As the use of square tube
deep underground, in this environment is very easy to be corroded, so much attention to the quality of the square tube without any flaws.
Many shortcomings of the square tube is formed in the perforation in the hollow section so the power transmission process is the production of square tube the key process. High alloy perforation is the primary difficulty when the low perforation function, in order to ensure the quality of the perforation should be a rational choice of deformation parameters. The small amount of tightening will make the perforation process unstable, so the critical tightening amount is about 10% of the initial tightening volume, otherwise it will bite or even move to add the first card. The increase in the front of the head tightening will also constitute the hole cavity and the sound inside the shortcomings so if you want to ask customer questions tube billet must be ambitious, and the centering of the empty depth to compare according to other types of steel. So the criterion of heating is the temperature in the future and the need for heating quality.
The quality of the heating depends very much on the heating operation and heating criteria. A small value of the ovality factor in contrast generally improves the quality of the capillary and can limit lateral deformation. However, the elliptic coefficient is too small or not, it will cause the rolling rotation difficult, and even lead to the guide plate wear and tear, easy to make up the shortcomings of the surface. Therefore, when the boat bar side tube around the check guide plate worn over the situation, once found, immediately replaced, the degree of elliptical probably controlled within 1.07-1.08 scale. Affect the normal operation of the subsequent steps there are square tube billet heating the key processes, which affect the quality of the finished product is also very large.