Cold drawn pipe refers to the bending deion of circular and square shape after welded, surface jointed steel pipe or steel plate. The blank of cold drawn steel tube is used in steel plate or strip. 20 30 century since the 1990s, with the rapid development of high-quality strip rolling production and progress of welding and testing technology, and constantly improve the weld quality, varieties and specifications of cold drawn steel tube increasing, and instead of the seamless steel pipe in more and more fields. Than the cold drawn steel pipe seamless steel pipe with low cost and high production efficiency. 钢管分无缝、焊管。焊管分直缝冷拔钢管、螺旋钢管。冷拔无缝钢管分ERW（高频电阻焊）、LSAW（直缝埋弧焊）。螺旋管焊接工艺也是埋弧焊（简称SSAW）与LSAW 的区别就是焊缝形式，与ERW的区别是焊接工艺的区别，埋弧焊（SAW）是要添加介质的（焊丝、焊剂），ERW不需要，ERW是通过中频加热熔融的。钢管按生产方法可分为两大类：无缝钢管和冷拔钢管。冷拔无缝钢管按生产方法可分为：热轧冷拔无缝钢管、冷拔管、精密钢管、热扩管、冷旋压管和挤压管等。无缝钢管用优质碳素钢或合金钢制成，有热轧、冷轧（拔）之分。
The steel pipe, seamless pipe. Branch pipe straight seam steel pipe, spiral steel pipe. Cold drawn seamless steel tube ERW (HFRW), LSAW (SAWL). Spiral pipe welding technology of submerged arc welding (SSAW) is the difference between LSAW and ERW is the form of welding, the distinction is the welding process, submerged arc welding (SAW) is added to the medium (wire, flux), ERW does not require ERW, is through the interte frequency melting. Steel pipe according to the production method can be divided into two categories: seamless steel tubes and steel pipes. Seamless steel pipe according to the production method can be divided into: hot-rolled seamless pipe, cold drawing tube, precision steel tube, thermal expansion pipe, tube and pipe extrusion cold spinning. Seamless steel pipe made of high quality carbon steel or alloy steel, hot-rolled, cold-rolled (drawn) branch.
The production process of cold drawn seamless steel tube is simple, high production efficiency, low cost, rapid development. The strength of the spiral welded pipe than cold drawn seamless steel tube is high, with a narrow billet production of large diameter pipe, can also use the same width of the billet production of different pipe diameters. But with the same length of straight pipe, weld length of 30~100%, and the production rate is low. Therefore, most of the small caliber pipe welded, large diameter welded pipe mostly using spiral welding.
The spiral steel pipe products and new products of steel plastic composite pipe to hot dip galvanized steel as matrix, the powder melting spraying technology in the wall (wall also need) coated with a plastic, steel pipe with excellent performance. Compared with galvanized pipe, anti corrosion, no rust, no fouling, smooth, clean, non-toxic, long life etc.. According to the test, the service life of steel plastic composite pipe for galvanized pipe is more than three times. Compared with the plastic pipe, has the advantages of high mechanical strength, good heat resistance, pressure etc..
Spiral steel pipes and steel pipes is what is different? There is the two kind of good steel. You don't need to be entangled in this issue. A spiral cold drawn pipe itself is cold drawn steel tube, only in the production process are different. Specifically, according to the weld pipe into the form of cold drawn seamless steel tube and spiral welded pipe. Both the general scope of use is not the same.
Generally more than DN350 with spiral steel pipe, spiral steel pipe weld is because of the spiral, so under the pressure of liquid can be distributed on each side of the tube, to enhance the strength of pipe. At the same time, if the general large pipe directly with steel plate welding for large steel plate, rolled up, greatly increased the difficulty of making, it will use large diameter spiral pipe. As to what is good, because the scope is not consistent, do not have to go.
Spiral pipe (double spiral submerged arc welded pipe) is a strip coil as raw material, often warm extrusion molding, spiral with automatic double wire submerged arc welding process double-sided welded pipe joints. In addition there is a welding steel pipe, it is rolling steel plate after welding, the weld seam. Spiral welded pipe is a steel spiral roll welding, weld spiral.
两者的区别主要有： 1、前者焊缝是一条直线，而后者是一条螺旋角不同的螺旋线。 2、前者每生产一种规格的钢管，就要有一种特定宽度的原料带钢或钢板；后者同一种宽度规格的带钢可以生产出不同直径的钢管。 3、由于焊缝形状的不同，在承受内压时，螺旋焊缝处合成应力是冷拔无缝钢管主应力的60-85%。因此，在相同工作压力下，同一管径的螺旋焊管比冷拔无缝钢管壁厚可减小。 4、在中小直径焊管的生产中，前者具有较大的优势，在大直径焊管的生产中，后者具有绝对优势。
The main difference between the two: 1, the weld is a straight line, while the latter is a helix helix angle different. 2, the production of each steel pipe specifications, there should be a certain width of the strip steel or steel plate; the same width strip specifications can produce steel tubes with different diameter. 3, the weld shape is different, under internal pressure, welding stress is the synthesis of cold drawn seamless steel tube stress 60-85%. Therefore, in the same working pressure, the spiral welded pipe of same diameter ratio of cold drawn seamless steel pipe wall thickness can be reduced. 4, the small diameter of welded pipe production, the former has more advantages in large diameter welded pipe production, the latter has the absolute advantage.
12月11日无锡市场方管价格行情继续下探 | 无锡焊管市场价格回归窄幅波动气氛渐强