Butt welding elbow is one of the pipe fittings, elbow pipe fittings are used in the process of pipeline engineering construction is becoming more common, this is largely due to its forming good, strong compression ability, simple welding form etc., to ensure the bearing capacity of the pipe, so in the process piping engineering especially in petrochemical and flammable and explosive pipe of high temperature and high pressure, the rational use of pipe and pipe fittings itself quality directly plays an important role. Butt welding elbow is applied to the butt welding of ring artifacts such as car rim and bicycle, motorcycle rims of butt welding, butt welding of various link, etc. Butt welding elbow is applied to parts of compound will be roughly rolling, forging, stamping or machined parts butt into major parts of the eve, with a low completion. Such as car mark purpose shaft shell and the rear axle shell butt welding, butt welding of various connecting rod, rod, as well as special parts of butt welding and so on. But in the process of application, prone to all kinds of problems:
A, the uneven wall thickness of pipe fittings
In pipe wall thickness uneven occurs mainly at the site of the largest pipe deformation. Such as wall thickness in other parts of the bend of the back; The nozzle and the pipe body wall thickness. Specified in the relevant national standards. Check for such problems, using measuring tools such as caliper, often difficult to find, at this time only can be measured using ultrasonic thickness gauge.
Second, the hardness of paint
Butt welding elbow hardness of overweight problems, mainly due to the heat treatment after forming process The solution is to use the correct heat treatment process for an additional heat treatment.
Three, produced by the defects in materials and processing
The defect of butt welding elbow harm the safety of the plant is the largest. Check up and more troublesome. Factors of defects are more complex, more it is a combination of material itself defects and processing manufacturing process and heat treatment process of defects caused by the incorrect.
Source: Yaang Pipe Industry Co., Limited (www.yaang.com)