Hastelly Socket Weld flanges were initially developed for use on small-size high pressure piping. Their static strength is equal to Slip On flanges, but their fatigue strength 50% greater than double-welded Slip On flanges. The connection with the pipe is done with 1 fillet weld, at the outside of the flange. But before welding, a space must be created between flange or fitting and pipe.
The purpose for the bottoming clearance in a Socket Weld is usually to reduce the residual stress at the root of the weld that could occur during solidification of the weld metal. The image shows you the X measure for the expansion gap.
The disadvantage of this flange is right the gap, that must be made. By corrosive products, and mainly in stainless steel pipe systems, the crack between pipe and flange can give corrosion problems. In some processes this flange is also not allowed. Also for this flange counts, that principle always firstly a pipe must be welded and then just a fitting.
Hastelly Socket weld pipe flanges are used in the applications where there are smaller sizes of high pressure pipes used. These pipe flanges are attached by inserting the pipe into the socket end and applying fillet weld around the top. This helps in better flowing of the fluid or gas inside the pipe. These socket weld pipe flange is available in all materials, sizes and specifications.
Grade: Hastalloy B2, Hastalloy B3, Hastalloy C22, Hastalloy C276, Hastalloy X
|Hastelloy B||0.1||1.25||0.6||28||0.3||-||-||-||-||-||5.5||rest/bal||Mn 0.80; Si 0.70|
|Hastelloy B2||0.02||1||1||26.0-30.0||-||-||-||-||-||-||2||rest/bal||Mn 1.0, Si 0.10|
|Hastelloy X||0.1||1.5||22||9||-||0.6||-||-||-||18.5||-||rest/bal||Mn 0.6; Si 0.60|
|Grade||Tensile (ksi)||.2% Yield (ksi)||Elongation %||Hardness (HRb)|
Stainless Steel :
Grade: 304 (1.4301), 304L (1.4307), 304H (1.4948), 309 (1.4828), 309S, 310, 310S (1.4845) , 316 ( 1.4401), 316H, 316L( 1.4404 /1.4432) , 317, 317L (1.4438), 321 (1.4541), 321 H(1.4878), 347 (1.4550), 347H (1.4961), 904L (1.4539)
Grade: 2205 (1.4507)
Super Duplex Steel:
Grade: 2507 (UNS S32750) (1.4410) (UNS S32750)
Grade: Inconel 600 (2.4640), Inconel 601 (2.4851), Inconel 625 (2.4856), Inconel 718(2.4668)
Grade: Incoloy 800 (2.4958), Incoloy 800H, Incoloy 800HT
Grade: Nickel 200, Nickel 201
Grade: Monel 400 ( 2.4360), Monel K500, Monel R-405
Grade: Gr.1 (3.7025) , Gr.2 (3.7035) , Gr.3:(3.7055) , Gr.5(3.7164/65), Gr. 7(3.7235) , Gr. 11 (3.7225)
The manufacturing process of flange mainly is divided into forging, casting, cutting and rolling. .
The casting and forging flanges have advantages that the blanks of them have accurate shape, size and low costs and only need simple process. But forging flanges have manufacturing defects such as blowholes, cracks, etc and have not very smooth internal organization streamline. The obvious advantages of forging flanges are that they can be forged in various shapes and they have low costs. .
Forging flanges generally have lower carbon content than the casting flanges and are not easy to rust. They have smooth streamline, uniform internal organization, and better mechanical performance than that of casting flanges. There are no defects, such as blowholes and cracks existing in the casting flanges. Forging flanges are able to withstand higher shear and drawing forces than casting flanges. However, if adopting improper forging process, it will also cause appearance of large, uneven grains and solidification cracking phenomenon, resulting in higher cost than the casting flanges. .
We can distinguish between the casting flanges and forging flanges from the different production process. To take the centrifugal flange as an example, it is a kind of casting flange. Centrifugal flanges are produced by a precision casting method, which makes the flanges’ organization smaller than those commonly produced by sand casting and improves the quality of flanges, making fewer occurrences of loose tissue, pore, sand hole etc.
Cutting process refers to producing flanges by directly cutting a round plate with the inner diameter, outer diameter and thickness which can be further processed later from the middle plate, and then processing the bolt hole and waterline. The maximum diameter of such flanges is limited by the width of the middle plate.
Cutting process refers to producing flanges by cutting stripes from the middle plate and then rolling them into round shape. This process is mainly used for the production of large flange. After the rolling process, weld and then flatten the round shape, and finally process the serrated spiral finish and bolt hole.