65galvanizedpipeQ345D seamless square tube

Q345D seamless square tube

Q345D seamless square pipe is a long strip of steel with hollow section and no joint around it.

Steel pipe has hollow section and is widely used as pipeline for conveying fluid, such as pipeline for conveying oil, natural gas, gas, water and some solid materials. Compared with solid steel such as round steel, steel pipe has the same bending and torsional strength and light weight. It is an economic section steel. Q345D seamless square pipe is widely used to manufacture structural parts and mechanical parts, such as oil drill pipe, automobile transmission shaft, bicycle frame and steel scaffold used in construction.

Plasticity

Plasticity refers to the ability of metal materials to produce plastic deformation (permanent deformation) without damage under load.

Hardness

Hardness is a pointer to measure the hardness and softness of metal materials. At present, the most commonly used method for measuring hardness in production is the indentation hardness method. It uses an indenter with a certain geometry to press into the surface of the tested metal material under a certain load, and determines its hardness value according to the degree of indentation.

The commonly used methods include Brinell hardness (HB), Rockwell hardness (HRA, HRB, HRC) and Vickers hardness (HV).

Fatigue

The strength, plasticity and hardness discussed above are all indicators of the mechanical properties of metals under static load. In fact, many machine parts work under cyclic load, under which fatigue will occur. Special shaped steel pipes with other section shapes are also required.