How to Evaluate Operability and Maintainability

The best bet is to get the operations and maintenance people from an existing facility to participate on the team doing reqular operatability and maintainability reviews.

The other way is to capture the output of these reviews and write standards around operability and maintainability... Things like:

All critical compressors will have an overhead crane and a roof.

A piston compressors will have a clearance or 10 feet around cylinder heads to facilitate piston removal.

Manual valves will be placed such that the valve operator can open or close them in a standing position, with firm footing (on a deck) otherwise alternative actuators will be required (MOVs, chain pulls).

The other possiblity is to buy the standards of another operating company, as most operating companies capture operability and maintainability issues in their standards.

What do you think if I have some proposals from EPC contractors, how can I evaluate the operability and maintainablity of each???

Depends on how detailed the proposals are... What project phase are they writing proposals for?

Probably the best bet is to have them address the issue as part of their proposal. Also assesing their experience will be important to know if they have good background in operability and maintainability. Should not be much of an issue with the major E&C's, it would only be a problem with small contractors...

Don't you consider that operability and maintainability could be used to diferenciate between the EPC contractors even the major ones

No not really... Operability and maintainability are end user driven issues, and each plant or facility will have their own ways of doing things. I would consider the EPC's tools for studying operability and maintainability as differentiating...

Do they have 3D tools to make sure the compressor can be properly maintained?

Do they have process simulators that the operations staff can train on up front?

Those are questions for the proposal stage, not specifics of operability/maintainability.

Some other things to look for:

Physically interchangeable parts should also be functionally interchangeable.

Hydraulic, electric, and other lines should be properly color-coded.

If human strength is not sufficient to change and/or maintain a component, it needs to be accessible to cranes, towmotors, etc.

If the operator cannot see the effect of a control, the system needs an indicator to show the state of component controlled.

The number of different parts should be minimized to reduce spare parts inventory. For example; if one bearing can be used in several places, why use several different ones? Factors such as cost can answer this question, but I'd rather stock one spare part for $50 than one @$50 and one @$25.

I did a Maintainability/Repairability study many years ago, and these are some of the factors I included. If I recall others, I'll add them.

What do you think : if I have four proposals from four different EPC contractors for a new Ethylene Plant, can I generate four reports ,one for each of them, with a final evaluation of the operability and maintainability to be either satisfactory, highly satisfactory or excellent ??? or what do you think ??

All good comments. For more interesting reading on this subject go to:

www.pipingdesigners.com

Click on the "Tips" button and select the article "Thinking Outside the Box"

Hiring a consultant in this field who is not associated with any of the bidding contractors would be within the realm of reason.

Even if there is a consultant, what will be expected when evaluating the operability and maintainability..........Is this leading to someting like satisfactory, highly satisfactory and excellent???

Well if you get someone with long field service, usually a retired engineer, who has truly seen it all, then that person can give you a pretty good idea of what works and what does not in reality, not on paper, as well as what sort of performance and problems to expect.

msalaheldin,

You never really answered my question as to what phase of the project they are proposing. Operability and maintainability decisions are made during detailed design. If the proposals being done are at the beginning of front end development, then the only thing you can evaluate is:

1) The engineering staff: Do they have the experience necessary to design in operability and maintainability? If they are all 5 year engineers, the answere is no.

2) The available design tools: As I said before, do they have 3d simulation tools and process simulators, and other such tools?

3) The Contractors experience, How many ethylene plants have they designed? Who did they build them for?

4) References, can you ask operability and maintainability questions of their other customer for whom they have built ethylene plants?

5) Standards, review their engineering standards and specs for operability and maintainability issues.

Actually, I am talking about a project after completing the basic engineering phase and going to select the most capable EPC contractor for starting thedetailed engineering and go on

Even so the above points are still valid. The biggest question will be around their references.

What I have found recently is that detailed engineering is being done by very young engineers, and that the EPC firms do not have the experience they used to. As a result as we have done large projects (like ethylene plants), we have had to use our experienced engineers to keep a close eye on how the work is developing, especially in the areas of operability and maintainability.

Sad to say, but you probably won't be able to truly asses the EPC's capability until you are in the midst of detailed design. The other thing that has happened to me is what we call in the US a bait a switch. They will supply the CV's of their most experienced people for your consideration, and then when they win the project, that person moves to another job....

Again, find someone who has done work with the companies in question, and ask how they have done...

If you wish you can e-mail me and I will share my experience, assuming the EPC's under consideration are companies I have worked with...

(click on my name above, when the profile screen comes up click on the link "send a message to Steve S.")