In order to improve the corrosion resistance of steel pipe， the general steel pipe (black pipe) is galvanized. The galvanized pipe is divided into hot-dip galvanizing and electric steel zinc. The hot-dip galvanizing layer is thick and the cost of electric galvanizing is low， so there is galvanized pipe.
6Welded thin-walled pipe: mainly used for making furniture， toys， lamps， etc. In recent years，Products Show thin-walled tubes made of stainless steel strip are widely used，ColonCombien coûte l'acier I personnalisé?Vérifier such as high furniture， decoration， fence and so on.
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On the other hand， when the steel structure changes during heat treatment， that is， austenite transforms into martensite， the increase of specific volume will be accompanied by the expansion of workpiece volume， and each part of workpiece will undergo phase transformation successively， resulting in inconsistent volume growth and structural stress. Due to the change of tissue stress the tensile stress on the surface and the compressive stress in the heart are just opposite to the thermal stress. The magnitude of microstructure stress is related to the cooling rate，Products Show shape and chemical composition of martensitic transformation zone materials.
HShunhua Polished stainless steel pipes shall be subject to internal inspection and strict manual selection by the steel pipe quality inspector through metal detector (or hydrostatic test)， and qualified products shall be packaged and delivered.
QmCharacteristics and application of galvanized pipe
Pipelines of various specifications and models are complete.
There are several ways to clean galvanized pipes
wIt is a potential rolled strip steel with rectangular section for general purpose. It is very common on construction sites. Its specifications are expressed in thickness and width. At present， most of the flat steel on the market are finished steel， which can be used ready-made for components， ladders， bridges and fences. Flat steel can also be used as blank for welding rigid steel and slab for laminated thin plate.
UThe fifth is the welding environment control to ensure that the temperature， QA， B steel and steel， with a diameter of -mm. There are certain requirements for pipe tortuosity， water pressure and flattening tests are carried out.
yE The cold-rolled stainless steel pipe has the advantages of large yield coefficient，Products Show no expansion bending and so on. In order to reach the health grade standard of stainless steel pipeline， the pipeline after cold rolling must undergo bright annealing，ColonCombien coûte l'acier I personnalisé?Vérifier demagnetization， pickling calibration and other procedures.
Welded thin-walled pipe: mainly used for making furniture， toys， lamps， etc. In recent years， thin-walled tubes made of stainless steel strip are widely used， such as high furniture， decoration，Reinforcement, galvanized pipe, seamless pipe, welded pipe, alloy pipe, I-beam-Shandong Kaiwen metal material Co., Ltd fence and so on.
Galvanized pipe， also known as galvanized pipe， is divided into hot-dip galvanizing and electro galvanizing. The hot-dip galvanizing layer is thick， the coating is uniform， the adhesion is strong and the service life is long. The electroplating cost is low， the surface is not smooth， and the corrosion resistance is worse than that of hot dip galvanized pipe.
Sales DepartmenteSince the s， with the rapid development trend of high-quality hot strip mill production and the development of electric welding and testing technology， the welding quality has been continuously improved， the types， specifications and models of welded steel pipes are increasing， and seamless pipes have been replaced in more and more industries. Welded steel pipes are divided into straight seam welded pipes and spiral welded pipes according to the way of welding. Classified by production mode: classified by processing technology - electric arc welded pipe， resistor welded pipe， (high frequency， low frequency) gas welded pipe， furnace welded pipe.
BIn order to make the steel pipe workpiece have the required mechanical， physical and chemical properties， in addition to the reasonable selection of materials and forming processes， the heat treatment of steel is the main content of metal heat treatment. In addition， aluminum， copper magnesium， titanium and their alloys can also change their mechanical， physical and chemical properties through heat treatment to obtain different service properties.
Longitudinal welded pipe has the advantages of simple production and processing technology， high production efficiency， low cost and rapid development trend. The compressive strength of spiral welded pipe is generally higher than that of straight welded pipe. Narrow blank can be used to produce welded pipe with large pipe diameter， and blank with the same total width can also be used to produce welded pipe with different pipe diameter. However， compared with the straight seam pipe with the same length， the welding length is increased by ~ ， and the production rate is low.
iSanto Domingo Polished stainless steel pipes shall be subject to internal inspection and strict manual selection by the steel pipe quality inspector through metal detector (or hydrostatic test)， and qualified products shall be packaged and delivered.
uBIdler pipe: it is used for electric welding steel pipe of idler of belt conveyor. It is generally made of Q， B steel and steel， with a diameter of -mm. There are certain requirements for pipe tortuosity， end face straightness with the center line and ovality. Generally， water pressure and flattening tests are carried out.
Spiral welded pipe: it is made by rolling low-carbon structural steel or low-alloy structural steel strip into pipe blank according to the viewpoint of certain spiral line (called forming angle)， and then welding the pipe seam. It can produce large-diameter steel pipe with narrow strip steel. Spiral welded pipe is mainly used for oil and natural gas transportation pipeline， and its standard is expressed by outer diameter * wall thickness. Spiral welded pipe has single-sided welding and double-sided welding. The welded pipe shall ensure that the hydrostatic test