弯头,法兰,钢管,管件-沧州皓冠管业有限公司
News

Hot product

Elbow prone to problems and analysis

2019-07-05 16:56:19

1. Lack of penetration: lack of penetration refers to a defect of local infusion between welding elbow and weld metal or weld layer. The lack of penetration weakens the welding seam working section, greatly reduces the joint strength and causes serious stress concentration, which often becomes the root of welding seam cracking.

2, slag inclusion: the weld is sandwiched with non-metallic slag, that is, slag inclusion. Slag inclusion reduces the working section of welding seam, resulting in stress concentration, and will reduce the strength and impact toughness of welding seam.

3, stomata: weld metal at high temperature, too late, when cooling solidification welding pool and internal or surface formation of cavity in the weld, is the porosity, absorbed too much gas (H2), or due to internal welding pool of metallurgical reaction gas (CO), the existence of stomatal work effectively reduces the weld cross section, reduce the mechanical strength of joint. If there is penetration or continuity porosity, it will seriously affect the sealing of welding parts.

4. Crack: during or after welding, the heat affected zone on both sides of the welding seam may also be generated. Local crack of the metal in the welding joint area is called crack.