RU204982U1 - FLAT CONNECTOR SEAL FIXED TOGETHER BODY PARTS TO FORM A SEALING CAVITY - Google Patents

Abstract

The utility model relates to flat joint seals of body parts fastened together, forming a sealing cavity. Seal of a flat connector of the body parts fastened together, forming a sealed cavity containing a groove with a curved contour in projection onto the parting plane, made on one of the parts, in which a sealing element made of an elastic elastic non-metallic material is located, the part protruding from the groove is compressed by the flat surface of the second part of the housing, with a chamfer made on one of the side walls of the groove along its entire length, and the material of the squeezed sealing element is placed between the groove chamfer and the flat surface of the second part of the housing. The sealing element is made of rubber, the sealing element is made in the form of a ring with a circular cross-section. The sealing element is made in the form of a cord with a round cross-section. The chamfer is made at an angle of 20 ° ... 45 ° to the parting plane. The invention provides for the elimination of the flow of the working medium from one cavity into another cavity or the surrounding space and an increase in the efficiency of the pump. 4 c.p. f-ly, 3 dwg

Description

The utility model relates to flat-split seals of body parts fastened together, forming a sealing cavity, such as, for example, the lower part of the pump casing and the cover of a centrifugal pump with a casing having a horizontal flat-split in a plane parallel to the shaft axis and can be used to create casing seals in centrifugal main oil pumps and other machines.

It is known to seal the flat joint of the body parts (lower and upper parts) of a centrifugal pump fastened together, in the inner cavity of which there is a centrifugal wheel with a double-sided entry and a shaft. At the same time, grooves with a curved contour in projection onto the plane of the part are made in the lower part of the housing on a flat surface, which envelop the channels for withdrawing the liquid from the pump and prevent the liquid from flowing into the channels for supplying the liquid to the pump wheel. In these grooves are placed rubber cords of a circular cross-section, and the part of the cord protruding from the grooves is compressed by the flat surface of the upper part of the body (see, for example, utility model patent No. 187032, F04D 29/68).

A feature of the known technical solution is that the curvilinear contour of the groove differs from the circle, which does not allow making the groove on a lathe - and the groove can only be made on a milling machine (with numerical control or another milling machine). In addition, the groove has a flat bottom and vertical walls, so the contact of the sealing element occurs with the flat bottom of the groove 19 and the flat surface of the upper part 5 of the body. This feature does not ensure the absence of liquid overflow between the semi-spiral outlet channel 9 and located on both sides of it - into the semi-spiral inlet channels 10 and 11 with a significant pressure difference in channels 9, 10, 11 - for example, with a difference of 20 ... 40 kgf / cm ² and more.

This is a disadvantage of the known seal, which reduces the efficiency of the pump due to the flow of liquid from the outlet channel 9 back to the channels 10 and 11.

The purpose of the utility model is to eliminate the drawback of the known technical solution.

This goal is achieved by the fact that the seal flat connector of the body parts fastened together, forming a sealing cavity containing a groove with a curved contour in projection onto the parting plane, made on one of the parts, in which a sealing element made of an elastic elastic non-metallic material is located, the part protruding from the groove is compressed by the flat surface of the second body part , in this case, a chamfer is made on one of the side walls of the groove along its entire length, and the material of the squeezed sealing element is placed between the groove chamfer and the flat surface of the second part of the body. In this case, the sealing element can be made of rubber in the form of a ring with a circular cross-section or in the form of a cord with a circular cross-section. The chamfer is made at an angle of 20 ° ... 45 ° to the parting plane.

FIG. 1 shows a section A-A of the proposed seal, FIG. 2 is a plan view of a part of a housing with a groove having an elliptical contour in plan; FIG. 3 is a view of a part of the casing with a groove in relation to the casing of a centrifugal pump with a double-sided inlet, where:

1, 2 - body parts

3, 4 - flat surfaces

5 - hairpins

6 - nuts

7 - groove

8 - chamfer

9 - sealing element

10 - ring

11 - cord

12 - end of the cord

13 - ring

14 - projections

15 - groove

P ₁ , P ₂ - cavities

α is the angle.

The flat connector seal contains a lower part 1 and an upper part 2 of the body, which are made with flat surfaces 3 and 4 and are fastened to each other using threaded products, which are pins 5 screwed into part 1 and nuts 6 screwed onto them.

Bonded together, parts 1 and 2 form a sealed cavity "P ₁ " with a relatively high pressure (for example, 20 ... 40 kgf / cm ² ). On the surface 3 of the lower part, a groove 7 is made, for example, of a rectangular cross-section, a chamfer 8 is made on the edge of the groove along the entire contour (length). The groove contains a sealing element 9 of a circular cross-section made of a non-metallic elastic-plastic material, for example, rubber. Although it is possible to use other materials with elasticity and plasticity. The sealing element can be made in the form of a ring 10 (see Fig. 2) for the case when the groove is made with an elliptical curved contour, but not round, or round (a groove with a circular contour is not shown). If the sealing member is formed in an open-loop groove as shown in FIG. 3 for the case with the seal of the connector of the casing of a centrifugal pump for pumping oil - then in this case the element 9 is made in the form of a cord 11 made of an elastically elastic material. The ends 12 of the cord abut against the ring 13 installed between parts 1 and 2 of the body. So that the end 12 does not move inward along the groove (does not wrinkle) on the cord, in one piece with it, protrusions 14 are made, located in the grooves 15 communicated with the groove 7.

The angle "α" of the slope of the chamfer should be within 20 ° ... 45 ° depending on the pressure difference between the cavities P ₁ and P ₂ and this angle is selected experimentally, taking into account the dimensions of the groove 7. The dimensions of the groove and the thickness are selected in the same way ( diameter) of the sealing element (ring or cord).

The chamfer is performed on the groove wall that faces the cavity with a lower pressure, for example, from the side of the cavity P ₂ or from the external environment (see Fig. 1).

When the seal is operating, for example, as part of a pump, the pressure, which in cavity P _{1 is} higher than in cavity P _{2, the} sealing element 9 is pressed into the wedge space between the chamfer 8 and the flat surface 4 of part 2 of the body, preventing liquid flow from cavity P ₁ to cavity P ₂ , moreover, the greater the pressure difference, the stronger the indentation occurs (pressing of the element 9 to the surface of the chamfer 8 and flat surface 4, the stronger the specific pressure at the points of contact with the chamfer and flat surface, the more noticeable the effect of compaction.

This advantage of the proposed technical solution makes it possible to expand the scope of the seal using rings or cords with a circular cross-section due to the fact that the sealing element located in the wedge space between the chamfer in one part and a flat surface in another part will exclude the flow of the working medium from one cavity into another cavity (or surrounding space) with a greater pressure difference between the cavities than in the known technical solution.

Claims (5)

1. Seal of a flat connector of the body parts fastened together, forming a sealed cavity containing a groove with a curved contour in projection onto the parting plane, made on one of the parts, in which a sealing element made of an elastic elastic non-metallic material is placed, the part of which protruding from the groove is compressed by a flat surface the second part of the housing, characterized in that a chamfer is made on one of the side walls of the groove along its entire length, and the material of the squeezed sealing element is placed between the chamfer of the groove and the flat surface of the second part of the housing. 2. A flat connector seal of the body parts fastened together, forming a cavity to be sealed according to claim 1, characterized in that the sealing element is made of rubber. 3. A flat connector seal of the body parts fastened together, forming a cavity to be sealed according to claim 1, characterized in that the sealing element is made in the form of a ring with a circular cross-section. 4. A flat connector seal of the body parts fastened together, forming a sealed cavity according to claim 1, characterized in that the sealing element is made in the form of a cord with a circular cross-section. 5. Seal flat connector fastened together parts of the body, forming a sealed cavity according to claim 1, characterized in that the chamfer is made at an angle of 20 ° ... 45 ° to the plane of the connector.

Images