Different quality grades shall be selected according to the importance of the structure, load characteristics, weld form, working environment and stress state, etc., according to the following principles: 1. In the components requiring fatigue calculation, all butt welds should be fully welded, and their quality grade is: 1) For transverse butt welds or t-shaped butt…
I. Guarantee project 1. Welding materials shall meet the design requirements and relevant standards, and quality certificates and baking records shall be checked. 2, the welder must pass the examination, check the welder corresponding welding conditions of the certificate and the date of assessment. 3. Grade ⅰ and ⅱ welds shall be inspected by flaw…
A joint with an Angle between the surfaces of two welds greater than or equal to 135° and less than or equal to 180° is called (A). A. butt joint B. t-joint C. lap joint D. Angle joint (302) Electric shock accidents can be divided into direct shock and (B). A. Indirect shock B. indirect…
LNG ship: also called LNG ship, referred to as “LNG ship”. It refers to a “ship” that specializes in transporting LIQUEFIED natural gas. The earliest LNG carrier was the 5,100-square-meter Methane Lightor, which was converted from an old tanker in 1958. According to the structure of liquid cargo tank can be divided into independent storage…
Argon arc welding handle, mop, internal wire filling, external wire filling, arc starting, welding, arc closing Argon arc welding operation: argon arc is a kind of left and right hand operation at the same time, which is the same as the left hand drawing circle and the right hand drawing square in our daily life.…
Instructor: Mr. Bai Jinsheng, Deputy director/chief expert of Special Welding Service Center of China National Defense Technology and Industry, distinguished professor/professional leader of Tianjin Sino-German University of Applied Technology. 1. Question raising Energy Institute of Tianjin Sino-German University of Applied Technology developed China’s special weapons and equipment, and encountered mechanical connection between graphite electrode and…
Hot air welding is also called hot air welding. Compressed air or inert gas (usually nitrogen) is heated to the desired temperature by a heater in a welding torch and sprayed onto the plastic surface and welding strip so that the two are fused and combined under moderate pressure. Oxygen sensitive plastics (such as polyphthalamide)…
1. Oxide film: Aluminum in the air and welding is easy to oxidize, the alumina (Al2O3) high melting point, very stable, not easy to remove. Hinder the melting and fusion of the base metal, the ratio of the oxide film is significant, it is not easy to surface, easy to produce slag inclusion, not fusion,…
In the production of oilfield construction units, welding of magnetized pipeline is often encountered, because of the large magnetic deflecting blowing during welding of magnetized pipe. Poor weldability. This paper mainly introduces the magnetized tube using dc degaussing electrode arc welding, or ac degaussing electrode arc welding, and by means of electromagnet or permanent magnet…
Molten pool temperature, directly affect the welding quality, molten pool temperature is high, molten pool is larger, hot iron flow is good, easy to fuse, but too high, hot iron easy to drip, single-sided welding double-sided formation of the back easy to burn through, forming welding tumor, forming is difficult to control, and joint plastic…
