Ring-Joints RTJ
Ring-joint gaskets are manufactured from a metallic material
The demands on the geometrical accuracy and the surface quality are therefore high. This concerns both the gasket and the sealing section of the flange.The necessary surface quality depends substantial on the
Brinell hardness of the gasket material. We have found that the relation RZ[mm] < 300/HB gives a useful estimation
A distinction is made between two kinds of ring-joint gaskets
and two different calculation methods can be derived
RTJ gaskets with a snuggle fitting radius a) The convex octagonal RTJ gaskets, profile AR 13, in
which the cambered cone case surfaces of the gasket
are pressed against the bevel cone case surfaces of the groove during fastening
The oval ring-joint gasket, our profile A11, in which the
ball sealing surfaces are pressed against the cone case
surfaces
At this types the projection of the sealing surface width bD
results from the angle a, which the sealing surface against
the force direction (pipe axis) forms as a function of the Emodulus
ED and the number of contacting surfaces n
bD = b1 + b2 = 100 • • r • n • sina.
Important: The surface pressure increase or decreases
sub proportional to a possible change of the
bolt force.
RTJ gaskets with flat sealing surfaces )
The octagonal RTJ gasket, our profiles A13 and A14, in
which the sealing surfaces are two cone case surfaces. The
projection in the direction of the bolting force
bD = b1 + b2
is to be set as the sealing surface width.
Important: The surface pressure increase or decreases
proportional to a possible change of the bolt
force.
The calculations according to the preliminary standard DIN
2505 with the gasket parameters k0 and k1, which represent
a fictive width, do not deal with the complicated conditions
in snuggle fitting gaskets.
The application limits of oval and octagonal ring-joint gaskets
can be calculated more accurately as a function of the
material, diameter, pressure and temperature among other
things in accordance with the publication entitled
"Optimisation of static gaskets", 3. edition, by Hans-Joachim
Tückmantel, published by Kempchen Publishing,
Oberhausen 1990, ISBN no. 3-88432-003-3. Here the
gasket parameters are replaced by the values sv and sJ as
well as by the previous stated sealing width bD.
Ring-joint gaskets according to API and ASME standards
are mainly used in the petrochemical industry and in
refineries as a reliable gasket for pipelines with products.
We are entitled to give our products the API stamp of quality
- thus guaranteeing compliance of the design with the latest
API standards.
Profile AR 13 with cambered flanks. The advantages when
using convex shaped RTJ gaskets are explained in detail
in the article entitled "The Latest on Ring-Joint Gaskets"
which you can request from us as a special publication.
Ring-joint gaskets can also be manufactured as a blind
profile A11S, A13S, etc. or as a spectacle-type blind profile
A11BS, A13BS, etc.
Disturbing turbulences and deposits are avoided by means
of the additional placement of a protector ring made of steel
our Profile F 22. In the case of small rim widths the
protective gaskets are symmetrical, with larger rim widths
they are unilaterally centred.
Soft-iron compensating caps, our profiles AK11, AK12,AK13, AK14, are supplied for damaged grooves.
For comprehensive calculations with regard to sealing
flanged connections our gasket calculation service is at
your disposal at a favourable price