I recently have run into several drillers who have had problems with the piping from the pump to the swivel. Usually, it is an older rig that may have had a fair amount of rebuilding done, but they somehow neglect to inspect – or replace – the mud lines from the pump to the swivel


Drillers often report problems with the piping from the pump to the swivel. Photo courtesy of the ICDP San Andreas Scientific Drilling Program.


So far, it has been an amazing year for me. My drilling has been considerably less than in the past, mostly because I haven’t pushed it, and it is nearly impossible to find good rig hands who don’t have to be supervised 24/7. If I’ve got to be there, I might as well do it myself! On the other hand, my solids control business is exceeding expectations by a good margin. I’ve got orders well into next year, and am designing custom equipment for several customers. Hope all that keeps up!

As some of you know, my bride of 20 years, Lottie, has quit going to trade shows with me since 9/11. I just couldn’t convince her to get on a plane. From time to time, I’ve gently goaded her to go with me, with no results – until a week ago. She announced that she “just might” go to the NGWA convention in Vegas with me this year! I sure hope so. The good part is that we’ll be able to enjoy a few days together away from work, and she’ll be able to hear me repeat my stories a few hundred more times – no doubt with a lot of eye-rolling and comments like “He’s lying.” The downside of the deal is that I have to provide her with a “stake” to gamble with. I’m going to do it, but I don’t understand why. After all, she’s got a job, money and hasn’t taken a vacation this year, so what’s the problem? I think I might as well try to touch the moon as figure out the feminine mind! Oh well, she puts up with me ….

On a more serious note: I recently have run into several drillers who have had problems with the piping from the pump to the swivel. Usually, it is an older rig that may have had a fair amount of rebuilding done, but they somehow neglect to inspect – or replace – the mud lines from the pump to the swivel. A driller I know plugged the bit, and when the pump pressured up, it blew the pipe out of the tee at the top of the pump, flew back and cut off his finger! I looked at the parts, and most of the pipe was eroded from the inside due to poor or non-existent solids control to the point that schedule 40 pipe was as thin as a paper cup. It’s a wonder it didn’t come apart sooner.


Inspecting the mud lines is important, particularly on older rigs. Photo courtesy of the ICDP San Andreas Scientific Drilling Program.
There are a lot of tees and 90s in the plumbing on the deck of the rig, and when replacing these parts, it is a good idea to think about what they actually do before just screwing in more connections. One thing I’ve noticed on a lot of older rigs is that there is no pressure relief valve in the manifold. Ya gotta remember that most mud pumps are positive displacement pumps driven by lots of horsepower. If something plugs, something has to give. It usually will be: 1) expensive, 2) hard to replace, or 3) dangerous. Get a working relief valve and test it from time to time.

Next, when replacing 90s, try to get long sweep 90s. They cause less turbulence and last much longer that conventional 90s. If you can’t find them, two 45s work almost as well. At the top of the standpipe, instead of two 90s to connect to the kelly hose, I would suggest using a tee facing up with a bull plug in the top. This will reduce erosion caused by the sudden change of direction of the mud. Coming out of the tee, I would use a long sweep ell or two 45s to reduce turbulence and erosion at this critical point.

There are many more areas in the basic rig plumbing that I could discuss, but all rigs are different and mostly what it will take is some planning and a good understanding of what you want the system to do. Sometimes, sitting on a bucket, looking at the rig and thinking about it often is much more valuable than welding and fabricating time that is ill-planned. If I can help you with re-plumbing or remounting problems, e-mail me at rockbit8@hotmail.com – I’ll be glad to help.
ND