Your contact for lens seals

Your contact for lens seals

Lens seals are re-usable several times

Lens seals

Lens seals are reusable, as the sealing effect is generally achieved by elastic deformation of the surfaces. The projected sealing width bG is calculated in relation to the angle a, which forms the sealing surface against the direction of the force (tubular axis) depending on the E modulus EG and the surface pressure exerted by bG = 100 • σ / EG • r • sinα.

Gasket profiles

Lens seals are impervious to overpressure. Within creasing loads, the contact surface between the sphericallens surface and thespherical flange groove increases, so that the surface pressure only increases to a lesser extent.

A disadvantage with standard sealing lenses is that, at high pressures and temperatures, the sealing lens can bulge along the circumference and weaken the tension of the connection. Also, at greater nominal diameter, the flange can become stuck in the area of the raised face diameter d5 and lift up at the sealing diameter.

We can also specially produce bellows lenses, lens blind spectacle gaskets and half-lenses. Lens blind spectacle gaskets are made of a sealing lens and a lens blind, which are connected by a ligament. It is also usual to use lens blinds on their own. In this case, it is useful to weld on a small plate to render the lens blind distinguishable.

 

Steel type designationMaterialnumberfor circulatory temperaturesCode designationon the outer edge
S235JRG21.0038to 425°Cnone
P265GH1.0425to 425°Cnone
16Mo31.5415425 to 4751 Ankörnung
13CrMo4-51.7335425 to 5202 Ankörnungen
10CrMo9-101.7380520 to 5803 Ankörnungen
X6CrNiTi18-101.4541350 to 5504 Ankörnungen
12CrMo19-51.7362Max 650°C1 Kerbe
X6CrNiMoTi17-12-21.4571Max 550°C3 Kerben

Gasket limiting values

ProfileA5, A5S, A5BS
MaterialIron 1.100 Stw24moddHeat-resistant mild steel 1.5415Heat-resistant mild steel 1.7362Stainless Steel 1.4541Stainless Steel 1.4828Steel ST 35 cooper-platedSteel 1.4541 silver-platedCooper 2.0090Monel 2.4360
Recommended max. roughness of the flange surfacesµmfrom
to
3,2
6,3
3,2
6,3
3,2
6,3
1,6
3,2
1,6
3,2
3,2
6,3
6,3
12,5
3,2
6,3
3,2
6,3
Surface pressure limits for 20 °CN/mm2σv
σϑ
235
525
300
675
400
900
335
750
400
900
135
600
100
750
135
300
260
660
E modulus at 20 °CkN/mm2 210210210200200210200128178
Surface pressure limits for 300 °CN/mmσv
σϑ
235
315
300
585
400
730
335
630
400
750
135
390
100
630
135
150
260
650
E modulus at 300 °CkN/mm2 185185190186186185186114175