How to detecting carbon steel elbow?
What are the common methods for detecting carbon steel elbows?
Carbon steel elbow inspection method. The carbon steel elbow is made of carbon steel as the main material, and it receives the response standard and state control during the actual welding construction. It can continue to develop and progress in the corresponding market scale. The knowledge benefits of carbon steel elbows are mainly reflected in the following aspects: 1) Pipe blanks can be saved without the need for billets as materials. The production cycle is shortened and the production cost is greatly reduced. Because it does not require special equipment, it is especially suitable for processing large curved pipes on site.
Carbon steel elbow detection component:
1. Carbon steel elbow appearance inspection, generally based on the naked eye observation, sometimes observed with a 5-20 times magnifying glass. After visual inspection, it was found that there were undercuts, welds, surface cracks, pores, slag inclusions, penetration and other defects on the surface of the welded elbow. Weld size can also be measured with a weld detector or template.
2. Non-destructive testing of carbon steel elbows to detect defects such as slag inclusions, pores and cracks in the weld. At present, X-ray inspection, ultrasonic flaw detection, magnetic flaw detection, etc. have been widely used. X-ray inspection uses X-ray to photograph the weld, and judges whether there are internal defects, the number and type of defects based on the negative image. The weld is then evaluated according to the technical requirements of the product. The basic principle of ultrasonic flaw detection is shown in the figure below.
The ultrasonic beam is emitted from the probe and transmitted to the metal. When the ultrasonic beam is transmitted to the interface between the metal and the air, it refracts and passes through the weld. If the weld is defective, the ultrasonic beam will be reflected onto the probe and accepted, and the reflected wave will appear on the screen. The size and location of the defect can be determined by comparing and identifying these reflected waves and normal waves. Ultrasonic flaw detection is much simpler than X-ray photography and is therefore widely used. However, ultrasonic flaw detection can only be judged by operational experience, and the test basis cannot be left. For internal defects and surface microcracks that are not deeper than the surface of the weld, magnetic flaw detection can also be used.