Method for assembling gasket of pipe joint with metal gasket

Abstract

A gasket assembling method for a pipe joint with a metal gasket comprises the following steps that the metal gasket before bending is bent through a deformation tool upper die and a deformation tool lower die, the bent metal gasket is formed, and it needs to be guaranteed that the bent metal gasket can pass through the large thread diameter of the pipe joint; after the locking nut, the bent metal washer and the pipe joint are assembled, pre-pressing is conducted through a pre-pressing tool upper die and a pre-pressing tool lower die, the pre-pressed metal washer is obtained, and the inner diameter of the pre-pressed metal washer is smaller than the pitch diameter of a thread of the pipe joint; the pre-pressed metal gasket assembly is flattened through a flattening tool upper die and a flattening tool lower die, and then the flattened metal gasket is obtained; due to the fact that the flattening tool limits the inner diameter of the flattened metal washer to be close to the diameter of a tool withdrawal groove of the pipe joint, the outer diameter of the flattened metal washer is close to the diameter of the metal washer before bending. In the process of assembling the pipe joint with the metal washer, the inner diameter of the metal washer and the pipe joint can be well sealed.

Description

Technical Field

[0001] The invention relates to a gasket assembling method of a pipe joint with a metal gasket, belonging to the technical field of fasteners. Background Art

[0002] like Figure 1 As shown in the figure, the pipe joint with metal gasket obtains good sealing performance after the locking nut is twisted to push the metal gasket to squeeze the seal. However, the existing metal gasket assembly process has the following problems: 1. The gap between the inner diameter of the metal gasket and the pipe joint is too small and cannot be obtained by turning.

[0003] 2. The inner diameter of the metal washer is smaller than the middle diameter of the thread and cannot be directly screwed into the thread.

[0004] 3. The inner diameter of the metal washer is smaller than the blank diameter of the pipe joint before thread rolling, and the metal washer cannot be installed before thread processing.

[0005] This results in poor sealing performance of the pipe joint and the requirement that the gap between the inner diameter of the metal gasket and the diameter of the pipe joint backcut should not be too large. Summary of the invention

[0006] The invention aims to solve the technical problem of how to ensure good sealing performance of a pipe joint with a metal gasket during assembly while ensuring that the gap between the inner diameter of the metal gasket and the diameter of the pipe joint backing groove is not too large.

[0007] In order to solve the above technical problems, the present invention adopts the following technical solutions: A gasket assembly method for a pipe joint with a metal gasket comprises the following steps: Step 1: bend the metal gasket before bending through the upper die and the lower die of the deformation tooling to form a bent metal gasket. The bent metal gasket must be able to pass through the major diameter of the thread of the pipe joint; Step 2: After assembling the locking nut, the bent metal washer and the pipe joint, pre-press them with the upper die and the lower die of the pre-pressing tooling to obtain the pre-pressed metal washer, and the inner diameter of the pre-pressed metal washer is smaller than the middle diameter of the pipe joint thread; Step 3: Flatten the pre-pressed metal gasket assembly with the upper die and the lower die of the flattening tool to obtain a flattened metal gasket; due to the limitation of the flattening tool, the inner diameter of the flattened metal gasket is close to the diameter of the pipe joint's back cutter groove, and the outer diameter of the flattened metal gasket is close to the diameter of the metal gasket before bending.

[0008] The beneficial effects of adopting the above technical solution are: In the process of assembling the pipe joint with the metal gasket, the invention enables the inner diameter of the metal gasket and the pipe joint to obtain good sealing performance; at the same time, the requirement that the gap between the inner diameter of the metal gasket and the diameter of the undercut groove of the pipe joint is not easy to be too large is met. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figure 1 It is a schematic diagram of the structure of a pipe joint with a metal gasket.

[0010] In the figure: 1-pipe joint, 2-locking nut, 3-metal washer, 4-sealing ring.

[0011] Figure 2 This is a structural schematic diagram of the metal gasket bending process.

[0012] In the figure: 5-metal gasket before bending, 6-upper die of deformation tooling, 7-metal gasket after bending, 8-lower die of deformation tooling.

[0013] Figure 3 This is a structural schematic diagram of the metal gasket pre-pressing process.

[0014] In the figure: 7-the metal gasket after bending, 9-the upper die of the pre-pressing tooling, 10-the lower die of the pre-pressing tooling, 11-the metal gasket after pre-pressing.

[0015] Figure 4 This is a structural schematic diagram of the metal gasket flattening process.

[0016] In the figure: 11-pre-pressed metal gasket, 12-flattening tool upper die, 13-flattening tool lower die, 14-flattened metal gasket. DETAILED DESCRIPTION

[0017] In order to make the objectives, technical solutions and advantages of the present invention more clear, the present invention will be further described in detail below in conjunction with the accompanying drawings. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0018] A gasket assembly method for a pipe joint with a metal gasket comprises the following steps: Step 1: If Figure 2 As shown: the metal gasket 5 before bending is bent by the upper die 6 and the lower die 8 of the deforming tooling to form a bent metal gasket 7. The bent metal gasket 7 must be able to pass through the major diameter of the thread of the pipe joint 1; Step 2: If Figure 3 As shown: to avoid excessive deformation of the metal gasket at one time causing roughening of the gasket surface, after assembling the locking nut 2, the bent metal gasket 7 and the pipe joint 1, pre-press them with the pre-pressing tool upper die 9 and the pre-pressing tool lower die 10, so as to obtain the pre-pressed metal gasket 11, the inner diameter of which is smaller than the thread middle diameter of the pipe joint 1; Step 3: If Figure 4 As shown: the pre-pressed metal gasket 11 assembly is flattened by a flattening tool upper die 12 and a flattening tool lower die 13 to obtain a flattened metal gasket 14; because the flattening tool limits the inner diameter of the flattened metal gasket to be close to the diameter of the pipe joint back-cut groove, the outer diameter of the flattened metal gasket 14 is close to the diameter of the metal gasket 5 before bending, so that the assembled metal gasket 3 meets the design requirements.

[0019] The invention has stable and reliable processing, high qualified rate of installed pipe joints with metal washers and good batch consistency; it is easy to use and has low requirements on assembly personnel; it has high processing efficiency and reduces production costs.

Claims

1. A gasket assembly method for a pipe joint with a metal gasket, characterized in that: It includes the following steps: Step 1: bend the metal gasket (5) before bending through a deformation tool upper die (6) and a deformation tool lower die (8) to form a bent metal gasket (7). The bent metal gasket (7) must be able to pass through the major diameter of the thread of the pipe joint (1); Step 2: After assembling the locking nut (2), the bent metal washer (7) and the pipe joint (1), pre-pressing is performed using a pre-pressing tool upper die (9) and a pre-pressing tool lower die (10) to obtain a pre-pressed metal washer (11), wherein the inner diameter of the pre-pressed metal washer (11) is smaller than the thread diameter of the pipe joint (1); Step 3: The pre-pressed metal gasket (11) is assembled and flattened using an upper die (12) and a lower die (13) of a flattening tool to obtain a flattened metal gasket (14). Due to the limitation of the flattening tool, the inner diameter of the flattened metal gasket (14) is close to the diameter of the undercut groove of the pipe joint (1), and the outer diameter of the flattened metal gasket (14) is close to the diameter of the metal gasket (5) before bending.

Images