The bars with high carbon content have been broken many times, such as 45 × steel shaft, which will break in a short time. It is often impossible to find out the cause of the fracture by sampling and metallographic analysis. That is to say, it is far fetched to find some reasons, not the…
Gas welding and gas cutting is to use the heat from combustion of combustible gas and auxiliary gas as heat source for welding and cutting of metal materials. There are many types of flammable gases, such as acetylene, hydrogen, natural gas, and liquefied petroleum gas (LPG) (mainly propane). The most commonly used gas is…
With the rapid development of electric power industry, high parameter and large capacity units are emerging, which can put forward higher requirements for the high temperature creep performance and stress corrosion resistance of steel pipe materials. For this reason, a large number of researches have been carried out in the world’s major industrial developed countries,…
1. What is welding condition? What does it have? Answer: when welding the surrounding conditions, including: the base material, thickness, shape of groove, joint form, constraint condition, environment temperature and humidity, cleanliness, and in accordance with the above factors and determine the types of welding wire (or rod) and diameter, welding current, voltage, welding speed,…
Basic knowledge 1. What is welding? A: welding is the process by which two or more materials (the same or different) are combined to form a permanent bond between atoms by heating or pressurizing or both. 2. What is arc? A: by the welding power supply, between the two poles to produce a strong and…
One What is acid electrode? Answer: there are many acid oxide electrodes in the coating, such as AC and DC electrodes such as junction 422 (E4303) and junction 502 (e5003). Two What is alkaline electrode? Answer: there are a lot of basic oxides in the coating and fluorides in the coating, such as 507 (E5015)…
Characteristics of argon arc welding of stainless steel sheet (1) the thermal conductivity of stainless steel sheet is poor and it is easy to burn through. (2) welding wire is not required during welding, and the base metal is directly fused. Therefore, the welding quality of stainless steel sheet is closely related to the operator,…
Why is nickel alloy more and more widely used Nickel has good mechanical, physical and chemical properties. Adding suitable elements can improve its oxidation resistance, corrosion resistance, high temperature strength and some physical properties. Welding characteristics and requirements for nickel and nickel-based alloys Cleaning before welding The surface cleanness of welds is an important requirement…
According to their position in the weld, welding defects can be divided into internal defects and external defects. The external defects are located on the outer surface of the weld and can be seen directly. External defects mainly include the size of welding seam is not in line with the requirements, edge bite, welding tumor,…
In the production of large-scale equipment structure, there are often large workpiece quality and volume, which can easily lead to poor welding quality and inaccurate size. Moreover, the welding efficiency is very low and the labor cost is relatively high. How to improve the welding accuracy? This problem has been bothering everyone in the welding…
