Stainless steel Pipe cap, also known as plug or head, is a pipe fitting that is welded on the pipe end or installed on the external thread of the pipe end to cover the pipe. Used to close the pipeline, the function is the same as the plug.

Stainless steel Pipe cap includes the design of convex pipe cap, cone shell, variable diameter section, flat cover and tightening mouth.

Convex stainless steel pipe caps include: hemispherical pipe caps, oval pipe caps, dish-shaped pipe caps and spherical caps. From the force point of view, the hemispherical tube cap is gradually not good for the convex tube cap, but from the perspective of manufacturing difficulty, it is gradually easier to manufacture. Avoid splicing at the joints of the dish-shaped stainless steel pipe cap, which will cause thinning and high stress.

When splicing, the direction of the welding seam is only allowed to be radial and circumferential. In the future, large stainless steel pipe caps may cancel this requirement. The splicing distance should be required, and not less than 100mm. The welding heat-affected zone is a high-stress zone, and the chemical composition in this zone will be damaged. So avoid the high stress area, which is related to the thickness. According to practical experience, the stress attenuation length is greater than 3δ and not less than 100mm. However, refrigeration equipment is difficult to meet this requirement and has its particularity.

For the stainless steel pipe cap formed after splicing, the splicing welds should be subjected to 100% radiographic or ultrasonic testing, and the qualification level follows the equipment shell. The final weld seam detection level and ratio are the same as the equipment shell.