ERW Steel Pipe

　　Butt weld elbow is formed by hot forming or forging forming elbow, and its connection is the form of butt welded directly to the pipe. Butt elbow according to its radius of curvature to points, can be divided into long radius butt welding elbow and short radius elbow; Press the pressure level to points, about seventeen, and the United States is the same standard pipe, one of the most commonly used is STD and XS two; according to the angle of the elbow points, a 45-degree butt welded elbow, a 90-degree butt elbow and 180-degree butt elbow and other elbows at different angles; Materials are divided into: carbon steel elbow, alloy steel and stainless steel elbow. 　　Butt welding elbow production process 　　1. Select the appropriate steel, cutting, cutting out elbows model map 　　2. Select the appropriate mold, the pressure on the tablet, into a half-bend. 　　3. The two half-piece bend together, welded together. 　　4. Due to the presence of weld, according to the need to polish the ...

　　1. Stainless steel tube with vertical external power supply, DC positive polarity (wire connected negative). 　　2. Generally suitable for 6mm thin plate welding, weld appearance, a small amount of welding deformation. 　　3. The shielding gas is argon with a purity of 99.99%. When the welding current is 50-50A, the argon flow rate is 8-0L / min. When the current is 50-250A, the argon gas flow rate is 2-5L / min. 　　4. Tungsten protruding from the gas nozzle length to 4-5mm is better in the fillet welding and other poor shielding is 2-3mm, where the deep groove is 5-6mm, the nozzle to the work of the general does not exceed the distance 5mm. 　　5. To prevent the emergence of welding pores, stainless steel pipe welding rust, oil, etc. must be cleaned. 　　6. Welding arc length, welding ordinary steel, preferably 2-4mm, while welding stainless steel tube, 3mm is better, too long, then the protection effect is not good. 　　7. Docking primer, in order to prevent the back of the botto...

　　As the use of square tube deep underground, in this environment is very easy to be corroded, so much attention to the quality of the square tube without any flaws. 　　Many shortcomings of the square tube is formed in the perforation in the hollow section so the power transmission process is the production of square tube the key process. High alloy perforation is the primary difficulty when the low perforation function, in order to ensure the quality of the perforation should be a rational choice of deformation parameters. The small amount of tightening will make the perforation process unstable, so the critical tightening amount is about 10% of the initial tightening volume, otherwise it will bite or even move to add the first card. The increase in the front of the head tightening will also constitute the hole cavity and the sound inside the shortcomings so if you want to ask customer questions tube billet must be ambitious, and the centering of the empty depth to compare according...

　　Circular hollow sections should pay special attention when welding. When welding, pay attention to seamless docking. There is no gap in the joint requirement, and it should be docked. Below we mainly look at how a lower circular hollow sections is welded? 　　Circular hollow sections is widely used in engineering construction, machinery manufacturing, steel construction projects, shipbuilding, solar power generation bracket, steel structure engineering, in addition, circular hollow sections are also used, for example, in the engineering installation industry, such as curtain walls, welded structures, and grid structures. 　　In order to ensure the strength after docking, a cross-ribbed plate may be welded in one of the circular hollow sections, and the circular hollow sections is beveled at the butt joint for penetration. When docking, it can be spot welded to another rectangular tube or H-shaped steel to maintain the straightness after docking. 　　Welding is not as small as possibl...

　　 Square tube quality must control the brightness after annealing. More influential factors are as follows: 　　1, The annealing temperature reaches the specified temperature. Stainless steel tube heat treatment is generally taken by solution heat treatment, which is commonly known as the "annealing", the temperature range of 1040 ~ 1120 ℃ (Japanese standard). You can also observe through the annealing furnace observation hole, annealing the square tube should be incandescent, but did not appear softening sagging. 　　2, Annealing atmosphere. Pure hydrogen is generally used as the annealing atmosphere, the atmosphere is the best purity of 99.99% or more, if the atmosphere is the other part of the inert gas, the purity can be lower, but absolutely can not contain too much oxygen, water vapor. 　　3, Furnace sealing. Bright annealing furnace should be closed, isolated from the outside air; the use of hydrogen as a protective gas, only one exhaust port is open (used to ignite ...

　　In general 304 stainless steel tube mills polishing wheel speed of 2500m / min, the polishing considerations also used in polishing, using the polishing tape 150 to 240 to obtain a continuous hairline surface processing line. In order to achieve the mirror polishing need to use fine abrasive gradually polished, and finally with a very fine polishing paste polishing. 　　 304 stainless steel tube plant in the wipe on the surface of the pipe, the operation is generally divided into two steps for the first polished shine polishing the second colored polishing. Fine polishing scratches left front rub polishing wheel with a light cut, the abrasive stick to the grinding wheel, but the wheel is rotated about the rub on the cutting lubricant, more viscous lubricants. The cutting lubricant is made of artificial abrasive (eg alumina) with a fine particle size of about 300 and hard grease as a binder. They saturate the cloth wheels. The same applies to the pigmented and blanched wipes, except ...

　　Residual stresses caused by uneven cooling of seamless square tubes . Residual stress is the internal self-equilibrium stress in the absence of external force. Hot-rolled steel of all kinds of cross-section has such residual stress. The larger the general section size of steel, the greater the residual stress. Although the residual stress is self-balanced, the performance of steel components in the external force or have a certain impact. Such as deformation, stability, fatigue and other aspects may have adverse effects. 　　Draw the seamless square tube process: Because the size of the extubation die hole is smaller than the outer diameter dimension of the seamless square tube before drawing (except expansion and contraction), in order to make the front end of the seamless square tube smoothly in order to make the clamping jaws of the drawn car clamp the head of the seamless square tube, the head of the seamless square tube needs to be pointed before the drawing to this end, the sea...