11.Construction method of galvanized steel pipe thread connection?
1). prefabrication; According to bai design drawings, various zhi iron pieces such as steel pipes, du supports, hangers, hoops, etc., as well as various elbow dao are processed. 2). Cutting; Hacksaw, pipe cutter, toothless saw and grinding wheel cutting machine are commonly used in steel pipe cutting. The length of the pipe to be cut is accurate, and it is firmly clamped in the jaw, and the fracture is flush. 3). Threads are unscrewed: the coupling and threads cannot be completely contacted or loosened, so cut off the unscrewed parts and re-install the threads. 4). Conical external thread connection is generally adopted for pipeline threaded connection, and the filler of connection pipe joint is made of hemp silk and white lead oil, and the hemp silk is flax or thread hemp, and polytetrafluoroethylene raw material tape can also be used. Screw tail shall be reserved after tightening, and generally 2-3 threads shall be reserved.
22.Relationship between pipe hoop and steel pipe material?
The manufacturing of pipe hoop is the most delicate, which is the focus of the whole product, because it is the part with large pressure bearing capacity in the whole project. The material requirement of pipe hoop is higher than or equal to the material of seamless steel pipe itself. After cutting from round steel, it is fixed in size by lathe processing, then threaded processing, and finally thread and size inspection.
33.How to check and identify whether the thread sleeve of steel pipe is qualified?
If the snapping knife meets the standard and the installation is qualified, calculate the bottom diameter of the nut according to the drawing requirements. According to the sliding (or slightly larger) fit standard with the bottom diameter of the nut, determine the outer diameter of the screw rod with an outer micrometer; Set the size on vernier caliper according to 10-15 thread pitch, deduct the number according to this size when the first knife passes, and make corresponding adjustment; If all the above items are passed, you can pick the button to the end. (To do this kind of "blind car", you usually trim your teeth thin.)