Slipsfläns

Slipsfläns, referred to in English as slip-on flanges, are a type of pipe flange designed to slip over the end of a pipe before being welded in place. The flange has a bore that is slightly larger than the pipe diameter, which allows it to be positioned over the pipe and aligned with a mating flange for bolted connection and gasket sealing.

Construction and installation are characteristic of slip-on flanges. They are produced with a hub that slides over the pipe, and once aligned, the flange is tack-welded to hold it in place. Final strength is achieved by welding around the exterior and, in some designs, also the interior fillet. The bolted connection between two flanges, with a gasket in between, provides the seal. Slip-on flanges are available in standard face types, such as raised-face or flat-face, and can be finished to match common mating flanges.

Materials, sizes, and standards vary. They are commonly manufactured in carbon steel, stainless steel, and alloy steels, covering a wide range of nominal diameters and wall thicknesses. Typical pressure ratings for slip-on flanges range from low to moderate, often found in classes such as 150 and 300, with higher ratings possible for specific materials and sizes. Standards for dimensions and tolerances include variations of ASME B16.5 and international equivalents (for example, DIN EN 1092-1), with the flange faces designed to accommodate standard gaskets.

Applications and considerations. Slip-on flanges are favored for lower-cost, easier alignment, and simpler fabrication, making them popular in low- to moderate-pressure piping systems in chemical, petrochemical, water, and general industrial service. They are generally weaker than weld-neck flanges under high loading or high-temperature conditions due to the fillet welds and hub design, which is a consideration in flange selection.