WPL6 elbow

WPL6 elbow introduction:

Steel grade: WPL6

Chemical composition,%

C: ≤ 0.30

Mn: 0.50-1.35

P: ≤ 0.035

S: ≤ 0.040

Si: 0.15-0.40

Ni: ≤ 0.40

Cr: ≤ 0.30

Mo: ≤ 0.12

Cu: ≤ 0.40

Cb: ≤ 0.02

heat treatment

All pipe fittings shall be supplied in the state of normalizing, normalizing plus tempering, annealing or quenching plus tempering. Welding shall be completed before austenitizing heat treatment

If specified in the order, the specimen can be subjected to simulated PWHT. Simulated PWHT temperature: 595 – 650 ° C. Small heat preservation time: 1h/25mm, not less than 45 minutes

WPL6 elbow is connected by carbon steel elbow, connecting two pipes with the same nominal diameter to make the pipe rotate at the viewing point. Raw materials include carbon steel, cast steel, alloy steel, stainless steel, copper, aluminum alloy, etc. Carbon steel elbow is a kind of pipe fitting commonly used in pipeline installation, which is used to connect the elbow of pipeline. Carbon steel elbow is favored by shopping malls and continues to replace some conservative anti-wear materials. The fundamental reason lies in its excellent product quality and conservative anti-wear materials. These steels have good wear resistance and toughness, simple production process, economic and correct, applicable to a variety of working conditions, welcomed by users, and not slow in manufacturing and application. This also makes the use of thick wall anti-wear elbow more and more common, and the cost is lower and lower

I. The preheating of WPL6 elbow helps to reduce the large hardness of medium carbon steel heat affected zone and prevent cold cracking. This is the main process measure for welding medium carbon steel. Preheating can also improve the plasticity of welded joints and reduce the residual stress after welding

II. Generally, when the preheating temperature of 35 and 45 steels is 150~250 ℃, due to the relationship between thickness and stiffness, if the carbon content is good or the crack tendency is large, the preheating temperature can be increased to 250~400 ℃

III. If the weldment is too large and the overall preheating is difficult, local preheating can be carried out. The heating range of local preheating on both sides of the weld is 150~200mm. When conditions permit, alkaline electricity should be used

IV. If stress relief heat treatment cannot be carried out after welding, post welding heat treatment shall be carried out immediately. In terms of design stress, carbon steel elbow has good compressibility

V. Due to the influence of various factors, the actual wall thickness of floor heating pipes is usually the same. Under this wall thickness, all kinds of pipes can meet the requirements of floor heating. Therefore, the pressure free advantage of national standard carbon steel elbow cannot meet the requirements of floor heating

VI. Pipes used for floor heating need good thermal conductivity, low temperature thermal shock resistance and low temperature impact resistance. OK.