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The weld can maintain high strength, exceeding the strength required by the welding material code and application. In many cases, this weld strength can not be identified by the welding material code itself.

Continuous casting method, also known as heat-type continuous casting method. Absolutely prevent melt-type wall nucleation, the mold is heated to a temperature above the solidification of the melt. Solidification of the melt from the mold only at the moment will be. With the continuous slab leaving the crystallizer, along the direction of the solidification of the melt in the heat flow in the opposite direction but it is heated to a temperature above the metal to be cast above the liquidus temperature, performed. T

Technologies for Production of Seamless & ERW Pipes 鈥淐PE鈥� Technology鈥� used for Seamless Pipes& Tubes Production up to 7-inches OD is the world renowned Technology. 鈥淧lug Mill鈥� Technology used for Higher Dia. Seamless Pipes & Tubes Production from 7-inches to 14-inches,is the most reliable technology,in higher dia. Segment. High frequency Induction Welding Technology is used for ERW Pipes &Tubes upto 21-inchesOD.

Welded steel pipe for fire fighting means for fire safety, fire-fighting equipment, transport fire extinguishing water, gas pipeline or other media material. As the fire pipeline is normally in a quiescent state, and more stringent requirements for the pipeline, the pipeline needs to pressure resistance, corrosion resistance, high temperature performance. his pipe use less time and frequency, working pressure is bigger.

Carbon steel is steel in which the main interstitial alloying constituent is carbon in the range of 0.12鈥�2.0%. The American Iron and Steel Institute (AISI) definition says:

The main defects that may appear in the process of submerged arc welding are not only insufficient penetration, burn through and poor forming, but also porosity, crack and slag inclusion. This paper mainly introduces the causes and preventive measures of porosity and slag inclusion.

In the process of high-frequency induction welding, especially in the production of products with thick wall and small diameter, such as small pipes of 1 inch and below, the wall thickness is relatively thick. Generally, we will encounter a particularly wide heat affected zone at the weld, exceeding 1 / 3 of the pipe diameter arc surface, or even 1 / 2 of the pipe diameter arc surface. If the pipe diameter is small, the whole pipe will even turn red, It will adversely affect the final welding performance requirements of some products, and even lead to waste products.

During welding, for the part where there is no complete fusion between the weld bead and the base metal or between the weld bead and the weld bead, the incomplete fusion can be divided into groove incomplete fusion, weld bead incomplete fusion and weld root incomplete fusion. According to the different components, it can be divided into white incomplete fusion and black incomplete fusion.

Hot dip galvanized steel processing will be part of the lubricant remains in the inner and outer surfaces, after annealing in the hot dip galvanized steel surface will form a carbon film in 1980 has galvanized experts on the surface of the carb鈥媜n steel pipe a lot the study proposed carbon galvanized tube life will be adversely affected. Although since then there is no final conclusion on quantitative indicators of carbon steel pipe life impact and influence of carbon, but carbon on hot dip galvanized steel harmful but agreed to eliminate the carbon surface of the tube, it became a hot-dip degreasing zinc processing an essential part.

drilling for oil is a difficult thing in winter, the temperature is too low, ordinary steel pipe to transport trouble, so the general use of anti-corrosion pipe insulation, pipe insulation is a kind of corrosion resistance of steel, and has a good insulation performance, construction has been widely

pipeline corrosion reasons: 1, poor construction quality coating; 2, soil properties through lots of different pipes, easy to form an oxygen concentration cell, so that part of the pipe section appear localized corrosion; 3, anti-corrosion layer mending failure, a serious impact antiseptic quality;

acid or liquid flux never welded parts to penetrate in the galvanizing process, this liquid oozing after galvanizing, resulting in non-galvanized zinc or zinc dissolution.temperature difference caused by the uneven distribution of thickness, the thermal expansion or contraction caused not only plate