10 means the wall thickness is 10mm, and the commonly used value of mm in domestic steel pipe standards means the wall thickness, such as 159*6 is 6 mm.
And American standard is based on ANSI B36. 10 standard?
Wall thickness grades: Sch 10, Sch20, Sch30, Sch40, Sch60, Sch80, Sch 100, Sch 120, Sch 140, sch160; ?
1)ANSI B36. 19 wall thickness grade: four grades: Sch5s, Sch 10s, Sch40s and Sch80s (commonly used for stainless steel); ?
2) Does the wall thickness of steel pipe mean that some steel pipe standards of China, ISO and Japan are adopted?
3) The wall thickness is expressed by the weight of the pipe, and the wall thickness can be divided into three types:?
A. standard weight tube, expressed by STD?
B. Thickened pipeline, expressed as XS?
C. Extra-thick pipeline, expressed as XXS. ?
For pipes with DN≤250mn, Sch40 is equivalent to STD, DN.
Sch20, on the other hand, has a corresponding grade correspondence table, which can be found out that the American standard thickness of pipes with a wall thickness of millimeters, such as DN200 sch20, is 6.35 mm?
In the standard of Sinopec (SH), sch is also used to indicate the thickness of pipe wall.
Extended data:
Seamless pipe is a kind of long steel with hollow section and no seam around it. There are more than 5 100 factories among more than 65,438 companies in the world, among which more than 260 factories among more than 70 companies in 44 countries produce oil pipes.
Stainless steel seamless steel pipe is a kind of strip steel with hollow section and no seam around it. stainless steel seamless tube
Features of stainless steel seamless pipe:
First, the thicker the wall thickness of the product, the more economical and practical it is, and the thinner the wall thickness, the higher the processing cost. Secondly, the process of this product determines its limited performance. Generally, the precision of seamless steel pipe is low: uneven wall thickness, low brightness on the inner and outer surfaces of the pipe, high cut-to-length cost, and pits and black spots on the inner and outer surfaces are not easy to remove; Third, its detection and shaping must be done off-line. Therefore, it shows its advantages in high pressure, high strength and mechanical structure materials.
Types of stainless steel pipes:
Rolling methods include hot rolling, hot extrusion and cold drawing (rolling) of stainless steel pipes.
According to the different metallographic structure of stainless steel, it can be divided into semi-ferritic semi-martensitic stainless steel tubes, martensitic stainless steel tubes, austenitic stainless steel tubes and austenitic-ferritic stainless steel tubes.
Specification and appearance quality of stainless steel pipes;
A According to GB 14975-94 Seamless Stainless Steel Pipe, the usual steel pipe length (indefinite length) is 1.5 ~ 10m for hot-rolled steel pipe and 1m for hot-extruded steel pipe. The wall thickness of cold-drawn (rolled) steel pipe is 0.5 ~1.0 ~ 7m; ， 1.0 ~ 7m； If the wall thickness is greater than 1.0mm, it is 1.5 ~ 8m.
B, 45 kinds of hot-rolled (hot-extruded) steel pipes with diameters of 54 ~ 480mm * * * * 36 species with wall thickness of 4.5 ~ 45 mm * * *. 65 kinds of cold-drawn (rolled) steel pipes with diameters of 6 ~ 200mm * * *; The wall thickness is 0.5 ~ 2 1mm * * * 39 kinds.
C. There shall be no cracks, folds, cracks, cracks, rolling injuries, delamination and scarring on the inner and outer surfaces of steel pipes. These defects shall be completely removed (except for pipes used for mechanical processing), and the thickness and outer diameter of the removed rear wall shall not exceed negative deviation. Other minor surface defects not exceeding the allowable negative deviation may not be removed.
D, the allowable depth of the straight line. Hot-rolled and hot-extruded steel pipes with a diameter less than or equal to 140mm should not be greater than 5% of the nominal wall thickness, and the maximum depth should not be greater than 0.5mm；; Cold-drawn (rolled) steel pipes should not be greater than 4% of the nominal wall thickness, and the maximum depth should not be greater than 0.3 mm. ..
E, steel pipe ends should be cut into right angles, and deburring.
Generally, seamless pipes are made of high-quality carbon steels such as 10, 20, 30, 35 and 45, low-alloy structural steels such as 16Mn and 5MnV, or combined steels such as 40Cr, 30CrMnSi, 45Mn2 and 40MnB. Seamless pipes made of low carbon steel, such as 10 and 20, are mainly used for fluid transportation pipelines.
Seamless tubes made of medium carbon steels such as 45 and 40Cr are used to manufacture mechanical parts, such as those of automobiles and tractors. Generally, seamless pipes should be used to ensure strength and flattening test. The hot-rolled steel pipe is delivered in hot-rolled state or heat-treated state; Cold rolling is delivered in heat treatment state. Seamless pipes for medium and low pressure boilers: used to manufacture various medium and low pressure boilers, superheated steam pipes, boiling water pipes, water wall pipes and superheated steam pipes, large smoke pipes, small smoke pipes and arch brick pipes for locomotive boilers.
High-quality carbon structural steel seamless tubes are hot rolled or cold rolled (drawn). It is mainly made of 10 and 20 steels. In addition to ensuring chemical composition and mechanical properties, water pressure test, crimping, flaring and flattening test must also be carried out. Hot rolling is delivered in hot rolling state, and cold rolling (drawing) is delivered in heat treatment state. Jiangyin Lubao Pipe Industry Co., Ltd. provides the theoretical weighing method of seamless pipe: the theoretical calculation formula of seamless pipe: (outside diameter-wall thickness) × wall thickness ×0.02466= weight of seamless pipe per meter {kg}
References:
Baidu encyclopedia-seamless tube