, we can reach to the dream of zero breakdown.
As the world battles the Covid-19 pandemic, will maintenance call for altogether different strategies?
It will definitely call for some changes in the strategy in the Process Industry. The industries running for 24 hours and 365 days a year, may severely face the shortage of skilled manpower, availability of spares parts at the right time and unavailability of requisite vendors due to long shut down periods. The manufacturing industry may not get hit that hard. I work in the manufacturing sector. We just kept the Electric Power of all our machines in On condition. During the lockdown period, I with my colleague visited our plant twice. We ran our Diesel Generator, Compressor and the Fire pumps for some time, operated our Robotic equipment to get the axes moved and ran the chillers. When we started our production after a gap of 48 days, we did not face a single start up related breakdown. Keeping the Electric power On was the key to achieve tShacheendra Bapat, graduate in Electronics and Telecommunication engineering, is an Automotive and Manufacturing Industry professional having more than 26 years of experience in operation and Maintenance of Flexible Manufacturing System, HMCs, VMCs, SPMs, welding machines, paint shop equipment and conveyors. A Technical Trainer for Industrial Automation, Electrical Safe Work Practices, Maintenance Safety, Chemical Safety, Predictive and Preventive Maintenance, etc., Shacheendra is also a Certified Lead Auditor for QMS ISO 9001:2008, Certified Internal Auditor for EMS ISO 14001:2004 and Certified Project Management Associate IPMA Level D. He has worked with Hindustan Motors Ltd, Eicher Motors Ltd, General Motors Ltd and Bosch Rexroth India Ltd.his.