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What Should We Pay Attention to when Welding Stainless Steel Pipe Fittings?

Mar. 04, 2020

1. In order to prevent corrosion between the eyes due to heating, the welding current should not be too large, 20% less than carbon steel electrodes, the arc should not be too long, and the interlayer should be cooled quickly.

2. The stainless steel pipe is harder after welding, which facilitates cracks. If welding with a typical stainless steel pipe is accepted, it must be preheated above 300 ℃ and slowly cooled at 700 ℃ after welding. If the weldment cannot be heat-treated after welding, stainless steel pipe electrode should be used.

3. For stainless steel pipe fittings, appropriate amounts of invariant elements Ti, Nb, Mo, etc. are appropriately added to improve the corrosion resistance and weldability. The weldability is better than stainless steel pipe fittings. When accepting the same typical chromium stainless steel electrode, it should be preheated above 200 ℃ and tempered at 800 ℃ after welding. If the weldment cannot be thermally treated, a chromium-nickel stainless steel electrode should be used.

What Should We Pay Attention to when Welding Stainless Steel Pipe Fittings?cid=3

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4. Stainless steel pipe fittings china welding rod has exquisite corrosion resistance and oxidation resistance, and is widely used in chemical, fertilizer, petroleum, and medical machinery manufacturing.

5. Stainless steel pipe covers have titanium calcium type and low hydrogen type. Titanium-calcium type can be used for AC and DC, but the welding depth is shallow during AC welding, and it is convenient for redness.

6. Stainless steel pipe has certain corrosion resistance (oxidizing acid, organic acid, cavitation), heat resistance and wear resistance. All materials used in power station, chemical industry, petroleum, etc. The weldability of stainless steel pipe fittings is poor. We should pay attention to the welding process and talk about the selection of suitable welding electrodes before heat treatment.

7. The electrode should be connected and dried during the operation of the electrode. The titanium-calcium type should be dried at 150 ° C for 1 hour, and the low-hydrogen type should be dried at 200-250 ° C for 1 hour. Coating oil and other dirt, so as not to increase the carbon content of the weld and affect the quality of the weldment.

8. During welding of stainless steel pipe fittings, carbides are repeatedly heated to precipitate carbides, reducing corrosion resistance and mechanical performance.

Introduction to common problems of sanitary stainless steel pipe fittings, there are many types of sanitary stainless steel pipe fittings, including sanitary tees, sanitary elbows, sanitary clamps, etc., because they have certain advantages in the field of environmental protection and sanitation, so in these areas Is widely used, especially in flammable and explosive pipelines. However, there are also some problems with the quality of stainless steel pipe fittings. Let ’s take a look together.

Stainless Steel Elbow 90° supplier introduces common problems for you

1. Uneven wall thickness of sanitary stainless steel pipe fittings

The uneven wall thickness of sanitary stainless steel pipe fittings mainly occurs in the parts where the stainless steel pipe is most deformed, such as the wall thickness at the back of the elbow is thinner than other parts; In order to check out these problems, calipers and other commonly used measuring tools are not easy to detect. At this time, only an ultrasonic thickness gauge can be used to detect them.

2.Excessive hardness

The problem of excessive hardness is mainly due to the heat treatment process after forming. The solution is to use the correct heat treatment process for another heat treatment.

3. Inspection of stainless steel pipe fittings before delivery and after delivery

As the last process to ensure the quality of sanitary stainless steel pipe fittings, inspection plays an important role, especially for stainless steel pipe fittings that withstand high temperatures and pressures and flammable and highly toxic media.