Precision steel pipe before welding, precision steel tube after preheating and heat treatment temperature and in the process of welding butt welding a continuous heating to keep the temperature, the welding is completed using Cold Drawn Steel Tubes insulation insulation cotton to make its slow cooling. Quenching can increase the strength and hardness of the steel pipe, But to reduce its plasticity. Is commonly used in quenching of quenching medium such as water, oil, alkaline and salt solution.
Precision steel tube will have quenching tempering precision steel tube, heated to a certain temperature again and again with a certain method of cooling is called tempering. Its purpose is to eliminate the quenching of internal stress, reduce the hardness and brittleness, in order to obtain the desired mechanical properties. High tempering points Temperature tempering, the tempering temperature and low temperature tempering. Tempering and hardening, normalizing, cooperate to use. Conditioning treatment after quenching temperature tempering heat treatment method is called conditioning treatment.
Control of cold drawn steel tube what can adopt method of cold drawn steel tube control mode of the following: cold tensile stress control condition: in cold drawn after as prestressed steel grade of steel and steel, 5 should be cold-drawn in-situ stress control. Little imagine, the reinforcement to carry out the cold After, to examine its larger cold drawing speed is not beyond the standard in the specific values, and to carry out the mechanical kinetic energy test. Cold-drawn rate measurement control rules: control to speed control of cold-drawn Cold Drawn Tubes steel, cold-drawn should be defined according to the test control values. Regulation of the whole experiment process: in the same furnace zhongtong batch must be no less than four specimens. Be sure to according to the requirements in the instructions for cold Each try to carry out tensile stress on the relatively cold pull velocity measurement, and the mean of the specimens as bath furnace. A group of reinforced concrete cold drawing speed. If reinforced high compressive strength, average cold-drawn rate less than 1%, still must be controlled in accordance with the rate of 1% of the cold drawn The cold drawn steel ratio. Of different type of cold-drawn control: according to the mixture and cannot distinguish the reinforcing steel bar, not cold drawing speed can be used to cold, be sure to several connection of cold-drawn steel.
Each cable for cold drawing speed and control ground stress must meets specifications. Cold-drawn precision welded tubes rate control: thoroughly deformation in order to make steel, cold-drawn rate must be moderate control, generally 0.5 1.0 is suitable. In addition, cold-drawn do requirements of in-situ stress And after cold drawing speed, release pressure reinforced after 2 to 3 times, then loose steel, cold drawn out, make steel. Deformation have plenty of time.