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What Is The Slip On Flange

Apr 25, 2020

        Slip on Flange, also called SO flange. It’s a kind of flange slides over the pipe with internal design is slightly larger than the pipe. Since the inner diameter of the flange is slightly larger than the outer diameter of the pipe, the SO flange can be directly connected to equipment or pipe by fillet weld at the top and bottom of the flange. It is used to insert the pipe into the inner hole of the flange.

Advantages and disadvantages of Slip-on Flange.

       Advantages: Slip on Flanges or SO flanges are commonly lower in price than weld-neck flanges, and to this effect are a popular choice for our customers. However, customers should bear in mind that this initial cost saving may be diminished by the additional cost of the two fillet welds required for proper installation. Moreover, weld-neck flanges have a higher life expectancy than Slip on Flange under duress.

        Disadvantages :The calculated strength from a Slip on Flange under internal pressure is of the order of two-thirds that of Welding Neck flanges, and their life under fatigue is about one-third that of the latter.

        This space is necessary, to do not damage the flange face, during the welding process.A disadvantage of the flange is, that principle always firstly a pipe must be welded and then just a fitting. A combination of flange and elbow or flange and tee is not possible, because named fittings have not a straight end, that complete slid in the Slip on Flange.


Standard – ANSI/ASME : ANSI B16.5, ANSI B16.47, MSS SP44, ANSI B16.36, ANSI B16.48

DIN : DIN2527, DIN2566, DIN2573, DIN2576, DIN2641, DIN2642, DIN2655, DIN2656, DIN2627, DIN2628,DIN2629, DIN 2631, DIN2632, DIN2633, DIN2634, DIN2635, DIN2636, DIN2637, DIN2638, DIN2673

B.S: BS4504, BS4504, BS1560, BS10

Size: 1/2″ (15 NB) to 48″ (1200NB)

Class: 150 LBS, 300 LBS, 600 LBS, 900 LBS, 1500 LBS, 2500 LBS, DIN Standard ND-6,10, 16, 25, 40 Etc.

Specialize :As per drawing


Stainless Steel Slip on Flanges : ASTM A182, A240F 304, 304L, 304H, 316, 316L, 316Ti, 310, 310S, 321,321H, 317, 347, 347H, 904L

Carbon Steel Slip on Flanges : ASTM 1 ASME A/SA 105 ASTM1 ASME A350 , ASTMA181LF 21 A516 Gr.70 iA36, A694 F42, F46, F52, F60, F65, F70

Alloy Steel Slip on Flanges : ASTM 1 ASME A/SA 182 &A387F1,F5, F9, F11, F12, F22, F91

Duplex Steel Slip on Flanges : ASTM 1 ASME A/SA 182F44, F 45, F51,F53,F55,F60,F61

Super Duplex Slip on Flanges : ASTM 1 ASME A/SA 182, A240F 44, F 45,F51,F 53,F 55,F60, F 61

Nickel Alloy Slip on Flanges :Nickel 200 (UNS No. N02200), Nickel 201 (UNS No. N02201), Monel 400(UNS No. N04400), Monel 500 (UNS No. N05500), Inconel 800 (UNS No. N08800), Inconel 825 (UNS No.N08825), Inconel 600 (UNS No. N06600), Inconel 625 (UNS No. N06625), Inconel 601 (UNS No. N06601),Hastelloy C 276 (UNS No. N10276), Alloy 20 (UNS No. N08020), Titanium (Grade I& l)

Copper Alloy Slip On Flanges : UNS No. C10100, 10200, 10300, 10800, 12000, 12200, 70600, 71500, UNSNo. C 70600 (Cu -Ni- 90/10), C 71500 (Cu-Ni-70/30)

Low Temperature Carbon Steel Slip on Flanges : ASTM A350, LF2, LF3