I have a lot of friends on social media in the drilling business. We ask each other questions, give answers to questions and generally interact in ways that help build the industry. We don’t always agree. (Do you know any two well drillers who agree on everything?) But it strengthens the depth of knowledge and broadens that strength in the industry. Here, I’m going to talk about a couple discussions I have been involved in recently.
One was a lively discussion that came up about 2-inch wells. Talk about “poking the bear.” Most of the air drillers said they had never heard of them, wouldn’t drill one and wouldn’t work on them. The guys who live and work in mud country know about them, curse them a lot and won’t work on them. Two-inch wells enjoy a small niche in the drilling world. They are not common anymore. In fact, I can’t think of anyone who drills them, but they had a place in the world and served their customers well for years — and in many cases still do.
In my time, I have drilled several thousand 2-inch wells and, while not the most profitable wells, they were generally quick and easy, and a good way to keep the rig running. Most of the customers for them were country folks in the lower to middle income levels, so a deluxe, all-the-way well was out of the question. Many were my friends and neighbors, so I did my best to provide them with reliable water.
The first thing I told them was that, while a 2-inch well certainly was cheaper, it was also much like a disposable lighter: When it breaks or needs replacement, just throw it away and get a new one. There is some easy service that can be done, but major operations like deepening or other downhole services are difficult or impossible.
Since they usually had centrifugal pumps at the surface, that service was about the same as any other well. Since I live in the South, a pitless is not necessary, making installation easier. Also, high water levels make installation much easier, because all you need is a suction line and check valve. With a deeper water level, a packer jet becomes necessary. This is one of the quirks of 2-inch wells. The jet is sealed by “leathers,” a type of packer that makes a seal between the casing and the jet. They are generally reliable, depending on water properties, and fairly easy to service.
The problems arise when it’s time to pull the jet for repair or replacement. Originally, these wells were steel casing with couplings. When pulling a jet, it would come up to the next coupling and the leathers would lodge in the space in the coupling, between the joints of casing, locking you in. Sometimes, you can work the jet up and down enough to wear out the leathers or, if the casing was properly grouted, you might be able to pull enough to “turn” the leathers and proceed. If the well was not properly grouted, it was likely to pull the casing … meaning instant destruction of the well.
As the industry progressed, PVC casing became the norm. It was cheaper, faster and didn’t rust. The same problem occurred with the jets. The jet would come up to a joint, and the leathers would lodge in the small space between the top of the bell and the next joint. This almost always resulted in pulling the casing and ruining the well. However, I discovered a trick to this. When running glued, bell-and-socket casing, I ran the bells on bottom. This created a smoother transition at the joint for the jet leathers to go through. After that, I could easily (for a young guy) pull jets by hand without fear of hanging up the jet in a connection. Like I said, I don’t know if anyone is still putting them in but, if so, this trick will save a lot of hassle at service time.
Another interesting topic also came up recently on my social media: tremie lines. A lot of drillers set their casing and rather than pump grout or cement using the Halliburton method, inside the casing, they run an outside tremie and pump cement or grout from the outside. This works pretty well, provided you have enough room in the hole and the hole integrity to run your tremie. Most guys use PVC tubing. This works if the hole is large enough and doesn’t have too many dog legs or ledges. An improvement on this is to tape the tremie line to the casing as you run it. This helps and saves time, but the same problems can arise.
We discovered a way some years ago to have the best of both worlds. I use lay-flat hose for the tremie. Taped flat to the casing, it takes up very little room and is easy to get below ledges. When you pump the grout, it will burst the tape and free the tremie when you are done. Saves a lot of time and hassle. I just duct tape the very bottom quite a bit extra, and cut a window in it about 2 feet up. The grout goes out the window, the tremie stays in place and a good pull will free it at the end. This also works well with geothermal loops that must be grouted bottom to top. In this case, I run the lay-flat hose between the legs of the loop, so that the grout tends to break the tape and spread the loops to make contact with the walls of the hole. Loops almost always work better in close contact with the formation, rather than in the center of an insulating grout sheath.
I hope these tricks help. Social media can be a very interesting and informative medium, if you can get by all the spam and advertising. If you want, you can find me on Facebook. I’m always glad for conversation or to give free advice. Remember, free advice is worth what you pay for it.
Keep ‘em turning to the right, friends.
For more Wayne Nash columns, visit www.thedriller.com/wayne.