Drill Crossover

Oil Casings: Specification: 4-1 / 2 "-20" Button type: STC (short circle), LTC (long circle), BTC (trapezoidal button), etc.

This type of drill tool joint is threadedly connected to the outer thickening or the inner and outer thickening drill rods to form a drill pipe joint inner diameter, a thickened inner diameter of the pipe body and an inner diameter equal to or similar to the inner diameter of the pipe body. All specifications of the thread use V-0.065 flat top flat bottom triangular tooth shape, variable buckle joint, this tooth type is flat bottom, the width of the top of the tooth is 0.065 inches (1.651mm). Except for 51 / 2IF, the other sizes of threads are interchangeable because their structural dimensions are exactly the same as the corresponding digital threads. This type of thread is easy to cause stress concentration due to its tooth structure. API has eliminated it, including 41 / 2IF and 4IF. They are 410, 411, 4A10, and 4A11, which have been used extensively in our oil field. They are replaced by NC50 and NC number 46 thread.