Increasing Mean Time Between Failure on Hydrogen Reciprocating Compressors

John Gobert
Tags: compressor lubrication

In 2000, I was asked to take a position in a lubrication program that the rotating equipment reliability (RER) group of my company wanted to start. My background included 30 years as a machinist, so this role would be a new field of work to me.

After talking to the RER department supervisor, I accepted the position. My supervisor let me know that he understood that I would need the necessary training in this field and that he would make sure I'd receive this training. He also communicated that he knew little about this field and that it was my responsibility to be able to set up and run the program.

Studying Failures
After attending school and receiving on-the-job training, I began looking at a problem on our hydrogen reciprocating compressors which had a history of failing every three to four months. The biggest problem was that the valves were failing. Every time the compressor valves came into the machine shop after failure, they were caked with a gooey black substance. Of course, this required the machine to be blanked and the unit to cut back on production while waiting to be repaired.

Previously, we assumed that dirty hydrogen was the main cause of these deposits. However, I considered the possibility that it may be the cylinder oil causing this problem. I talked to the vendor of this oil product and was told that it was not experiencing any problems of this nature; therefore, it shouldn't be a problem with this oil. This oil was a full-synthetic product.

A Second Opinion
I then talked to our other oil vendor about what type of oil he would recommend for this application. He recommended one of his synthetic oils, which was a polyalphaolefin (PAO) oil. I decided to make the change to this oil after consulting with my RER group about the possibility of the oil causing abnormal accumulation on the valves, forcing them to quit working and, ultimately, halting the machine.

We switched to the different oil in the machine and, at the same time, also changed to a different style valve. After operating this for more than a year, we pulled a couple of the valves from the machine and found them to be so clean that you would not even have to wash them to be able to reuse them.

Since that time, we've changed to this particular cylinder oil in all of our hydrogen reciprocating compressors with great success. Some of these machines have been operating for more than two and a half years with no repairs. Needless to say, this has been a great savings to our refinery in the areas of labor, materials and lost production.

This case is just one example of many savings that we've been able to achieve because of our in-house lubrication program. This includes educating our employees throughout the refinery on the importance of the lubricants that run our equipment. They now understand that the lubricants are as important as the blood in our bodies. They realize that it is the source of helping machines to be in good working condition and the source to let us know if processes are not going right.

Because of all the improvements and successes with our lubrication program, the company supports our efforts completely. I now have a co-worker working with me full time, and we've bought some new high-tech equipment for the laboratory. We've set high goals for the coming year, and I believe that we will continue to improve the program. I highly recommend that operators of rotating equipment that requires a lubricant start their own in-house lubrication program. It can only improve the equipment performance and improve the savings to the company.

About the Author

John Gobert retired as a lubrication analyst from Valero. He now works as an equipment reliability specialist for The Hurt Company.