Classification of rusty steel pipes
1, classified by production mode
(1) seamless tube cold-drawn tube, extruded tube and cold-rolled tube
stainless steel seamless steel tube
Stainless steel seamless steel pipe is a kind of strip steel with hollow section and no seam around it.
◆ Seamless steel pipe manufacturing technology and process
Smelting > ingot casting > steel rolling > sawing > peeling > perforation > annealing > pickling > ashing > cold drawing > cutting > pickling > warehousing.
◆ Features of Seamless Steel Pipe
From the above process, we can easily see that:
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 technology of this product determines its limitations. Generally, the precision of seamless steel pipe is low: the wall thickness is uneven, the brightness of the inner and outer surfaces of the pipe is low, the cut-to-length cost is high, and the pits and black spots on the inner and outer surfaces are difficult 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.
(2) welding pipes
(a) Gas shielded welded pipes, arc welded pipes and resistance welded pipes (high frequency and low frequency) are classified according to the process.
(b) Straight welded pipe and spiral welded pipe are divided according to weld.
Stainless steel welded steel pipe
Welded steel pipe, referred to as welded pipe for short, is a steel pipe made of steel plate or steel strip after crimping, unit and die forming.
◆ Manufacturing process and flow of welded steel pipes
Steel plate > cutting > forming > sintering > induction bright heat treatment > internal and external weld bead treatment > shaping > sizing > eddy current testing > laser diameter measurement > pickling > warehousing.
◆ Characteristics of welded steel pipes
From the above technological process, we can easily see that: firstly, the product is continuously produced online, and the greater the wall thickness, the greater the investment of the unit and welding equipment, and the less economical and practical it is. The thinner the wall thickness, the lower the input-output ratio. Secondly, the technology of this product determines its advantages and disadvantages. Generally, the welded steel pipe has high precision, uniform wall thickness and high brightness inside and outside the pipe (the surface brightness of the steel pipe is determined by the surface grade of the steel plate), and can be cut at any length. Therefore, it is economical and beautiful in the application of high-precision, medium and low-pressure fluids.
2, according to the section shape classification
(1) circular steel pipe
(2) Rectangular pipes
3, according to the wall thickness classification
(1) thin-walled steel pipe
(2) Thick-walled steel pipe
4. Classification by purpose
(1) Civil pipelines: round pipes, rectangular pipes and flowered pipes, which are generally used for decoration, building and structure.
(2) Industrial pipes: steel pipes for industrial water distribution pipes, steel pipes for main water distribution pipes (drinking water pipes), mechanical structure/fluid conveying pipes, boiler heat exchange pipes, food hygiene pipes, etc. It is generally used in various fields of industry, such as petrochemical industry, paper making, nuclear energy, food, beverage, medicine and other industries with high requirements for fluid media.
Specification and model of steel pipe
Product name specification, model standard name standard number
Steel pipe: φ 6 ~ 630x 1 ~ 50 mm, stainless steel pipe for fluid transportation: GB/T 14976-2002.
Steel pipe: φ 6 ~ 630x 1 ~ 50 mm, seamless stainless steel pipe for structure: GB/T 14975-2002.
Steel pipe: φ 6 ~ 630x 1 ~ 50 mm, stainless steel pipe for boiler and heat exchanger: GB 13296-9 1.
Steel welded pipe: φ 2 19 ~ 1200x3 ~ 20mm, stainless steel pipe for fluid transportation: GB 12770-2002.