Under what circumstances should internal grooves be selected for welded butt joints? Under what circumstances should external bevel be chosen? Are there any standard regulations?

The choice of inner or outer groove depends on the specific engineering design requirements and application scenarios. Generally speaking, the following factors may influence the choice: 1. Pressure requirements: Internal bevels are often used in high-pressure or ultra-high-pressure piping systems because they provide better sealing performance. 2. Fluid properties: If the fluid has higher sealing requirements, or has higher corrosiveness, toxicity, etc., the inner groove can provide better protection. 3. Construction conditions: The outer groove is easier to construct than the inner groove, especially in on-site construction. If construction conditions limit the use of internal bevels, external bevels may be a more appropriate choice. In addition, the choice of inner groove or outer groove for welded butt joints may also be affected by * * or the impact of industry standards. Specific standards may have specific requirements and recommendations for different types of joints. Therefore, when welding butt joints, it is recommended to refer to relevant standard regulations to ensure compliance with safety and quality requirements. .

Generally speaking, according to the design and manufacturing process requirements.

This post was last edited by wanlirn on 2023-9-4 09:11 As a container designer, you should learn* Let’s talk about the manufacturing process of the equipment. For example, even a person with a diameter of 400 cannot drill in. It must be an outer groove, which is made by argon arc welding and welded on one side and formed on both sides. For example, if a weld with a diameter of 2000 requires root cleaning welding, you would not choose an outer groove, which would make root cleaning difficult. . . .

If the outer diameters of pipes and fittings are the same but the difference in wall thickness is too large, in order to ensure a smooth transition during welding and pass radiographic flaw detection, the inner grooves of the thicker pipes should be polished. Learn from each other’s personal opinions * .

The general choice is the outer groove, and rarely the inner groove. Because generally speaking, it is more comfortable to weld the outside than the inside, so most people choose the outer groove. People with small diameters who cannot go in and weld will choose the outer groove. If there are other special requirements, the design will also consider the internal bevel.

From a manufacturing perspective, the groove method determines the welding method to be used. For example, welders cannot enter pipes or cylinders below DN800, so they can only use external grooves. The barrels of large equipment generally have larger diameters and thicknesses, and submerged arc automatic welding is used more often. The head of the cross can extend into the barrel, and it is safer for welders to weld inside the barrel. The advantage of using an inner groove is that it is easier to clean the roots on the outside after the inside is welded than on the inside.

Look at the process, equipment size, media characteristics, manufacturing equipment, etc. To understand the characteristics and process requirements of production, this cannot be explained clearly in one or two sentences. You will know as it slowly settles. The 5th floor above is just in terms of size. In terms of manufacturing process, if there is no hole in the last closing seam, do you think it is an inner bevel or an outer bevel? Think to yourself.

The outer bevel has good construction conditions and the inner bevel has a good appearance. For thinner ones, use single-sided beveling, and for thicker ones, try to use double-sided beveling.