CN112443685A - High-temperature-resistant one-way valve and processing technology thereof - Google Patents
High-temperature-resistant one-way valve and processing technology thereof Download PDFInfo
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- CN112443685A CN112443685A CN201911094840.8A CN201911094840A CN112443685A CN 112443685 A CN112443685 A CN 112443685A CN 201911094840 A CN201911094840 A CN 201911094840A CN 112443685 A CN112443685 A CN 112443685A
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- flow guide
- sealing
- inner cavity
- valve
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16K—VALVES; TAPS; COCKS; ACTUATING-FLOATS; DEVICES FOR VENTING OR AERATING
- F16K15/00—Check valves
- F16K15/02—Check valves with guided rigid valve members
- F16K15/08—Check valves with guided rigid valve members shaped as rings
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23P—METAL-WORKING NOT OTHERWISE PROVIDED FOR; COMBINED OPERATIONS; UNIVERSAL MACHINE TOOLS
- B23P15/00—Making specific metal objects by operations not covered by a single other subclass or a group in this subclass
- B23P15/001—Making specific metal objects by operations not covered by a single other subclass or a group in this subclass valves or valve housings
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16K—VALVES; TAPS; COCKS; ACTUATING-FLOATS; DEVICES FOR VENTING OR AERATING
- F16K27/00—Construction of housing; Use of materials therefor
- F16K27/02—Construction of housing; Use of materials therefor of lift valves
- F16K27/0209—Check valves or pivoted valves
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16K—VALVES; TAPS; COCKS; ACTUATING-FLOATS; DEVICES FOR VENTING OR AERATING
- F16K27/00—Construction of housing; Use of materials therefor
- F16K27/02—Construction of housing; Use of materials therefor of lift valves
- F16K27/0254—Construction of housing; Use of materials therefor of lift valves with conical shaped valve members
Abstract
The invention relates to the technical field of valves, in particular to a high-temperature-resistant one-way valve and a processing technology thereof. The technical scheme is that the valve comprises a valve body, wherein the valve body is provided with an inner cavity, a fluid outlet communicated with the inner cavity is arranged above the inner cavity, a fluid inlet communicated with the inner cavity is arranged below the inner cavity, the inner cavity is divided into a flow guide section and a sealing section, and the sealing section is cylindrical; the valve core is movably arranged in the inner cavity and is divided into a flow guide body and a sealing body, a flow guide groove is longitudinally formed in the flow guide body, the flow guide body section is in clearance fit with the flow guide section, and the sealing body is matched with the sealing section. The one-way valve is designed without a spring, and the sealing effect is completed by the self gravity of the valve core, so that the technical problem that the sealing performance of the traditional one-way valve is lost due to the elastic failure of the spring in a high-temperature environment is solved; the one-way valve has simple structure and lower maintenance and repair cost; the check valve prolongs the service life and reduces the production cost and the maintenance cost of enterprises.
Description
Technical Field
The invention relates to the technical field of valves, in particular to a high-temperature-resistant one-way valve and a processing technology thereof.
Background
Although the variety of the one-way valves in the market is wide, the technical problems still exist due to the fact that most of the one-way valves are special in certain application environments, for example, under the high-temperature environment, the elasticity of the spring is accelerated and attenuated to finally lose the elasticity, the one-way valve loses the function, equipment is failed or production accidents occur, and even life safety is endangered due to the fact that the spring works under the high-temperature environment for a long time. Therefore, most of check valves are affected by high-temperature environment, the service life of the check valves is greatly shortened, the maintenance cost is increased for enterprises, the production efficiency is directly affected, and even potential safety hazards exist at any time.
Disclosure of Invention
One aspect of the present disclosure provides a check valve and a processing technique thereof, which aims to solve the problem of stability of the check valve in a high temperature environment, prolong the service life of the check valve, and save the maintenance cost.
In order to achieve the above objects, the present invention adopts the following technical solutions, and the present invention includes,
the valve body is provided with an inner cavity, a gas outlet communicated with the inner cavity is formed above the inner cavity, a gas inlet communicated with the inner cavity is formed below the inner cavity, the inner cavity comprises a flow guide section and a sealing section, the flow guide section is arranged above the sealing section, the sealing section is cylindrical, the flow guide section is square or cylindrical, and the inner diameter of the flow guide section is larger than that of the sealing section;
the valve core is movably arranged in the inner cavity of the valve body and is divided into a flow guide body and a sealing body, a flow guide groove is longitudinally formed in the flow guide body and is used for gas circulation when the check valve is opened, and the flow guide body is in clearance fit with the flow guide section; the sealing body is conical, and the sealing body is matched with the sealing section;
the inner diameter of the sealing section is smaller than the maximum outer diameter of the sealing body.
Furthermore, a check ring is arranged at the gas outlet, and a check ring groove matched with the check ring is arranged on the wall of the inner cavity.
Furthermore, a cover plate is arranged at the top of the valve body, a through hole is formed in the cover plate, and the through hole is communicated with the gas outlet.
Preferably, the sealing body is in the shape of a truncated cone, i.e. a truncated cone, and the inner diameter of the sealing section is between the outer diameters of the upper and lower bottom surfaces of the sealing body.
Preferably, the sealing body and the sealing section are matched in a sealing fit.
The processing technology of the high-temperature resistant one-way valve is technically characterized by comprising the processing technology of a valve core and a valve body,
the machining process of the valve core comprises the following steps:
(1) selecting a forging piece;
(2) roughly turning, namely turning the forged piece in the step (1) into a cylindrical flow guide body and a truncated cone-shaped sealing body, wherein the roughness is Ra3.2 um, and the conical surface allowance of the sealing body is 1 mm;
(3) checking the appearance quality, and checking whether the workpiece processed in the step (2) has forging defects;
(4) finish turning, finish turning the work piece of step (3), guarantee the sliding surface of the deflector and grinding allowance of the conical surface size of the seal body is no less than 0.15-0.2mm, the roughness reaches Ra1.6um, the upper plane of the deflector reserves the weight loss balancing piece allowance 0.2-0.5 mm;
(5) milling, namely milling the flow guide body obtained in the step (4) into a plurality of flow guide grooves, wherein the flow guide grooves are uniformly distributed on the circumference of the flow guide body;
(6) performing heat treatment on the workpiece obtained in the step (5) in a vacuum furnace at the temperature of 1270-;
(7) grinding, namely grinding the workpiece in the step (6) to enable the cylindrical surface of the flow guide body and the conical surface of the sealing body to be in smooth transition, wherein the roughness is Ra0.8um;
(8) removing the heavy object, namely removing the heavy object on the upper plane of the flow guide body in the step (7) to make the valve core accord with the design weight;
(9) strengthening treatment, namely strengthening the surface strength and the roughness of the workpiece in the step (8), wherein the surface strength HRC is not less than 65 and the roughness Ra0.2um is more than;
(10) checking the valve core;
the valve body machining process comprises the following steps:
(1) selecting a forging piece;
(2) rough turning, roughly machining the outer part of the forge piece in the step (1), and drilling a central inner hole;
(3) checking the appearance quality, and checking whether the workpiece processed in the step (2) has forging defects;
(4) performing heat treatment on the workpiece in the step (3), wherein the temperature is 900-;
(5) finish turning, finish machining the outer part and the inner hole of the workpiece in the step (4) to obtain a flat end face with the roughness of more than Ra1.6 um;
(6) turning around the workpiece in the step (5), aligning according to the excircle, finely machining the flow guide section of the inner cavity, flattening the end face and chamfering by 0.5x45 degrees, and turning a retainer ring groove;
(7) and testing the valve body.
And (3) the equipment used for strengthening treatment in the step (9) of the valve core processing technology is Haokou equipment.
Further, the process also comprises assembly and a compression test.
Compared with the prior art, the one-way valve has no spring design, and the sealing effect is completed through the self gravity of the valve core, so that the technical problem that the sealing performance of the traditional one-way valve is lost due to the elastic failure of the spring in a high-temperature environment is solved; secondly, the one-way valve is simple in structure and low in maintenance and repair cost; thirdly, the service life of the check valve is prolonged, and the production cost and the maintenance cost of enterprises are reduced.
Drawings
FIG. 1 is a schematic overall structure according to one aspect of the present disclosure;
FIG. 2 is a schematic view of a valve body structure according to one aspect of the present disclosure;
FIG. 3 is a schematic view of a valve cartridge configuration according to one aspect of the present disclosure;
FIG. 4 is a schematic illustration of a cross-sectional configuration of a valve cartridge according to one aspect of the present disclosure;
in the figure, 1-valve body, 2-valve core, 3-gas outlet, 4-gas inlet, 5-retainer ring, 6-diversion groove, 7-diversion section and 8-sealing section.
Detailed Description
The present invention will be further explained with reference to the embodiments, but the invention is not limited thereto, and the structures, the proportions, the sizes, and the like, which are shown in the drawings, are only used for matching with the disclosure of the specification, so as to be understood and read by those skilled in the art, and are not used for limiting the conditions under which the present invention can be implemented, so that the present invention has no technical essence, and any structural modification, changes in proportion, or adjustments in size, should still fall within the scope covered by the technical contents disclosed in the present invention without affecting the efficacy and the achievable purpose of the present invention. In addition, the terms "upper", "lower", "front", "rear" and "middle" used in the present specification are for clarity of description, and are not intended to limit the scope of the present invention, and the relative relationship between the terms and the relative positions may be changed or adjusted without substantial technical changes.
According to an embodiment of one aspect of the present disclosure, as shown in fig. 1 to 4, the high temperature resistant check valve includes a valve body 1, the valve body 1 is provided with an inner cavity, a gas outlet 3 communicated with the inner cavity is arranged above the inner cavity, a retainer ring 5 is arranged at the gas outlet 3, a retainer ring groove matched with the retainer ring 5 is arranged on the cavity wall of the inner cavity, a gas inlet 4 communicated with the inner cavity is arranged below the inner cavity, the inner cavity includes a flow guide section 7 and a sealing section 8, the flow guide section 7 is arranged above the sealing section 8, both the flow guide section 7 and the sealing section 8 are cylindrical, and the inner diameter of the flow guide section 7 is larger than the inner diameter of the;
the valve core 2 is movably arranged in the inner cavity of the valve body 1, the valve core 2 is divided into a flow guide body 9 and a sealing body 10, a flow guide groove 6 is longitudinally arranged on the flow guide body 9, the flow guide groove 6 is used for gas circulation when the check valve is opened, and the flow guide body 9 is in clearance fit with the flow guide section 7; the sealing body 10 is in a truncated cone shape, namely a circular truncated cone shape, the inner diameter of the sealing section 8 is between the outer diameters of the upper bottom surface and the lower bottom surface of the sealing body 10, and the sealing body 10 is in sealing fit with the sealing section 8.
The high-temperature-resistant check valve is vertically installed, namely, the lower end of the check valve is an inlet 4 for gas, the gas enters the valve body 1 from the lower part, the gas generates upward force on the valve core 2 after flowing into the valve body, when the upward force of the gas is greater than the gravity of the valve core 2, the check valve is opened, the gas is discharged from an outlet 3 of the check valve through a diversion groove 6 of the valve core 2, when the gas is cut off or the pressure of the gas is less than the gravity of the valve core 2, the valve core 2 is in sealing fit with a sealing section 8 of the valve body 1 under the action of gravity, and the check valve is closed.
If the outlet 3 of the one-way valve has backflow, namely, gas flows into the outlet, at the moment, the upward pressure of the gas entering from the inlet 4 of the one-way valve on the valve core 2 is larger than the gravity of the valve core 2 and the downward pressure of the gas entering from the outlet on the valve core 2.
A processing technique of a high-temperature resistant one-way valve, which comprises a processing technique of a valve core and a valve body,
the machining process of the valve core comprises the following steps:
(1) selecting a forging piece, selecting a W18Cr4V phi 25mm forging piece, wherein the annealing state HB of the forging piece is not more than 255;
(2) roughly turning, namely turning the forged piece in the step (1) into a cylindrical flow guide body and a truncated cone-shaped sealing body, wherein the roughness is Ra3.2 um, the outer diameter of the workpiece is phi 23mm, and the conical surface allowance of the sealing body is 1 mm;
(3) checking the appearance quality, and checking whether the workpiece processed in the step (2) has forging defects;
(4) finish turning, finish turning the work piece of step (3), guarantee the sliding surface of the deflector and grinding allowance of the conical surface size of the seal body is no less than 0.15-0.2mm, the external diameter of the work piece is phi 22(0/-0.02) mm, the roughness reaches Ra1.6um, the upper plane of the deflector reserves the weight reducing balance weight allowance of 0.2-0.5 mm;
(5) milling, namely milling 6 guide grooves with the depth of 3mm on the guide body obtained in the step (4), wherein the 6 guide grooves are uniformly distributed on the circumference of the guide body;
(6) performing heat treatment on the workpiece obtained in the step (5) in a vacuum furnace, wherein the temperature is 1280 ℃, the tempering temperature is 560 ℃, the workpiece is quenched by using heat treatment oil, and the HRC of the quenched workpiece is not less than 62;
(7) grinding, namely grinding the workpiece in the step (6), wherein the outer diameter of the workpiece is phi 22(-0.04) mm, so that the cylindrical surface of the flow guide body and the conical surface of the sealing body are in smooth transition, and the roughness is Ra0.8um;
(8) and (4) removing heavy grinding, wherein the upper plane of the flow guide body in the step (7) is subjected to removing heavy grinding, so that the weight of the valve core is 0.086 kg;
(9) strengthening treatment, namely strengthening the surface strength and the roughness of the workpiece in the step (8) by using Haokang energy equipment, wherein the surface strength HRC is not less than 65 and the roughness is more than Ra0.2um after processing;
(10) checking the valve core;
the valve body machining process comprises the following steps:
(1) selecting a forging piece, and selecting a 1Cr15Ni25Ti2MoVB phi 25mm forging piece;
(2) rough turning, roughly machining the outer part of the forge piece in the step (1), wherein the outer diameter of the forge piece is 22mm, and a central inner hole is drilled to 6 mm;
(3) checking the appearance quality, and checking whether the workpiece processed in the step (2) has forging defects;
(4) performing heat treatment, namely performing heat treatment on the workpiece in the step (3) at 900 ℃, performing oil quenching for 2 hours, preserving heat for 15 hours at 700 ℃, and performing air cooling to ensure that the hardness of the workpiece is HB 227-269;
(5) finish turning, finish turning the outer part of the workpiece in the step (4), wherein the outer circle is phi 21(-0.05) mm, the inner space is phi 8mm, the roughness is more than Ra1.6um, and the end surface is flat;
(6) turning around the workpiece in the step (5), aligning according to the excircle, and finely machining a flow guide section of the inner cavity, wherein the flow guide section is phi 12(+0.10/+0.07) mm, the end face is flat, and the angle is 0.5x45 degrees, and a retainer groove is turned;
(7) and testing the valve body.
And assembling the valve core and the valve body, and performing a compression test.
Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.
Claims (8)
1. A high temperature resistant check valve which characterized in that: comprises that
The valve body is provided with an inner cavity, a gas outlet communicated with the inner cavity is formed above the inner cavity, a gas inlet communicated with the inner cavity is formed below the inner cavity, the inner cavity comprises a flow guide section and a sealing section, the flow guide section is arranged above the sealing section, the sealing section is cylindrical, and the inner diameter of the flow guide section is larger than that of the sealing section;
the valve core is movably arranged in the inner cavity of the valve body and is divided into a flow guide body and a sealing body, a flow guide groove is longitudinally formed in the flow guide body and is used for gas circulation when the check valve is opened, and the flow guide body is in clearance fit with the flow guide section; the sealing body is conical, and the sealing body is matched with the sealing section;
the inner diameter of the sealing section is smaller than the maximum outer diameter of the sealing body.
2. A high temperature resistant one-way valve according to claim 1, wherein: and a check ring is arranged at the gas outlet, and a check ring groove matched with the check ring is arranged on the wall of the inner cavity.
3. A high temperature resistant one-way valve according to claim 1, wherein: the top of the valve body is provided with a cover plate, the cover plate is provided with a through hole, and the through hole is communicated with the gas outlet.
4. A high temperature resistant one-way valve according to claim 1, wherein: the sealing body is in a truncated cone shape, namely a circular truncated cone shape, and the inner diameter of the sealing section is between the outer diameters of the upper bottom surface and the lower bottom surface of the sealing body.
5. A high temperature resistant one-way valve according to claim 1, wherein: the sealing body is in sealing fit with the sealing section.
6. A process for manufacturing the high-temperature-resistant check valve according to any one of claims 1 to 5, wherein the process comprises the following steps: which comprises a processing technology of a valve core and a valve body,
the machining process of the valve core comprises the following steps:
(1) selecting a forging piece;
(2) roughly turning, namely turning the forged piece in the step (1) into a cylindrical flow guide body and a truncated cone-shaped sealing body, wherein the roughness is Ra3.2 um, and the conical surface allowance of the sealing body is 1 mm;
(3) checking the appearance quality, and checking whether the workpiece processed in the step (2) has forging defects;
(4) finish turning, finish turning the work piece of step (3), guarantee the sliding surface of the deflector and grinding allowance of the conical surface size of the seal body is no less than 0.15-0.2mm, the roughness reaches Ra1.6um, the upper plane of the deflector reserves the weight loss balancing piece allowance 0.2-0.5 mm;
(5) milling, namely milling the flow guide body obtained in the step (4) into a plurality of flow guide grooves, wherein the flow guide grooves are uniformly distributed on the circumference of the flow guide body;
(6) performing heat treatment on the workpiece obtained in the step (5) in a vacuum furnace at the temperature of 1270-;
(7) grinding, namely grinding the workpiece in the step (6) to enable the cylindrical surface of the flow guide body and the conical surface of the sealing body to be in smooth transition, wherein the roughness is Ra0.8um;
(8) removing the heavy object, namely removing the heavy object on the upper plane of the flow guide body in the step (7) to make the valve core accord with the design weight;
(9) strengthening treatment, namely strengthening the surface strength and the roughness of the workpiece in the step (8), wherein the surface strength HRC is not less than 65 and the roughness Ra0.2um is more than;
(10) checking the valve core;
the valve body machining process comprises the following steps:
(1) selecting a forging piece;
(2) rough turning, roughly machining the outer part of the forge piece in the step (1), and drilling a central inner hole;
(3) checking the appearance quality, and checking whether the workpiece processed in the step (2) has forging defects;
(4) performing heat treatment on the workpiece in the step (3), wherein the temperature is 900-;
(5) finish turning, finish machining the outer part and the inner hole of the workpiece in the step (4) to obtain a flat end face with the roughness of more than Ra1.6 um;
(6) turning around the workpiece in the step (5), aligning according to the excircle, finely machining the flow guide section of the inner cavity, flattening the end face and chamfering by 0.5x45 degrees, and turning a retainer ring groove;
(7) and testing the valve body.
7. The process according to claim 6, characterized in that: and (3) the equipment used for strengthening treatment in the step (9) of the valve core processing technology is Haokou equipment.
8. The process according to claim 6, characterized in that: also includes assembling and pressing test.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910819055 | 2019-08-30 | ||
| CN2019108190558 | 2019-08-30 |
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| Publication Number | Publication Date |
|---|---|
| CN112443685A true CN112443685A (en) | 2021-03-05 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201911094840.8A Pending CN112443685A (en) | 2019-08-30 | 2019-11-11 | High-temperature-resistant one-way valve and processing technology thereof |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115419824A (en) * | 2022-09-06 | 2022-12-02 | 大连大特气体有限公司 | Vaporizer capable of improving vaporization efficiency |
| WO2023040315A1 (en) * | 2021-09-19 | 2023-03-23 | 青岛海尔空调器有限总公司 | One-way valve, heat exchanger, refrigeration circulation system, and air conditioner |
-
2019
- 2019-11-11 CN CN201911094840.8A patent/CN112443685A/en active Pending
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2023040315A1 (en) * | 2021-09-19 | 2023-03-23 | 青岛海尔空调器有限总公司 | One-way valve, heat exchanger, refrigeration circulation system, and air conditioner |
| WO2023040317A1 (en) * | 2021-09-19 | 2023-03-23 | 青岛海尔空调器有限总公司 | One-way valve, heat exchanger, refrigeration cycle system, and air conditioner |
| CN115419824A (en) * | 2022-09-06 | 2022-12-02 | 大连大特气体有限公司 | Vaporizer capable of improving vaporization efficiency |
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