Threading Oil Patch Pipe Made Easy

We have a customer who manufactures drill pipe for the oil patch industry, and primarily they repair threads. This means picking up the old, damaged thread (teaching the thread) and then machining off enough material to have a clean, fresh thread.  The old method required quite a few program edits, entering the proper M-codes, etc…  It required quite a few steps by the operator as well. It was slow and cumbersome. They asked us to find a way to reduce the key presses operators use when editing programs and teaching threads, so they could keep their costs in line. They presented the challenge to us: make the process of threading easier to use. I teamed up with Okuma Software Engineer Casey Croussore and started to crunch some numbers.

To make our challenge a bit more….challenging, we learned that this customer typically worked with tapered thread. To repair it, they kept pushing the thread back, but there’s only so far they could go before they scrapped the part. The key here is to get to a sweet spot where you're removing just enough material to repair the thread, but not too much because the more material they take off with each repair job, the fewer repair jobs they’re going to be able to do.

Advanced Thread Phase Matching

In our quest for the easy solution, I handled the mathematical calculations, and eventually came up with a spreadsheet having about 30 different formulas on it, each of them intertwined and interdependent. I handed this off to Casey and he wrote the code that goes in the background to handle my calculations, track variables and so on. His job was to take all of the background calculations and create a user interface on the control that’s simple to use. We spent a lot of time testing and getting the bugs worked out. The result is a machine tool app called Advanced Thread Phase Matching.

Passing the “Easy” Test

With Advanced Thread Phase Matching, when the user runs a part program, he hits a teach button when they have the CNC machine at the correct starting point, then they just press the up or down button to shift the thread further in. Every time he hits a button, the app recalculates everything on the fly, and sets the machine up to be ready to run the thread to their desired point. This is a huge timesaver because they don’t have to manually teach the machine on every pass. We also made it so they could take off any amount of material, which enabled them to double the life of the pipe, or in some cases even better. By using this app there’s a time savings on the machine, and the pipe lasts longer as well.

When the day came to install the app on our customers’ CNC machines, we installed the first one, then went and did three more. Then we came back to show the first operator how to run the app. When we circled back, we saw he was already using it, without us even showing him how! “Easy” accomplished.

Open Possibilities

These days we have a new phrase we’re using here at Okuma: “Open Possibilities.” I think Advanced Thread Phase Matching is a great example of this. Because of the open nature of our CNC machines and controls, the possibilities are endless for how we can help you customize them for your needs. In this case, we’ve made a complicated operation easy for the end user. If you’re re-threading oil patch pipe, I recommend that you contact us or your local distributor to learn how the Advanced Thread Phase Matching app can save you time and make life a bit easier in your shop.

David Fischer is Lathe Product Specialist, Okuma America Corporation.