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1. Nominal diameter of a shaft

A shaft should be made with the dimensional deviations H 11, of hardened steel, surface roughness defined by the table I, compatible with PN-73/M-04251, and the lay defined by PN-74/M-01146.

Table l

District speed m/s

The parameter of roughness Ra

1

2

up to 1 over 1.1 up to 8 over 8

1.25 1,00 up to 0,63 0,5 up to 0,32


Vitality of space you are sealing depends on hardness of shaft's surface near by working seal ring. That hardness should be not less than 45 HRC. In case of impurity from the outside, as well if tangential velocity is over 4 m/s, the hardness of shaft's surface should be not less than 55 HRC. Whereas the surface is being hardened, depth of the hardening layer should be not less than 0,3 mm.

2. Diameter of a casing

Diameter of a socket, where a ring will be installed to seal a shaft, should be made and worked according to PN-73/M-04251 / the dimensional deviations H 11 /. A socket ought to assure, that a ring will be coaxial embedded, perpendicularly to shaft's axle. It is necessary to avoid one-sided load to seal lip and axial run-out. Deviations of exterior diameter of a ring are presented in the table 2.

Table 2

Exterior diameter of a ring

Dimensional deviations

Admissible oval

Mm

over

up to

+0,4 +0,2

0,3

 

50

50

80

+0,2 +0,4

0,4

80

120

+0,2 +0,4

0,5

120

180

+0,2 +0,5

0.6

180

300

+0,3 +0,7

0,8

300

500

+0,3 +0,8

1,0

3. Height of a ring.

There are heights of seal rings (h) given in fourth column. Deviations of rings' heights are presented in the table 3.

Table 3

Heights of rings h

Deviations

Mm

over

up to

+0.3 -0,2

7

10

10

15

+0,4 -0,3

15

30

+0,6 -0,3

     

4. Other notes

Mounting seal rings you should pay your attention to switch seal's lip inside space that you are sealing.

Seal rings should be built upon coaxially and perpendicularly to shaft's axle in plane. Seal rings are not able to transfer lengthwise or lateral stress. Mounting seal ring, cram it, pushing uniformly. A spring should be installed to have a tendency to press seal's lip to a shaft.

Seal ring, correctly crammed to socket, should be leant its face against socket's wall or stopper ring, on the whole surface. A shaft, near by working seal ring, should be oiled.