In the test， place the sample between two parallel plates and press it evenly to the flattening distance h specified in relevant technical conditions with a press or testing machine at a speed of no more than mmin.
2Ordinary carbon steel is divided into Q Q q SS， # steel， # steel， etc.
pB. tool steel: (a) carbon tool steel; (b) Alloy tool steel; (c) High speed tool steel.
After RH treatment， calcium treatment can reduce sulfur segregation in the later solidification process.
YArlingtonHowever，Galvanized pipe there is a large rate of end in the application of steel pipe，14 galvanized square pipeThe use of products is an indispensable reserve of common sense which is mainly due to the trouble of internal and external treatment. The first question is very crucial， and its external quality is very important
UqThe cutting surface of the square tube shall be true circle， and the cutting line shall be at right angles to the axis of the square tube. Excessive force is the reason for cutting the square tube into flat or oval， so the square tube should be cut with appropriate force.
The square tube is formed by external control or internal control roller.
When processing the square tube， some processes need to heat the seamless square tube. The heating operation in the processing of the seamless square tube plays a very key role in the quality of the finished seamless square tube.
nBrinell hardness (HB)， Rockwell hardness (HRC) and Vickers hardness (HV) are commonly used.
XSample 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.
PInstallation material listSquare pipe， also known as square and rectangular cold-formed hollow section steel，Galvanized pipe is referred to as square pipe and rectangular pipe for short. The allowable deviation of wall thickness of square pipe is f and J qb respectively. When the wall thickness is no more than mm it shall not exceed plus or minus % of the nominal wall thickness. Long term square pipe， rectangular pipe， seamless square pipe， galvanized square pipe， galvanized pipe， old brand， price advantage and quality guarantee! When the wall thickness is greater than mm， it is plus or minus % of the wall thickness， except for the wall thickness of corners and weld areas.
zPElongation after square tube breaking (& sigma;): in the tensile test， the percentage of the length increased by the gauge length of the sample after breaking and the length of the original gauge length is called elongation. In & sigma; Expressed in%.
Performance index analysis of square tube - impact toughness the load acting on the part at a great speed is called impact load，Galvanized pipe and the ability of metal under impact load is called impact toughness.
Square tube is the main type of square tube. It is also very popular in the square tube market. There are many people doing this kind of thing， so there are many in the competition. The future market potential is huge. We should grasp this information well. In addition，14 galvanized square pipeThe use of products is an indispensable reserve of common sense we must learn about relevant maintenance and repair!
whereeIn the process of square pipe， we will conduct a variety of tests on it to ensure that the square pipe can be better used in practice. In order to make better use of large-diameter steel pipe， we will continue to innovate. Lets introduce the main elements contained in the lower pipe. For the martensitic chromium square tube， the main elements affecting the are chromium carbon and molybdenum; For Martensitic chromium nickel square tube， the main influencing elements are nickel， molybdenum， aluminum cobalt， nitrogen and titanium.
ZThe characteristics of square pipe are as follows: the production process of square pipe is simple，Square pipe, square rectangular pipe, seamless square pipe, galvanized square pipe, galvanized pipe - Wuxi Jiahang metal products Co., Ltd the production efficiency is high， the cost is low and the development is fast. The strength of spiral square pipe is generally higher than that of straight seam square pipe. It can produce square pipe with larger pipe diameter with narrow blank， and square pipe with different pipe diameter with blank of the same width. However， compared with straight seam pipe of the same length， the weld length is increased by ~， which will be oriented to the whole country for a long time Individuals and enterprises provide all kinds of square tubes， square rectangular tubes， seamless square tubes， galvanized square tubes， galvanized tubes for door-to-door sales， on-site settlement and honest operation. There are offices everywhere， which can cooperate for a long time. Moreover， the production speed is low. Therefore， most of the smaller square tubes use straight seam welding， and most of the large-diameter square tubes use spiral welding.
The inclusions in the square tube treated with calcium can be denatured well， and the morphology of sulfide in the rolled stock is also improved.
fUpper yield point (& sigma; Su): the large stress before the yield stress of the sample decreases; Lower yield point (& sigma; SL): the small stress in the yield stage when the initial instantaneous effect is not considered.
eTQb square tube the die material selected， resulting in a lot of hard metal points， resulting in adhesion. It specializes in selling square tube， square rectangular tube， galvanized square tube， tool steel for general die can not be used.
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.