ERW Steel Pipe

　　Tube billet heating temperature for the seamless tube manufacturer refers to the tube blank discharge temperature. It should be determined to ensure that the steel is subjected to the main deformation within the best range of plasticity. The basis for determining the heating temperature is the iron and carbon balance diagram. In practice, the following factors should generally be considered. 　　1. Steel grade. Different steel grades correspond to their different heating temperatures. 　　2. Temperature drop. The temperature drop (outer) of the new product from the ring heating furnace to the rolling mill process line should generally ensure that the metallographic structure before the end of deformation is in the single phase zone. 　　3. Heating defects. The slab should be prevented from overheating or even overheating. 　　 http://www.xysteelpipe.com/info/Seamless-tube-billet-heating-temperature-1415-1.htm

　　Faced with a large number of 20# seamless steel pipes , for some friends who are not very familiar with 20# seamless steel pipe, there will inevitably be some problems in the process of purchasing. Here are some tips on how to buy 20# Seam steel pipe. 　　In terms of quality, you can start with the fullness of color and hole type. You need to know that the inferior 20# seamless steel tube color is light red, and the hole shape also shows an elliptical state. If it is in the process of purchase, it is found that such 20# seamless steel pipes should not be purchased. Carefully observing the surface of 20# seamless steel pipe, the surface of the inferior 20# seamless steel pipe is not flat. It often carries some burrs. In the process of purchasing, you can also use your own hands to draw the surface of the steel pipe. Do not buy if there are scratches, because the high quality 20# seamless steel tube has strong toughness and wear resistance, sharp objects can not scratch it. Perhaps you...

　　Preheating is required before welding important components, alloy steels parts and thick parts. The main role of preheating before welding is as follows: 　　(1) Preheating can slow down the cooling rate after welding. It is conductive to the diffusion of hydrogen in the weld emtal escape. Besides, it can avoid to hydrogen-induce cracking, reduce the weld and heat affected zone hardened to improve the crack resistance of welded joints. 　　(2) preheating can reduce the welding stress. Uniform local preheating or integral preheating, the temperature difference (also called temperature gradient) between the workpiece to be welded in the weld zone can be reduced. In this way, on the one hand to reduce the welding stress, on the other hand, reduce the welding strain rate, help to avoid welding cracks. 　　(3) preheating can reduce the binding degree of welded structure, to reduce the degree of constraint is particularly obvious, with the preheating temperature increases, the incidence o...

　　How to Choose the SSAW Carbon Steel Pipe Manufacturer 　　Usage of SSAW carbon steel pipe is relatively high, the application is very wide, it should be how to choose before in the selection to pay attention to quality. 　　The first method is a more professional detection method, that is, by the strength of the pressure vessel to be detected. Commonly, we use atmospheric pressure and water pressure to detect, in this way can detect the working conditions of the SSAW carbon steel pipe in the pressure working environment, but also to detect the tightness of the spiral steel pipe, generally take the atmospheric pressure detection, because such security Relatively high, and if the water vapor pressure through the test, then the need to remove the spiral pipe after the water, too much trouble. 　　The second method is also relatively simple, that is, through the surface of observation. With the naked eye found in the spiral steel pipe in the welding and size of the problem, if necessary...

　　 Welded steel pipe production process is a steel sheet, strip, and other various molding methods using the straight press roll or helical direction curling into a desired cross-sectional shape, and then by means of heat, pressure, different methods of welding weld together to obtain steel. Therefore, defects in the welded steel pipe is divided into two parts: the steel base material defects and weld defects. 　 　1. Steel base material defect 　　The sheet material defects after rolling and other processes, most of planar, parallel to the surface; their main weakness delamination, inclusions, cracks, folds, etc., which is the most common layered internal defects. Stratification will produce a variety of cracks when the tensile stress perpendicular to the surface of the sheet by the hierarchical will seriously affect the strength of the steel pipe, it is not allowed defects 　　 2. Weld defects 　　Weld defects refers to defect during welding or after welding resulting in the weld is...

　　The purpose of tempering stainless steel tube is to transform quenched martensite into tempered martensite, eliminate retained austenite, reduce and eliminate internal stress, obtain high hardness, wear resistance and red hardness, stabilize dimensional and improve mechanics. Its performance to meet the needs of its work. Generally, the tempering temperature is generally between 540 ~ 570°C, and it is kept in the 100% KNC)3 salt bath for 1 to 1.5 hours. Due to the tempering of high-speed steel, the fine carbides of W, Mo and V are precipitated in the martensite, and the residue remains. Austenite transforms into martensite during the III fire process and therefore has a "secondary hardening" phenomenon, which should be tempered three times. 　　In order to ensure the tempering effect of high speed steel, the following issues should be noted: 　　1.After the stainless steel tube is quenched, it should be tempered immediately, otherwise the retained austenite will be stabiliz...

　　Natural gas pipeline refers to the pipeline that transports the natural gas (including the production of oil associated gas) from the mined land or processing plant to the city gas distribution center or industrial enterprise users, also known as gas line. In the world pipeline overall length, natural gas pipe accounts for about half. 　　The steel pipe is the main material of the natural gas pipeline. Modern gas gathering lines and gas line are made of steel pipes those connected by welding. There are various kinds of steel pipe, including seamless steel pipe, spiral welded pipe, longitudinal welded pipe. Seamless steel pipe be appropriate for natural gas pipe that the diameter is below 529mm, and spiral welded pipe and longitudinal welded pipe are suitable for large diameter pipe. 　　Features of natural gas pipeline: 　　(1) The gas line system is a continuous closed conveyor system. 　　(2) From the transport, storage to the user, natural gas is with high pressure. 　　(3) Due t...