Lap joint flange stub end

Sometimes we call lap joint flange as loose flange which used in conjunction with a “Lap Joint Stub End”.Their dimension is same as other flanges.

They are widely used in oil field, offshore, water system,shipbuilding,natural gas,electric power,and pipe projects.

Lap joint flange or loose flange finished in Haihao Group

Lap joint flange or loose flange finished in Haihao Group

Flange specification:

Material: Carbon steel: A105, SS400, SF440 RST37.2, S235JRG2, P250GH, C22.8, Stainless Steel: F304 F304L F316 F316L 316Ti

Standard: ANSI, JIS, DIN, BS4504, SABS1123, EN1092-1, UNI,AS2129, GOST-12820

Size: 1/2-78 inch (DN15-DN2000)

Pressure: ANSI class 150, 300, 600, 1500, 2500, DIN PN6, PN10, PN16, PN25, PN40, PN64, PN100, PN160

Packing: No Fumigate or Fumigate Plywood/Wood Pallet or Case

Surface Treatment: Anti-rust Oil, Transparent/Yellow/Black Anti-rust Paint, Zinc,Hot dipped Galvanized.

Lap joint flange(Loose flange) advantages:

Freedom to swivel around the pipe facilitates the lining up of opposing flange bolt holes.

Lack of contact with the fluid in the pipe often permits the use of inexpensive carbon steel flanges with corrosion resistant pipe.

In systems which erode or corrode quickly, the flanges may be salvaged for re-use.

What is Stub End?

Stub end is a type of steel butt welded pipe. It is a short piece of pipe with a narrow shoulder on the end. The other end is butt welded to a pipe, this end called hub. The shoulder is like a raised face of flange, the hub is a neck.

It has long and short types. ASME B16.9 stub ends have both long and short pattern, but MSS SP-43 stub end is available in short pattern only.