Method for straightening drill rod

Abstract

The invention discloses a method for straightening a drill rod. The method comprises the following steps of: 1) detecting the initial bending modulus of the drill rod and axially and circumferentially positioning the drill rod needing straightening; 2) obtaining a straightening feeding amount in a computing device through a straightening mathematical model; 3) starting a feed cylinder of a pressure straightening machine to start feeding; 4) as the pressure of an oil inlet loop of the feed cylinder rises when a piercing head of the feed cylinder contacts the surface of the drill rod, when a pressure sensor detects a set value, feeding the set value to the computing device; 5) starting a displacement sensor by the computing device to start detecting the straightening feeding amount; 6) when detecting that the piercing head of the feed cylinder reaches the straightening feeding amount of the straightening mathematical model, rapidly returning the piercing head; and 7) ending automatic straightening control.

Description

Technical field [0001] The invention relates to drill pipe straightening technology. Background technique [0002] Most of the drill pipes produced by the steel pipe factory need to be thickened at the end of the pipe, that is, the two ends are thickened under heating to facilitate the subsequent welding process, so that the diameter of the thickened drill pipe at both ends is different from the middle, resulting in the drill pipe When straightening is performed in the subsequent process, the end straightening cannot be carried out, and the shaft area for the straightening of the drill pipe is formed from the surface. [0003] In order to make up for this straightening area, a drill pipe end pressure straightening process was added after the straightening process. The two ends of the drill rod were specially straightened locally to make the full length of the drill rod meet the API straightness requirements. [0004] The current straightening process method used is manual manual str...

AI Technical Summary

Problems solved by technology

[0005] The purpose of the present invention is to effectively solve the current problems of straightness detection and straightening of drill pipe ends by providing a straightening method for drill pipes, aiming at the defects of human operation judgment of pressure straightening of drill pipes, and improve detection and straightening. High precision and efficiency, while reducing the work intensity of the operator