Pilot operated sealing threaded joints

Abstract

The present invention relates to a pilot-type sealing threaded joint, which is characterized in that it includes a joint body provided with a central through hole, a first threaded portion consistent with the thread of the connected container bottle mouth is provided at the lower end of the joint body, and a second threaded portion for connecting a quick joint is provided at the upper end of the joint body; a rotary pressure head is sleeved on the joint body and threadedly connected to the joint body, and a first O-ring is provided between the rotary pressure head and the joint body; a pressure plate groove and a gasket groove are provided on the rotary pressure head, and the pressure plate and the sealing gasket are respectively arranged in the pressure plate groove and the gasket groove, and a second O-ring is provided between the outer cylindrical surface of the pressure plate and the inner cylindrical surface of the pressure plate groove; at least one axial pilot groove is provided on the surface of the joint body above the first threaded portion of the joint body, and when the rotary pressure head is tightly against the connected container bottle mouth, the pilot groove extends to the top of the pressure plate. The present invention has a simple and compact structure, low manufacturing cost, convenient and quick operation, enhanced sealing effect, and can be applied to pressure testing of double-head or multi-head pressure vessels.

Description

Technical Field

[0001] The invention relates to a pressure vessel pressurization testing device, in particular to a pilot type sealing threaded joint. Background Art

[0002] Generally, tapered threads are used as the thread of the bottle mouth of pressure vessels. In order to ensure the sealing of the bottle mouth during the pressure test, the following methods are generally used:

[0003] 1. Use the plane sealing method, use the sealing gasket to directly contact the end face of the bottle mouth and ensure sufficient clamping force to achieve the sealing effect. This method is mainly suitable for pressure tests where the center of the bottle mouth thread is concentric with the axis of the container, and the test pressure generally does not exceed 5MPa. This method can achieve electrical control, but its applicability is limited and the test pressure is low. If the test pressure needs to be increased, the clamping force needs to be increased, and the bottle body also needs to withstand this clamping force.

[0004] 2. Use internal pressure sealing threaded joints, such as the special joint with publication number 102996956A (named "Special Pressure Joint for Water Pressure Test of Pressure Vessels"). This joint is mainly suitable for pressure tests where the center of the bottle mouth thread is concentric with the axis of the container, and the test pressure generally does not exceed 40MPa. This type of joint has a complex joint structure and a large appearance, and cannot be used in situations with small spaces.

[0005] 3. Directly use tapered threads for sealing. This method requires adding sealing materials (such as raw tape) to the threaded part and tightening the thread to a larger torque to achieve the sealing effect, which is time-consuming and labor-intensive. Summary of the invention

[0006] In view of the above problems, the applicant has conducted research and improvement, and provided a pilot-type sealing threaded joint with a simple and compact structure, low manufacturing cost, convenient and quick operation, enhanced sealing effect, and applicable to pressure testing of double-head or multi-head pressure vessels.

[0007] In order to solve the above technical problems, the present invention adopts the following technical solutions:

[0008] A pilot-type sealing threaded joint, comprising a joint body provided with a central through hole, the lower end of the joint body being provided with a first threaded portion consistent with the thread of the bottle mouth of the connected container, and the upper end of the joint body being provided with a second threaded portion for connecting a quick joint; the middle part of the joint body being provided with an external thread, a rotary pressure head being sleeved on the joint body and threadedly connected to the joint body, a first O-ring being provided between the rotary pressure head and the joint body; a pressure plate groove and a gasket groove being provided on the rotary pressure head, a pressure plate and a sealing gasket being respectively arranged in the pressure plate groove and the gasket groove, a second O-ring being provided between the outer circular surface of the pressure plate and the inner circular surface of the pressure plate groove; at least one axial pilot groove is provided on the surface of the joint body above the first threaded portion of the joint body, and when the rotary pressure head is tightly against the bottle mouth of the connected container, the pilot groove extends to above the pressure plate.

[0009] Further:

[0010] Two axial guide grooves are symmetrically arranged on the surface of the joint body.

[0011] An annular protrusion is provided on the contact surface between the pressing plate and the sealing gasket.

[0012] The cross section of the annular protrusion is a triangle.

[0013] The technical effects of the present invention are:

[0014] The invention discloses a pilot-type sealing threaded joint, which has a simple and compact structure, low manufacturing cost, convenient and quick operation, enhanced sealing effect, and can be applied to pressure testing of double-head or multi-head pressure vessels. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a schematic diagram of the structure of the present invention.

[0016] Figure 2 It is a schematic diagram of the local structure of the joint body.

[0017] Figure 3 It is a structural schematic diagram of the pressure plate. DETAILED DESCRIPTION

[0018] The specific implementation modes of the present invention will be further described in detail below in conjunction with the accompanying drawings.

[0019] like Figure 1 , 2As shown in Figure 3, the present invention includes a joint body 6 provided with a central through hole 64, a first threaded portion 61 consistent with the thread of the mouth of the connected container is provided at the lower end of the joint body 6, and a second threaded portion 65 for connecting a quick connector is provided at the upper end of the joint body 6. In this embodiment, the first threaded portion 61 is a tapered thread consistent with the thread of the mouth of the connected container, and the second threaded portion 65 is an internal thread. The second threaded portion 65 can be easily connected to the pressure test pipeline through a quick connector. An external thread 63 is provided in the middle of the joint body 6, and the rotary pressure head 1 is sleeved on the joint body 6 and is threadedly connected to the joint body 6 through the external thread 63. A first O-ring 5 is provided between the rotary pressure head 1 and the joint body 6. A pressure plate groove and a gasket groove are provided on the rotary pressure head 1, and the pressure plate 4 and the sealing gasket 2 are respectively arranged in the pressure plate groove and the gasket groove, and a second O-ring 3 is provided between the outer cylindrical surface of the pressure plate 4 and the inner cylindrical surface of the pressure plate groove. At least one axial pilot groove 62 is provided on the surface of the joint body 6 above the first threaded portion 61 of the joint body 6. When the rotary pressure head 1 is pressed against the mouth of the connected container, the pilot groove 62 extends to the top of the pressure plate 4. In this embodiment, two axial pilot grooves 62 are symmetrically provided on the surface of the joint body 6. An annular protrusion 41 is provided on the contact surface between the pressure plate 4 and the sealing gasket 2. The cross section of the annular protrusion 41 is triangular. When the pressure plate 4 and the sealing gasket 2 are pressed against the mouth of the connected container, the annular protrusion 41 can ensure the sealing of the joint surface.

[0020] When pressure testing a pressure vessel,

[0021] 1. First, manually rotate the joint body 6 to screw its first threaded portion 61 into the thread of the pressure container mouth to complete the connection with the pressure container;

[0022] 2. Manually rotate the rotary pressing head 1 so that the rotary pressing head 1 and the pressing plate 4 press the sealing gasket 2 against the end surface of the pressure vessel mouth to ensure the initial sealing;

[0023] 3. Connect the second threaded portion 65 of the quick connector body 6 to the pressure test pipeline through the quick connector;

[0024] 4. Pressurize the pressure vessel. The pressure in the container is transmitted to the upper side of the pressure plate 4 through the gap between the pressure plate 4, the sealing gasket 2 and the joint body 6 (there are gaps between the pressure plate 4, the sealing gasket 2 and the outer circumferential surface of the joint body 6) and the pilot groove 62, balancing the influence of the pressure in the container on the sealing structure and further providing the sealing compression force to enhance the sealing performance of the sealing end face.

[0025] The pilot-type sealing threaded joint of the present invention adopts a plane sealing method and is connected manually. Due to the effect of the pilot groove, the influence of the pressure in the container on the sealing structure is balanced and the sealing compression force is further provided, so that the sealing effect is easily enhanced. The structure is simple, the manufacturing cost is low, and the operation is convenient and fast. When a double-head or multi-head pressure vessel is subjected to a pressure test, since the multiple threaded bottle mouths of such pressure vessels are not consistent with the center of the pressure vessel, the existing joint sealing method cannot adapt and cannot easily and efficiently complete the sealing connection. The present invention is applicable to pressure vessels in various situations, especially multi-head pressure vessels.

Claims

1. A pilot-type sealing threaded joint, characterized in that: It includes a connector body provided with a central through hole, the lower end of the connector body is provided with a first threaded portion consistent with the thread of the bottle mouth of the connected container, and the upper end of the connector body is provided with a second threaded portion for connecting the quick connector; the middle part of the connector body is provided with an external thread, a rotary pressure head is sleeved on the connector body and threadedly connected to the connector body, and a first O-ring is provided between the rotary pressure head and the connector body; the rotary pressure head is provided with a pressure plate groove and a gasket groove, the pressure plate and the sealing gasket are respectively arranged in the pressure plate groove and the gasket groove, and a second O-ring is provided between the outer circular surface of the pressure plate and the inner circular surface of the pressure plate groove; the surface of the connector body above the first threaded portion of the connector body is provided with at least one axial pilot groove, and when the rotary pressure head is pressed tightly on the bottle mouth of the connected container, the pilot groove extends to the top of the pressure plate.

2. The pilot-operated sealing threaded joint according to claim 1, characterized in that: Two axial guide grooves are symmetrically arranged on the surface of the joint body.

3. The pilot-operated sealing threaded joint according to claim 1, characterized in that: An annular protrusion is provided on the contact surface between the pressing plate and the sealing gasket.

4. The pilot-operated sealing threaded joint according to claim 3, characterized in that: The cross section of the annular protrusion is a triangle.

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