SU1551919A1 - Stuffing box seal - Google Patents

Abstract

The invention relates to a sealing technique, mainly to movable pressure seals of rods and shafts with valve and cylinder bodies. The purpose of the invention is to increase the reliability and reduce the axial dimension. The yoke encompassing the gasket is made in the form of a rolling membrane pressed against the outer portion to the cell body. The rolling membrane is made of a plastic material, for example soft steel. The main effect is a multiple increase in reliability due to a decrease in sensitivity to radial displacement of the shaft and automatic self-pressing of the packing under the action of the pressure of the medium and after its decrease. 2 hp f-ly. 1 il.

Description

This invention relates to a sealing technique.

The purpose of the invention is to improve the reliability and reduce the axial dimensions of the stuffing box.

The drawing shows the design of the packing seal (SU)

The gland seal of the movable shaft (stem) 1 with the housing 2 contains a ferrule 4 arranged in a bore 3 of the housing 2 in the form of a rolling membrane with a corrugation 5, pressed along the outer section 6 to the body 2 by a pressure element 7. Inside the ferrule is a membrane 1 s 4 its inner end accommodates a pressure sleeve 8 and a gasket 9. The dotted line shows the position of the rolling membrane when the gasket is fully worn. The arrow P indicates the direction of the pressure of the medium. The axial dimension L of the seal is determined by the length I of the packing and the stroke h of the end of the corrugation 5 in the process of compensating for the maximum wear of the packing. Considering that in this case the free end moves by a length 1 greater than the stroke h of the corrugation face, the value h is less than 1, which leads to a reduction in the axial dimension of L. The gap b between the membrane 4 and the bore of the housing 3 is greater than the possible radial displacement of the shaft in the housing. The amount of initial compression of the packing during assembly is automatically limited by the force required to roll the membrane in the absence of an abutment of its free end into the end of the body, which further increases the reliability of the device.

Gland seal works as follows.

The medium with pressure P acts on the gasket 9 and the membrane 4, trying to displace its corrugation and the free end outside of the SU. Resting against the packing, the free end of the membrane creates an additional pressing in it that provides a self-sealing effect similar to the differential seals. The radial mixes of the shaft practically do not change the set

ABOUT

3

the press of the packing, as it is displaced together with the pressure sleeve and the diaphragm following the shaft due to the low stiffness of the corrugation of the membrane.

Claims (3)

Claim 1. Gland sealing of a movable shaft-housing connection comprising a ferrule with a gasket and a pressure sleeve placed in a bore of the housing, and a gland element characterized in that, in order to increase reliability and reduce the axial dimension, the ferrule is made in the form of a rolling membrane pressed against outer section to the body In the case of the manufacture of a membrane made of plastic material, the axial displacement of its free end with additional pressing of the packing as a result of the pressure of the medium is maintained even after reduction pressure medium. Thanks to this effect, the gland packing "The shape fixing pad is automatically and the push sleeve is located between with each cycle, a higher internal region of the membrane and pressure of the medium P is pressed and retained by this element, and between the pressing elecfogzh after the decrease of P, a cavity is formed by the provisional membrane and Ensures SU high reliability and length -15 for rolling the cage as wear a service life without maintenance, i.e. packing stuffing, and the internal without the usual regular nut tightening. The membrane section is located on the side high pressure. Reducing the axial dimension of the SU 2. The seal according to claim. 1, characterized by due to the inherent rolling meme that the rolling membrane is punctured by the property of a plastic material reduced by a factor of two to 20 yen, times the movement of the end of the corrugation compared to 3. The seal according to claim 2, characterized by moving it loose, so that soft steel is used as a ductile plastic material. Claim 1. Gland sealing of a movable shaft-housing connection comprising a ferrule with a gasket and a pressure sleeve placed in a bore of the housing, and a gland element characterized in that, in order to increase reliability and reduce the axial dimension, the ferrule is made in the form of a rolling membrane pressed against outer section to the body element, with the stuffing box m g S