When cutting the square tube， there will be deformation
When cutting the square tube， uneven incision and crack of the incision. What should we pay attention to when cutting the square tube and how to operate it? Today， I will introduce some problems that should be paid attention to when cutting the square tube. If the correct operation will make the square tube cutting work very smooth， please use a rag or cloth to clean the oil on the surface of the square tube Sundries or soil shall be completely clean.
0Steel with chromium content of more than % in steel and high corrosion of external medium (acid， alkali salt) is called square pipe. According to the condition in steel，Q355b square tube square tubes can be divided into martensite，150 galvanized square pipeWorking principle and main technical indexes of ferrite， austenite and ferrite & mdash; Austenite type， precipitation hardening square tube， according to the standard gb & mdash; regulations， a total of regulations.
uWhen sand blasting or manual mechanical derusting is used， due to the falling off of the oxide scale of the galvanized square pipe， the metal on the surface of the galvanized square pipe is directly exposed in the air. If a primer is not applied in time， the surface of the galvanized square pipe is easy to rust again， affecting the adhesion of the paint film. I am engaged in selling all kinds of square tubes，Q355b square tube square rectangular tubes， seamless square tubes， galvanized square tubes， galvanized tubes and other materials all year round. I operate in good faith. Welcome to call! As the paint is a time-effective material， the main indexes of the paint must be rechecked before use， and the paint can be used only when the results meet the standards.
The strength， plasticity and angle discussed later are the machine function indicators of metal under static load. In practice， many mechanical machines are under repeated load， and the whole opportunity is tired in this environment.
EVictoriaOne of the steps that are prone to defects in the production of square tubes is heat treatment and the other is tensile treatment. Today we need to know the latter. Maybe some people will have a lot of questions about why square tubes are prone to defects in tensile. Now lets analyze the specific causes of defects.
SxWhen cutting the sample， the surface of the sample shall not be damaged，Q355b square tube and the edges at the section shall be rounded.
Material of square tube: q Q (Mn)， #，150 galvanized square pipeWorking principle and main technical indexes of alloy steel， stainless steel.
When the square tube is processed， it needs to be properly polished to ensure durability， smoothness and. There are kinds of polishing for general stainless steel profiles， including mechanical polishing chemical polishing and electrochemical polishing.
qHeat to a temperature hundreds of degrees Celsius below the melting point， which can save energy.
BThe standard number of square pipes for transporting flammable and non flammable fluids is gbt (gbt - represents steel for l-l and other pipelines. It is mainly used for transporting flammable and non flammable fluids， low-pressure or high-pressure square pipes， with high requirements.
MSincere serviceThe selected punch and die fillet has a great relationship with the size and distribution of stress. Large fillet radius
tZThe standard number of spiral square pipe (standard of the Ministry of petroleum) for low pressure transmission is syt-. The representative materials are qbqb and other carbon steel materials. It is mainly used for low-pressure transmission of water，Square pipe, square rectangular pipe, seamless square pipe, galvanized square pipe, galvanized pipe - Wuxi Jiahang metal products Co., Ltd oil， natural gas， petrochemical and other occupations， there are various forms of heat exchangers， but the conventional heat exchangers have many disadvantages， such as poor heat exchange difficult cleaning， which can not meet the needs of production customers. The square tube heat exchanger based on square tube throat has the advantages of excellent heat exchange， easy cleaning， small dust thermal resistance and compact structure.
Square tube flattening test is a kind of test to check the deformation performance of metal tubes (seamless square tubes and rectangular tubes) flattened to the specified size and show their defects. Relevant flattening tests shall be carried out in accordance with relevant provisions of test standards. Requirements for samples samples can be taken from metal pipes with qualified appearance. Generally， sawing is adopted. The inner and outer walls of the pipe shall retain the original surface without any processing. Sample length L & asymp; D (D is the outer diameter of the pipe). When the outer diameter is large， the length l shall not exceed mm. When the outer diameter is less than mm l = mm. When cutting the sample， the surface of the sample shall not be damaged and the performance of the metal shall not be changed due to heating or cold processing. The edge of the section shall be flattened. The flattening test is a test to check the deformation performance of the metal pipe (seamless square pipe and rectangular pipe) flattened to the specified size and show its defects. Relevant flattening tests shall be carried out in accordance with relevant provisions of test standards.
Installation requirementspPerformance index analysis of square tube - plasticity refers to the ability of metal materials to produce plastic deformation without deformation under load.
KThe advantage of empty bending is that it can bend the side length when the real bending cannot be carried out， such as synchronous bending and finishing of the upper side and side of qb square tube. Empty bend can also bend R & amp; amp; lt; .T without fracture of pipe wall.
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， so as to obtain stable welding specifications.
cThe general delivery length of square pipe is mm-mm， mostly mm and mm. The square tube is allowed to deliver short and non fixed length products not less than mm， or in the form of interface tube， but the Demander shall cut off the interface tube when using it. The allowable deviation of the wall thickness of square pipe shall not exceed plus or minus % of the nominal wall thickness when the wall thickness is not greater than mm， plus or minus % of the wall thickness when the wall thickness is greater than mm， except for the wall thickness of corners and weld areas. The weight of short gauge and non fixed gauge products shall not exceed % of the total delivery. For square tubes with a theoretical weight greater than kgm， it shall not exceed % of the total delivery. We have many different ways in square tubes. Different ways make square tubes have different characteristics. According to these characteristics， we can correctly select the appropriate application field， In this way， the use efficiency of square tube can be improved. Next， we will mainly explain the characteristics of pipe cooling technology below. What are the main characteristics of square tubes? Square tube parts have accurate dimensions and smooth surfaces: the dimensional accuracy of cold parts developed at present can reach grade ~ . If ideal ones are adopted， their accuracy is second only to that of fine polished surfaces. Therefore， cold parts generally do not need to be reprocessed， and a small amount only need finishing (grinding).
iIPerformance index analysis of square tube - plasticity refers to the ability of metal materials to produce plastic deformation without deformation under load.
The 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， the appropriate thinning coefficient & psi is selected; N (generally .t ~ .t)， if & psi; If n is too small， the deformation stress will increase sharply， resulting in the fracture of the bottom of the drawing part.