CN209892816U - Low-pressure fine-adjustment built-in dead weight type safety valve - Google Patents
Low-pressure fine-adjustment built-in dead weight type safety valve Download PDFInfo
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- CN209892816U CN209892816U CN201920587582.6U CN201920587582U CN209892816U CN 209892816 U CN209892816 U CN 209892816U CN 201920587582 U CN201920587582 U CN 201920587582U CN 209892816 U CN209892816 U CN 209892816U
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Abstract
Low pressure fine setting embeds dead weight formula relief valve, which comprises a valve body, the weight, the disk seat, the valve gap, weight slidable mounting is in the valve gap, upper portion in the weight lower part stretches into the valve body, penetrating guiding hole about having seted up in the weight, install elasticity centering fine-tuning in the guiding hole, weight bottom fixedly connected with outer connecting cylinder, have an inner connecting cylinder with axial fixed mounting in the outer connecting cylinder, the fixed baffle that is provided with is established to inner connecting cylinder inside, outer connecting cylinder lower extreme is with axial fixedly connected with recoil dish, the outer circumference an organic whole of recoil dish bottom is provided with the retaining ring, the level is provided with the valve clack with disk seat seal fit in the retaining ring. The utility model discloses a sealing performance is high, and valve clack lift direction and straightness stability that hangs down are high, and the elasticity adjustment of the dead weight cooperation spring of weight can make valve sensitivity high, and it is opened, take-off, returns seat action performance and action stability can be good. The method is suitable for equipment and pipelines of class E steam, air boilers and similar media with low pressure and working temperature of less than or equal to 200 ℃.
Description
Technical Field
The utility model belongs to the technical field of the valve, concretely relates to low pressure fine setting embeds dead weight formula relief valve.
Background
The low-pressure fine-tuning built-in dead weight type safety valve is used in a thermodynamic system as an overpressure protection valve used on a steam boiler, a pressure steam container and a pipeline. The low-pressure full-open type safety valve used for a thermodynamic system, a steam boiler, a pressure steam container and a pipeline in the prior art has a simple structure, the valve clack is a plane sealing surface, no protection device is arranged outside the heavy hammer, and the normal work of the valve is easily influenced by the vibration of the external environment or the presence of dust; the action performance of the valve is unstable and can not meet the standard requirement; the pressure is difficult to adjust when deviating, and sealed also easy leakage, and user's reflection suggestion is bigger.
SUMMERY OF THE UTILITY MODEL
The utility model discloses a solve the weak point among the prior art, provide a leakproofness well, stability is strong, long service life's built-in dead weight formula relief valve is finely tuned to low pressure.
In order to solve the technical problem, the utility model adopts the following technical scheme: a low-pressure fine-tuning built-in static-load safety valve comprises a valve body and a heavy hammer, wherein mounting interfaces are arranged on the right side and the bottom of the valve body, a valve seat is arranged on the lower portion in the valve body, the top of the valve body is matched and centered through a spigot structure, a valve cover is fixedly arranged on the top of the valve body through a mounting bolt, the heavy hammer is installed in the valve cover in a sliding guide mode, the lower portion of the heavy hammer extends into the upper portion in the valve body, a guide hole which is through up and down is formed in the heavy hammer, the center line of the guide hole is overlapped with the center line of the valve seat, an elastic centering fine-tuning mechanism is installed in the guide hole, the bottom of the heavy hammer is fixedly connected with an outer connecting cylinder which is the same as the center line of the guide hole and has the same inner diameter, an inner connecting cylinder is coaxially and fixedly installed in the outer connecting cylinder, a partition plate, the level is provided with the valve clack in the retaining ring, and outer connecting cylinder end opening is provided with the spacing ring that the internal diameter is less than outer connecting cylinder internal diameter, and the valve clack top is provided with upwards passes the connector that the spacing ring stretches into outer connecting cylinder inside, and the outer circumference of connector is provided with the snap ring that is located the spacing ring top, and the valve clack bottom surface is provided with seal ring, and the disk seat up end is provided with seal ring down. Under the action of the gravity of the heavy hammer and the elastic centering fine adjustment mechanism, the upper sealing washer is pressed and sealed on the lower sealing washer.
Elastic centering fine-tuning includes the guide post, adjusting bolt, a spring, the cushion, go up the apical seat and apical seat down, on the baffle in the connecting cylinder including the cushion sets up, apical seat lower extreme roof pressure is on the cushion down, the guide post slides and sets up in the guiding hole, the mounting groove has been seted up to the guide post bottom, the center department of the top surface of guide post upper surface and mounting groove is provided with upper conical groove and lower tapered groove respectively, it sets up in the mounting groove to go up the apical seat, the top of the upper end of going up the apical seat stretches into the upper conical groove, the upper end and the lower extreme of spring are installed respectively in apical seat lower part and apical seat upper portion down, adjusting bolt sets up perpendicularly, adjusting bolt threaded connection is on the valve bonnet, the adjusting bolt lower extreme is sharp-pointed structure, adjusting bolt lower extreme roof pressure is in upper conical groove, threaded connection has the first lock nut with valve gap top crimping complex on the adjusting bolt.
The excircle of the upper part of the valve seat is in threaded connection with an adjusting ring, the inner circle of the lower part of the check ring and the excircle of the upper part of the adjusting ring are both in a conical structure with a thin upper part and a thick lower part, and the upper part of the adjusting ring extends into the conical structure of the check ring and forms a conical adjusting gap with the conical structure.
The lower part of the left side of the valve body is in threaded connection with a locking screw rod, the locking screw rod is horizontally arranged along the left-right direction, the outer circle of the adjusting ring is of a toothed structure, the right end of the locking screw rod extends into a groove formed between the toothed structures, and a second locking nut in top press fit with the left side face of the valve body is in threaded connection with the locking screw rod.
The excircle threaded connection of an internal connecting cylinder is inside an external connecting cylinder, and the lower end of the external connecting cylinder is connected with the excircle spot welding of the internal connecting cylinder.
Adopt above-mentioned technical scheme, the utility model discloses following technological effect has:
1. the structure of a built-in static-load sealing surface is adopted: the valve body sealing medium, the fluid medium can seal in the valve body through the valve seat, valve clack; the weight hammer is combined with the recoil disc, and the static gravity of the weight hammer is balanced with the opening pressure, so that the sealing is more reliable; the adjusting clearance between the adjusting ring matched with the valve seat and the retaining ring at the bottom of the recoil disc enables the acting area and recoil of the airflow when the valve is opened and bounced to have centering performance, changes the recoil direction of the airflow, and enables the pressure of the valve to be easily adjusted to the standard requirement and stable action repeatability. And make the dust can not get into inside the fine-tuning of elastic centering, reduce the motion friction between the guide part, improve and stabilized the performance of valve.
2. Adopt the structure of low pressure fine setting: the spring acts on the upper part of the recoil disc, and the set pressure of the low-pressure safety valve is adjusted in a micro-scale mode by screwing the thread between the adjusting bolt and the valve cover. The gravity center of the heavy hammer moves downwards to directly act on the valve clack, and the size deviation of components directly influences the action performance of the valve at the beginning of opening and jumping of the valve. In the low-pressure fine adjustment structure, the spring is designed on the upper part of the recoil disc to assist in fine adjustment of pressure, and the valve clack is stable in performance and fast in seat returning and sealing when being opened, jumped and discharged; in addition, spring force acts on the valve clack and the valve seat in a micro-scale manner, so that the upper sealing washer is always contacted with the lower sealing washer in the transportation process of the safety valve, collision cannot be generated, and damage to the sealing surface is reduced.
3. The arrangement of the upper conical groove, the lower part of the upper tip seat and the lower tip seat can ensure that the acting force of the spring acts on the partition plate, and the partition plate acts on the recoil disc downwards to achieve the centering effect, so that the stability of the valve during opening is ensured.
4. When the air flow recoil direction needs to be adjusted, the second locking nut is loosened, then the locking screw is loosened and taken out, the tooth shifting rotation operation is carried out on the tooth-shaped structure through the locking screw mounting screw hole on the left side of the valve body, the adjusting ring is enabled to rotate to ascend or descend outside the valve seat, and the purpose of adjusting the conical adjusting gap formed between the upper portion of the adjusting ring and the conical structure of the check ring is achieved.
5. The distance from the upper end face of the heavy hammer to the inner end face of the valve cover is the designed opening height of the valve; an internal connection section of thick bamboo and external connection section of thick bamboo threaded connection can make things convenient for adjusting valve's height of opening when initial installation, treat altitude mixture control to when the regulation requires to the regulation, the excircle spot welding of external connection section of thick bamboo lower extreme and internal connection section of thick bamboo is connected.
To sum up, the installation interface at the bottom of the valve body of the utility model is installed on the pressure vessel or the pipeline, and under the condition of lower pressure of the working pipeline, a fine tuning space exists, so that the pressure vessel and the pipeline are better protected; the valve clack, the valve seat, the heavy hammer and other built-in structures enable the valve clack, the valve seat, the heavy hammer and other built-in structures to be free from the influence of external environment under the condition that the external environment has media such as large pollution, particles, dust and the like, and sealing can be better completed; and can be adjusted when the pressure needs to be adjusted slightly. The safety valve is opened under low pressure, the jump discharge performance and the seat return performance meet the standard requirements, and the repeatability of the performance is stable and reliable. The defects that the external design of the heavy hammer is easy to leak, the valve is opened when being damaged by external cushion, the jump and the seat return action performance can not meet the standard requirement, and the action repeatability is not good are overcome.
The utility model discloses a sealing performance is high, and valve clack lift direction and straightness stability that hangs down are high, and the elasticity adjustment of the dead weight cooperation spring of weight can make valve sensitivity high, and it is opened, take-off, returns seat action performance and action stability can be good. The method is suitable for equipment and pipelines of class E steam, air boilers and similar media with low pressure and working temperature of less than or equal to 200 ℃.
Drawings
Fig. 1 is a schematic structural diagram of the present invention.
Detailed Description
As shown in figure 1, the low-pressure fine-tuning built-in dead weight type safety valve of the utility model comprises a valve body 1 and a heavy hammer 2, the right side and the bottom of the valve body 1 are provided with installation interfaces 3, the lower part in the valve body 1 is provided with a valve seat 4, the top of the valve body 1 is matched and centered through a spigot structure and fixedly provided with a valve cover 6 through an installation bolt 5, the valve cover 6 and the valve body 1 are matched with each other with the matching precision of a convex-concave spigot, the valve cover 6 is ensured to be on the same central line with the valve body 1 and the valve seat 4, the heavy hammer 2 is slidably arranged in the valve cover 6, the excircle of the heavy hammer 2 is matched with the inner circle of the valve cover 6, the lifting total guide is realized when the valve is opened, discharged and returned to the seat, the lower part of the heavy hammer 2 extends into the upper part in the valve body 1, an upper and lower guide hole 7 which is through is arranged in the valve body 2, the, an inner connecting cylinder 9 is coaxially and fixedly installed in the outer connecting cylinder 8, a partition plate 10 is fixedly arranged in the inner connecting cylinder 9, the upper end and the lower end of the elastic centering fine adjustment mechanism are respectively in jacking fit with the valve cover 6 and the partition plate 10, a recoil disc 11 is coaxially and fixedly connected with the lower end of the outer connecting cylinder 8, a check ring 12 is integrally arranged on the outer circumference of the bottom of the recoil disc 11, a valve flap 13 is horizontally arranged in the check ring 12, a limit ring 14 with the inner diameter smaller than that of the outer connecting cylinder 8 is arranged at the lower port of the outer connecting cylinder 8, a connector 15 upwards penetrating through the limit ring 14 and extending into the outer connecting cylinder 8 is arranged at the top of the valve flap 13, a snap ring 16 positioned above the limit ring 14 is arranged on the outer circumference of the connector 15, an upper sealing washer 17 is arranged on the. Under the action of the self-gravity of the weight 2 and the elastic centering fine adjustment mechanism, the upper sealing washer 17 is pressed and sealed on the lower sealing washer 18.
The elastic centering fine adjustment mechanism comprises a guide column 19, an adjusting bolt 20, a spring 21, a cushion block 22, an upper tip seat 23 and a lower tip seat 24, the cushion block 22 is arranged on the partition board 10 in the inner connecting cylinder 9, the lower end of the lower tip seat 24 is pressed against the cushion block 22, the guide column 19 is arranged in the guide hole 7 in a sliding manner, the bottom of the guide column 19 is provided with a mounting groove 25, the center of the upper surface of the guide column 19 and the center of the top surface of the mounting groove 25 are respectively provided with an upper conical groove 26 and a lower conical groove 27, the upper tip seat 23 is arranged in the mounting groove 25, the upper tip of the upper tip seat 23 extends into the upper conical groove 26, the upper end and the lower end of the spring 21 are respectively arranged on the lower part of the upper tip seat 23 and the upper part of the lower tip seat 24, the adjusting bolt 20 is vertically arranged, the adjusting bolt 20 is in threaded connection with the valve cover 6, the lower end of the adjusting bolt 20 is of a, the adjusting bolt 20 is screwed with a first locking nut 28 which is in press fit with the top of the valve cover 6.
An adjusting ring 29 is in threaded connection with the outer circle of the upper portion of the valve seat 4, the inner circle of the lower portion of the check ring 12 and the outer circle of the upper portion of the adjusting ring 29 are both in a conical structure with a thin upper portion and a thick lower portion, and the upper portion of the adjusting ring 29 extends into the conical structure of the check ring 12 and forms a conical adjusting gap 30 with the conical structure.
The lower part of the left side of the valve body 1 is in threaded connection with a locking screw 31, the locking screw 31 is horizontally arranged along the left-right direction, the outer circle of the adjusting ring 29 is in a toothed structure 32, the right end of the locking screw 31 extends into a groove formed between the toothed structures 32, and the locking screw 31 is in threaded connection with a second locking nut 33 in top press fit with the left side surface of the valve body 1.
The excircle threaded connection of an internal connecting cylinder 9 is inside an external connecting cylinder 8, and the lower end of the external connecting cylinder 8 is connected with the excircle spot welding of the internal connecting cylinder 9.
The utility model discloses a theory of operation and technological effect do:
1. the structure of a built-in static-load sealing surface is adopted: the valve body 1 is sealed with a medium, and a fluid medium can be sealed in the valve body 1 through the valve seat 4 and the valve clack 13; the weight 2 is combined with the recoil disc 11, and the static gravity of the weight is balanced with the opening pressure, so that the sealing is more reliable; an adjusting gap 30 between an adjusting ring 29 matched with the valve seat 4 and a retainer ring 12 at the bottom of a recoil disc 11 enables the acting area and recoil of air flow during the opening and tripping of the valve to have centering performance, changes the recoil direction of the air flow, and enables the opening, tripping and recoil pressure of the valve to be easily adjusted to the standard requirement and stable action repeatability. And make the dust can not get into inside the fine-tuning of elastic centering, reduce the motion friction between the guide part, improve and stabilized the performance of valve.
2. Adopt the structure of low pressure fine setting: the spring 21 acts on the upper part of the recoil disc 11, and the set pressure of the low-pressure safety valve is slightly adjusted by screwing the thread between the adjusting bolt 20 and the valve cover 6. The gravity center of the weight 2 moves downwards to directly act on the valve clack 13, and the size deviation of the components directly influences the action performance of the valve at the beginning of opening and jumping of the valve. In the low-pressure fine adjustment structure, a spring 21 is designed at the upper part of the recoil disc 11 to assist in fine adjustment of pressure, and the valve clack 13 is stable in performance and fast in seat returning and sealing when being opened, jumped and discharged; in addition, the force of the spring 21 slightly acts on the valve clack 13 and the valve seat 4, so that the upper sealing washer 17 is always contacted with the lower sealing washer 18 in the transportation process of the safety valve, collision cannot occur, and the damage to the sealing surface is reduced.
3. The arrangement of the upper tapered groove 26, the lower tapered groove 27, the lower portion of the upper seat 23 and the lower seat 24 ensures that the force of the spring 21 acts on the diaphragm 10, and the downward action of the diaphragm 10 on the recoil disc 11 has a centering effect, ensuring the stability of the valve when opening.
4. When the air flow recoil direction needs to be adjusted, the second locking nut 33 is loosened, then the locking screw 31 is loosened and disassembled, the tooth shifting rotation operation is carried out on the tooth-shaped structure 32 through the mounting screw hole of the locking screw 31 on the left side of the valve body 1, so that the adjusting ring 29 rotates to ascend or descend outside the valve seat 4, and the purpose of adjusting the conical adjusting gap 30 formed between the upper part of the adjusting ring 29 and the conical structure of the retainer ring 12 is achieved.
5. The distance from the upper end surface of the heavy hammer 2 to the inner end surface of the valve cover 6 is the designed opening height of the valve; an inner connecting cylinder 9 and an outer connecting cylinder 8 are in threaded connection, the opening height of the valve can be conveniently adjusted during initial installation, and when the height is adjusted to the specified requirement, the lower end of the outer connecting cylinder 8 is connected with the outer circle of the inner connecting cylinder 9 in a spot welding mode.
The present embodiment is not intended to limit the shape, material, structure, etc. of the present invention in any form, and all of the technical matters of the present invention belong to the protection scope of the present invention to any simple modification, equivalent change and modification made by the above embodiments.
Claims (5)
1. Low pressure fine setting embeds dead weight formula relief valve, including valve body and weight, valve body right side and bottom all are provided with the installation interface, and the lower part is provided with the disk seat in the valve body, and the valve body top is through tang structure cooperation centering and through the fixed valve gap that is provided with of construction bolt, its characterized in that: the heavy hammer is arranged in the valve cover in a sliding guiding manner, the lower part of the heavy hammer extends into the upper part in the valve body, a guide hole which is through up and down is arranged in the heavy hammer, the central line of the guide hole is coincided with the central line of the valve seat, an elastic centering fine adjustment mechanism is arranged in the guide hole, the bottom of the heavy hammer is fixedly connected with an outer connecting cylinder which is the same with the central line of the guide hole and has the same inner diameter as the guide hole, an inner connecting cylinder is coaxially and fixedly arranged in the outer connecting cylinder, a partition plate is fixedly arranged in the inner connecting cylinder, the upper end and the lower end of the elastic centering fine adjustment mechanism are respectively in jacking fit with the valve cover and the partition plate, the lower end of the outer connecting cylinder is coaxially and fixedly connected with a recoil disc, a check ring is integrally arranged on the outer circumference at the bottom of the recoil disc, a valve clack is horizontally, a snap ring positioned above the limiting ring is arranged on the outer circumference of the connector, an upper sealing washer is arranged on the bottom surface of the valve clack, and a lower sealing washer is arranged on the upper end surface of the valve seat;
under the action of the gravity of the heavy hammer and the elastic centering fine adjustment mechanism, the upper sealing washer is pressed and sealed on the lower sealing washer.
2. The low pressure trim built-in dead weight relief valve of claim 1, wherein: elastic centering fine-tuning includes the guide post, adjusting bolt, a spring, the cushion, go up the apical seat and apical seat down, on the baffle in the connecting cylinder including the cushion sets up, apical seat lower extreme roof pressure is on the cushion down, the guide post slides and sets up in the guiding hole, the mounting groove has been seted up to the guide post bottom, the center department of the top surface of guide post upper surface and mounting groove is provided with upper conical groove and lower tapered groove respectively, it sets up in the mounting groove to go up the apical seat, the top of the upper end of going up the apical seat stretches into the upper conical groove, the upper end and the lower extreme of spring are installed respectively in apical seat lower part and apical seat upper portion down, adjusting bolt sets up perpendicularly, adjusting bolt threaded connection is on the valve bonnet, the adjusting bolt lower extreme is sharp-pointed structure, adjusting bolt lower extreme roof pressure is in upper conical groove, threaded connection has the first lock nut with valve gap top crimping complex on the adjusting bolt.
3. The low pressure trim built-in dead weight relief valve of claim 1, wherein: the excircle of the upper part of the valve seat is in threaded connection with an adjusting ring, the inner circle of the lower part of the check ring and the excircle of the upper part of the adjusting ring are both in a conical structure with a thin upper part and a thick lower part, and the upper part of the adjusting ring extends into the conical structure of the check ring and forms a conical adjusting gap with the conical structure.
4. The low pressure trim built-in dead weight relief valve of claim 3, wherein: the lower part of the left side of the valve body is in threaded connection with a locking screw rod, the locking screw rod is horizontally arranged along the left-right direction, the outer circle of the adjusting ring is of a toothed structure, the right end of the locking screw rod extends into a groove formed between the toothed structures, and a second locking nut in top press fit with the left side face of the valve body is in threaded connection with the locking screw rod.
5. The low pressure trim built-in dead weight relief valve of claim 1, wherein: the excircle threaded connection of an internal connecting cylinder is inside an external connecting cylinder, and the lower end of the external connecting cylinder is connected with the excircle spot welding of the internal connecting cylinder.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201920587582.6U CN209892816U (en) | 2019-04-26 | 2019-04-26 | Low-pressure fine-adjustment built-in dead weight type safety valve |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201920587582.6U CN209892816U (en) | 2019-04-26 | 2019-04-26 | Low-pressure fine-adjustment built-in dead weight type safety valve |
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| Publication Number | Publication Date |
|---|---|
| CN209892816U true CN209892816U (en) | 2020-01-03 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201920587582.6U Active CN209892816U (en) | 2019-04-26 | 2019-04-26 | Low-pressure fine-adjustment built-in dead weight type safety valve |
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| CN (1) | CN209892816U (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109958802A (en) * | 2019-04-26 | 2019-07-02 | 开封市瑞发高中压阀门有限公司 | Low pressure finely tunes built-in dead weight type safety valve |
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2019
- 2019-04-26 CN CN201920587582.6U patent/CN209892816U/en active Active
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109958802A (en) * | 2019-04-26 | 2019-07-02 | 开封市瑞发高中压阀门有限公司 | Low pressure finely tunes built-in dead weight type safety valve |
| CN109958802B (en) * | 2019-04-26 | 2024-04-02 | 开封市瑞发高中压阀门有限公司 | Low-pressure fine-tuning built-in dead weight type safety valve |
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