Plant / Process Maintenance

[mnt]

Quick question for any Process Engineers involved with Maintenance issues - Does Maintenance Engineering OR Operations dictate the frequency of preventive maintenance? Thanks.

 

[quark]

Seems you had a fight with maintenance, huh. Keeping aside personal feelings, the work should be done collectively. Anyhow my first preference is to process (if the issue is not very critical)

I strongly feel that nobody should dictate.

Best regards,

 

[JOM]

mnt,

>Does Maintenance Engineering OR Operations dictate the >frequency of preventive maintenance? Thanks.

Great question. My view is that Operations "own" the plant, and Maintenance provide a service. Operations should define an expected service level and Maintenance should meet that.

The particulars of preventative maintenance on individual items of plant may very well be up to Maintenance, but they should deliver the performance expected by Operations.

This issue becomes far more serious when safety is involved. It has been known for Maintenance to address process upsets as a maintenance problem, when it has safety implications, and the lives of Operations personnel are at risk.



Cheers,
John.

 

[mnt]

Thanks guys.
No fight .. just a difference of opinion!
Personally, I feel that PM should be planned on a frequency basis. Operations 'should' be able to schedule this 'down-time' into production??
- safety pending of course!

 

[Fritzfrederix]

Hi there,

At our plant we did preventive maintenance for several years. All the time the maintenance people defined the frequency because we had all the results of the preventive maintenance. When it came to shedule the preventive maintenance it was done together with operations.
Nowadays we meanly do predictive maintenance, it a more accurate way to do maintenance. It's much cheaper and we've got alot less downtime caused by the preventive maintenance. You need to have historical data to do so.

Rudi Frederix

 

[longeron]

Production owns the plant and maintenance provides a service. That is a widely held point of view.

I think that the larger question is who owns the entire plant? The company does. The company that employs both the operators and the machinists can shut and padlock the gates not operations, not maintenance. The company is contracting operation of the plant to one group of employees and maintenance of the equipment to another. If the profit margin is not great enough for long enough operations doesn’t decide to just quit and walk away, the company decides to lay everyone off and auction off the equipment.

In my utopian point of view operations and maintenance have a duty to work together in order to provide the company with reliable production of a widget or polyethylmethynastylatin at a decent profit margin.

To do this maintenance cannot break into the production schedule too often, but must be allowed access to equipment before it’s condition becomes dangerous or to is too degraded to make it worthwhile to repair. Operations also has a responsibility to operate the equipment properly (I know my colors show here, too many times I’ve seen pumps beaten with hammers and wrenches or started improperly) and needs to be able to meet or beat customer delivery dates.

I’ve thought that the best way to achieve a balance of power here is to ensure that everyone has a view of the big picture and understands what the other side believes is important. The big picture is the company perspective. This can be explained during orientation training of new operators and machinists. Explaining the point of view of an operator to a machinist is difficult, and so is explaining a machinist’s viewpoint to an operator. So why not have a junior machinist and operator swap for six months? What better way to help spread the gospel that the plant is one big happy family? What better way to show that the grass is just as brown on the other side of the fence? I believe that after a few of these swaps in each unit that operator induced machine failures would dramatically decrease as would infant machine start-up failures due to improper maintenance.

Machinists would understand the subtleties of operating the equipment and what conditions cause failures, they would understand the frustration of watching multiple equipment failures while trying to meet a production schedule. Machinists would see how awkward it is to start one pump when the discharge valve chain fall is so far away. Operators would learn how the operation of a piece of equipment effects its’ performance. Operators would learn how frustrating it is to work on the same thing time and time again because of a process condition.

The more people know about the effects of their actions on others the more careful they will become. This could eliminate the counterproductive us against them attitude that is pervasive in so many plants. With this greater understanding process up time would increase as maintenance issues decrease.

 

[JOM]

longeron,

You've covered a lot of ground there and made many sensible points.

I studied a bad accident at a petrochemical plant and saw that while both operations and maintenance do great work, problems still occurred regarding unserviceable plant and ad hoc operational make-do approaches in response to failed equipment.

As you say, the real owners are the corporation, represented by the management. And where are they? On-site or at Corporate HQ? Who suffers when plant explodes?

After looking at this case, my thoughts were that the plant needed an individual whose duties were to ensure plant was healthy. Not for operational needs, or maintenance economy, but just from an outright determination to protect his plant from damage, misuse and deterioration. A real jealous sort who gets angry when his equipment is maltreated. I think such a person would be a process engineer.

Don't know if this is a new idea, but does it make any sense?

Cheers,
John.

 

[Samiran]

All,

I always try to give an example of pumps seal failure in these kind of situations. Yes Process Engineers do care about the seals but only from an outside sense. When it comes to replacement with a different type usually PEs back out and let the experts take the lead.

What is the cost of preventive maintenance ? It is not zero and neither it can be allowed to be zero. As JOM indicates who suffers when the seal explodes - it is the operators. But there is a way of determining the critical equipment and focussing on those rather than do a blanket PM. Risk Based Inspection (RBI) is the latest tool for this.

Reliability Engineers along with PEs should first determine the critical equipment in the asset and then look for the failure history and the impact they have caused or may have caused. Based on that frequency need to be developed and this will vary from site to site and from equipment to equipment depending on the type , criticality and material quality employed.

Who cares if a mere water pump fails ? We may decide to run one pump till it fails and then start the standby one. Repair the failed one and reinstall. Why bother to do a monthly PM on that ? This can be one approach.

Reliability is a science by itself. Taking a stuctured approach will return more dividends than usually thought.

Samiran