Square pipe is an important type of square pipe， which has great similarities with seamless steel pipe， but it is different. Square pipe is of great use in square pipe， which is generally used in the field of building materials and pipes. Today we tell you about the painting of square pipe. In fact， most manufacturers need to do this function， not only painting but also galvanizing. Zinc will precede others The base material of the square tube is corroded. If painting is not for you，Large diameter square tube it will cost you two sums of money. If painting，Galvanized square pipe rectangular pipeWhat should be paid attention to in selection it is recommended that you brush zinc rich primer， because you brush other paints， it will corrode quickly， and then continue to corrode your galvanized layer， so as to achieve the finish coat on the zinc rich primer. In fact， you should paint before galvanizing
2Square tube has good machinability， good cold deformation plasticity and weldability; In addition， but it has quite high strength and wear resistance， especially when water quenching; However，Large diameter square tube this steel has great resistance to white spots temper brittleness and overheating during heat treatment.
mB. converter steel: (a) acid converter steel; (b) Basic converter steel. Or (a) bottom blown converter steel; (b) Side blown converter steel; (c) Top blown converter steel.
Soft blowing treatment of molten steel after calcium treatment can reduce residual inclusions in molten steel and better wrap MNS around al CAS and other cores.
LKrivaThe square tube will be tested in many aspects of its performance in the process. Each test is for the square tube to have a good performance in practical application. So what are the different properties of square tubes? Next， Ill introduce the characteristics of the lower tubes in terms of mechanical properties.
NnMechanical property is an important index to ensure the end use performance (mechanical property) of square pipe， which depends on the chemical composition and heat treatment of steel. In the steel pipe standard according to different service requirements， the tensile properties (tensile strength， yield strength or yield point， elongation)， hardness and toughness indexes， as well as the high and low temperature properties required by users are specified.
When cutting， please fix it with square tubes such as vise， and then cut it after it is fixed.
Both internal and external welding of square pipes are carried out by American Lincoln Electric welding machine for single wire or double wire submerged arc welding，Large diameter square tube so as to obtain stable welding specifications.
ePurpose of square tube the purpose of square tube includes construction， machinery，Galvanized square pipe rectangular pipeWhat should be paid attention to in selection steel construction and other projects， shipbuilding， solar power generation support， steel structure engineering， electric products ( pieces)
JThe researchers test before using the strip thinning drawing also confirmed that using the strip thinning drawing can greatly reduce the large value of tangential residual stress of the drawn parts and effectively prevent the occurrence of longitudinal cracking. According to different deformation degree and original sheet thickness， if & psi; If n is too small， the deformation stress will increase sharply resulting in the fracture of the bottom of the drawing part.
MreformCold formed hollow section steel (American Standard) for cold pressed QB square tube (national standard) structure carbon steel cold-formed circular section and pressure welded QB square tube and seamless QB square tube (European standard) non alloy fine grain cold formed welded hollow structural profile (Japanese standard) angle steel QB square tube for general structure galvanized qb square tube for low pressure fluid transmission， Standard No.: gbt-. Representative materials: qqbqb，Galvanized pipe_ Galvanized square pipe_ Seamless steel pipe_ Square tube - Wuxi Jiahang etc. it is mainly used to transport water gas， air， oil and heating hot water or steam. It is a special product manufacturing enterprise integrating R & D， sales and service. It has long been specialized in selling square tubes， square tubes， seamless square tubes， galvanized square tubes and galvanized tubes. It is used for general low-pressure fluids.
jOIt is mainly caused by the fact that the square pipe body has no cover， the covering protection is not ideal， and there is no support， partly due to the excessive number of stacking layers， and most coastal areas belong to marine climate， with large annual rainfall， high air humidity， it shall be protected with an uncovered object from the beginning of storage to avoid rusting， layer aging， there are a lot of demands for project construction， which leads to the continuous increase of square pipe. The of square pipe is more complex. Great efforts should be made in the selection of raw materials， structured treatment and so on.
Performance index analysis fatigue of square tube the strength， plasticity and hardness discussed above are the indicators of the mechanical properties of metal under static load. In fact， many machine parts work under cyclic load， under which fatigue will occur.
retaileroThe disadvantage of solid bending is that it has tensile thinning effect. The actual bending will produce tension at the bending point， and the tensile effect will shorten the longitudinal length of the bending line; The metal at the real bend will become thinner due to stretching.
LHot dip galvanized square pipe is widely used， mainly in curtain wall， solar power generation support， construction， machinery and steel structure engineering， especially in curtain wall， machinery and construction. The effect of cold galvanized square tube is far from that of hot galvanized square tube; How to distinguish hot galvanized square pipe from cold galvanized square pipe?
Hot rolled qb square tube continuous casting slab or blooming slab is used as raw material， heated by stepping heating furnace and descaled by high-pressure water into roughing mill. Roughing material enters finishing mill after head cutting， tail cutting and then computer rolling. After final rolling， it is rolled into straight hair coil through laminar cooling and coiler. The head and tail of straight hair curl are often tongue shaped and fish tail shaped， with poor accuracy of thickness and width， and there are often defects such as wave shape， hem， Q， St-， etc.
Surface adhesion resistance is an important feature of square tubes. At present， square tubes are mostly used for transportation， so the adhesion resistance makes square tubes not stick during transportation.