Water Well Journal

September 2016

Water Well Journal

Issue link: https://read.dmtmag.com/i/715953

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Page 25 of 81

A s the cost of a drill bit is high, Kevin Christensen always tells his contractor customers one of the quickest and easiest ways to lower the bit cost is by having them retipped. "If you catch your bit in time before you ruin it and send it in to your bit man, you can save 50 percent of a new bit and still have about 85 to 90 percent quality of a new bit," says Christensen, president of Palmer Bit Co. in Williston, North Dakota. "Quality-wise, it's not going to be just like a brand new bit, but we can get it pretty close sometimes." Christensen's staff of five on the shop floor tackle all types of drill bits— from the common drag bit to the tricone bit to the polycrystalline diamond com- pact (PDC) bit. The average life of a bit, especially the drag bit, Christensen says is difficult to estimate. "You could be drilling in soft clay or sand and be drilling forever and be drilling several thousands of feet and hit a boulder and it wipes it out, or you can put on a new one and 30 feet later hit a boulder and wipe it out," he says. "You just have to really take a look at the bit after each hole. If you want to retip your bit, try saving some money and get some better life out of it, you need to take a look at the bit after each hole." Water Well Journal explored this topic further in mid-July by having a discussion with Christensen. Water Well Journal: How can a contractor know when to send their bit in to be retipped? Kevin Christensen: With about 50 percent of the carbide, you can still drill with the bit. Depending on the formations you are in, like clays, you could very easily get another hole. However, in gravels and harder formations like shale, it is better to send the bit in for repair so the bit doesn't lose the pocket the carbide is in. To have a good quality repair, 50 per- cent of the pocket the carbide is soldered in needs to be left. We build the pocket up with steel, remachine it, and then solder a new piece of carbide in. WWJ: What are the reasons contractors elect not to send their bit in to be retipped? Kevin: I estimate 35 to 40 percent of my business is repairing bits. It should be much more than that if drillers were focused on that, but they have to weigh the options because tripping out costs money. They have to decide whether to save bit costs, or do I want to spend an hour coming out of the hole tripping out. It's kind of a juggle on what they want to do. Most of the time, they're going to sacrifice the bit when it comes to drag bits anyway. When it comes to the PDC, when they're 10 times the cost, that's when they're going to take a better look and slow down and take care of that bit. The PDC is extremely expensive, so that is really where we need to focus on getting our customers to repair their PDCs. But like everywhere else, there are good bit shops to repair them and bad ones. I see really bad repair jobs. The PDC is one of the most important bits to repair and take care of. WWJ: What kind of shortcuts have you seen from bit repairs? Kevin: One of the quickest and easiest shortcuts I've seen in my career is instead of taking carbide off and building the body up with steel, they put a piece of carbide on there and build up behind the carbide with brass and grind that brass down and paint it so you can't tell the difference. But brass is so soft, once it hits a little grab they're going to give, crack that carbide, and the life of the bit is reduced. There are a lot of bit tippers out there who are taking short- cuts. And the life of the bit is not what it should be when drillers get it back. Drillers have a bad experience from bit tip- pers and then say, "The heck with it, we're going to continue to buy new bits." WWJ: What can a contractor expect once they send their bit to you? Kevin: From a customer standpoint, once it hits my door, I have a standing rule with my crew: it should be repaired and shipped back out that same day. When my customers are con- scious enough to be sending the bit in for repair, they want them back fast. They don't have a large inventory of drill bits, A step-type drag bit in the process of being retipped. Notice the steel behind the carbide has been built up. When all of the carbide is replaced with new it is ready to be ground and painted. WATER WELL JOURNAL Q&A KEVIN CHRISTENSEN President of Palmer Bit Co. Kevin Christensen waterwelljournal.com 22 September 2016 WWJ

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