Sinorock is professional manufacturer in hollow bar micropiles, quality is core factor which can affect the service life of hollow bar micropiles.
Seamless steel pipe is an important material for making self drilling hollow bar micropiles.
As the working conditions and uses of seamless steel pipe is different, which has different requirements for its shape and size, chemical composition, mechanical properties, process performance, other quality indicators and technical conditions. The requirements related to product quality have the following aspects:
1 The chemical composition of steel pipe
The chemical composition of steel tubes is one of the most important factors affecting the performance of seamless steel pipe. In order to improve the uniformity of chemical composition in steel and steel purity, reduce non-metallic inclusions in steel and improve its distribution, which often use furnace refining equipment to refine the molten steel, and even use the electroslag furnace on the tube remelting refining.
2 The geometry accuracy and shape of steel pipe
The geometrical dimensions of the seamless steel pipe include the outer diameter of the steel pipe, the wall thickness, the ellipticity, the length, the curvature of the bend, the cut angle of the pipe end, the groove angle and the blunt edge. These dimensional precisions should be strictly controlled.
3 The surface quality of steel pipe
The standard specifies the “surface finish” requirement of the steel pipe. But the surface of steel pipe defects up to 10 more in the production due to various reasons. Such as steel pipe cracks (cracks), folding, rolling, separation, scarring, pull concave, convex, etc., the degree of damage to the performance of steel pipe is very serious, known as the risk of defects. Such as steel tube pit (face), green line, rub (draw, touch) injury, a slight straight and outside straight, which has less affection on the use of steel pipe, known as the general defects. In order to improve the surface quality of steel pipe, and sometimes shot peening (sand), sanding or machining processing on the internal and external surface of the steel pipe.
4 The physical and chemical properties of steel pipe
The physical and chemical properties of the steel pipe include mechanical properties at room temperature, mechanical properties and corrosion resistance at a certain temperature. In general, the physical and chemical properties of steel mainly depends on the chemical composition of steel, organizational structure, the purity of steel and steel pipe heat treatment methods.
5 The technology performance of steel pipe
The performance of the steel pipe, including steel pipe flattening, flaring, curling, bending, ring and welding and other properties.
6 The microstructure of steel pipe
The microstructure of the steel pipe includes the low magnification of the steel pipe and the high power organization.
7 The special requirements of steel pipe
For special conditions, the use of steel pipes, users tend to put forward some of the special requirements beyond the standard. These special requirements will vary depending on the use of the steel pipe, usually with the contract annex or technical agreement to be expressed.