Flanges flat steel the present standard extends to flanges steel flat welded pipelines and connecting parts, and also to connecting flanges of fittings, connecting parts of cars, devices, branch pipes, devices and tanks.
Technical characteristics of flanges:
Flanges have to be produced with sealing surfaces of executions 1., 2., 3, and connecting sizes in accordance with GOST 12815-80. Production of flanges with sealing surfaces of executions 4 is allowed., 5., 8. and 9. An identification number at the order of a round steel flat welded flange of Dy of 50 mm for Py of 1.0 MPAS (10 kgfs/cm2) from steel 25, execution 1 (with a connecting ledge):
Maximum deviations of the sizes: Dn-on H 14 (when receiving by stamping - on class state standard specification 7505-98) Yu and also produced by method are flexible b-for stamped flanges from strip hire with the subsequent welding of a joint and is hotter a rikhtovka - on GOST 7505-89 T4 accuracy class. At the same time strengthening of a seam which when determining maximum deviation is not considered Flanges flat steel GOST 12822-80 is allowed
The present standard extends to steel flanges of pipelines and connecting parts of cars, branch pipes of devices and tanks, free on a welded ring, on Py from 0.1 to 2.5 MPas (from 1 to 25 kgfs/cm2) and temperature of Wednesday from 243 to 573 To (from minus 30 to plus 300 C).
Rings have to be produced with sealing surfaces of executions 1., 2., 3 and connecting sizes in accordance with GOST 12815-80. Production of rings with sealing surfaces of executions 4, 5, 8 and 9 is where technically justified allowed.
One of basic elements of the pipeline are flanges which provide reliable tightness of the connected sites or shutoff valves, and, in too time, allow to perform repair work quickly.
Flanges vorotnikovy are connecting elements in the form of a disk with "collar" with the openings necessary for fixture located on them. Fastening is made by means of bolts and hairpins, hermetically connecting pipes with pipeline fittings.
Flanges are applied to connection of shutoff valves with pipelines, installation of separate sites of pipelines, and also to connection of pipelines to various (for example, boiler) to the equipment.
The advantage of flange collars is connections ensuring durability and tightness of a design is. Besides, flanges are simple in production, allow to carry out fast installation and dismantle of shutoff valves and sites of pipelines.
Flanges are divided by constructive characteristics on flat, vorotnikovy and carving. The greatest distribution was gained by flanges vorotnikovy which distinctive feature is that they are welded on a pipe end-to-end. So, the internal diameter of vorotnikovy flanges is equal to the internal diameter of a pipe.
Flanges intend for tight connection of communication pipes, and also for accession them to machines, devices and capacities, for connection of shaft, etc. the rotating details.
Flanges can differ by the sizes, a form of a sealing surface and a way of fastening. The flange is an independent detail, but more often he can be met as an element of a pipe, a shaft or a fitting.