Integrated liquid outlet one-way valve structure of cold-end compression cylinder of LNG (Liquefied Natural Gas) booster pump

Abstract

The utility model relates to the technical field of LNG booster pumps, in particular to an integrated liquid outlet one-way valve structure of a cold-end compression cylinder of an LNG booster pump. Comprising a compression cylinder, a compression piston connected with a piston rod is arranged in the compression cylinder, a liquid inlet and a liquid outlet are formed in the compression cylinder, the liquid outlet comprises a liquid outlet channel arranged in the side wall of the compression cylinder, the inner side of the liquid outlet channel is communicated with an inner cavity of the compression cylinder, the outer side of the liquid outlet channel extends to the end of the compression cylinder, and a taper hole is formed in the liquid outlet channel. A non-return core matched with the taper hole is movably arranged in the liquid outlet channel, a valve element is fixedly installed in the position, on the outer side of the non-return core, of the liquid outlet channel, a spring is installed between the valve element and the non-return core, and a fluid channel is formed in the valve element. The problem that sealing is not tight due to threaded connection of the liquid outlet valve and the compression cylinder in the prior art is solved, leakage points are reduced, and the leakage probability is reduced; the non-return core is matched with the taper hole, face-to-face sealing is achieved, the sealing effect is better, and the performance is more stable and reliable in the low-temperature and high-pressure environment.

Description

Technical field:

[0001] The utility model relates to the technical field of LNG boosting pumps, in particular to an integrated liquid outlet one-way valve structure of a cold-end compression cylinder of an LNG boosting pump. Background technology:

[0002] The existing LNG booster pump, whose structure is as shown in the patent application with publication number CN110185598A, discloses a vehicle-use low-temperature natural gas bottle built-in booster pump. When working, the compression cylinder is inserted into the LNG bottle, the hydraulic cylinder is located outside the LNG bottle, the cylinder piston in the hydraulic cylinder reciprocates under the push of the hydraulic oil, the cylinder piston drives the piston rod to reciprocate, and the piston rod drives the compression piston in the compression cylinder to reciprocate, so that the low-temperature liquid enters the compression cylinder through the liquid inlet valve, and then is discharged from the liquid outlet valve to the outside, so as to achieve the pressurization of the low-temperature liquid. Among them, the current liquid outlet valve on the compression cylinder has the following disadvantages when working for a long time under low temperature and high pressure environment: first, the current liquid outlet valve is a single part as a whole, connected to the compression cylinder by a threaded method, and has many leakage points and a high probability of leakage under low temperature and high pressure; second, the valve core generally adopts a spherical ball, which is in line contact when sealing, and the sealing effect is poor; third, the valve core is generally made of metal material, which has a short service life due to the influence of low temperature and high pressure, and is easy to cause LNG leakage, reducing the compression efficiency.

[0003] In summary, the liquid outlet sealing problem of the cold-end compression cylinder of the LNG booster pump has become a technical problem that urgently needs to be solved in the industry. Utility model content:

[0004] In order to make up for the deficiencies of the prior art, the utility model provides an integrated liquid outlet one-way valve structure for a compression cylinder at the cold end of an LNG boosting pump, which solves the problems of multiple leakage points, high leakage probability and poor sealing effect of previous liquid outlet valves.

[0005] The technical solution adopted by the utility model to solve the above technical problems is:

[0006] An integrated liquid outlet one-way valve structure for a cold-end compression cylinder of an LNG boosting pump comprises a compression cylinder, wherein a compression piston connected to a piston rod is arranged in the compression cylinder, a liquid inlet and a liquid outlet are arranged on the compression cylinder, the liquid outlet comprises a liquid outlet channel arranged in a side wall of the compression cylinder, the inner side of the liquid outlet channel is communicated with an inner cavity of the compression cylinder, the outer side of the liquid outlet channel extends to an end of the compression cylinder, a tapered hole is arranged in the liquid outlet channel, a check core matched with the tapered hole is movably arranged in the liquid outlet channel, a valve core is fixedly installed in the liquid outlet channel outside the check core, a spring is installed between the valve core and the check core, and a fluid channel is arranged in the valve core.

[0007] The liquid outlet channel comprises a longitudinal liquid outlet channel and a transverse liquid outlet channel which are connected to each other. The inner side of the longitudinal liquid outlet channel is connected to the inner cavity of the compression cylinder, and the outer side of the longitudinal liquid outlet channel extends to the side of the compression cylinder. A plug is provided at the outer port of the longitudinal liquid outlet channel, and the outer side of the transverse liquid outlet channel extends to the end of the compression cylinder. The tapered hole is provided at a position of the transverse liquid outlet channel close to the longitudinal liquid outlet channel.

[0008] The outer side of the longitudinal liquid outlet channel extends to the side of the compression cylinder, and a plug is provided at the outer port of the longitudinal liquid outlet channel.

[0009] The non-return core is provided with a conical surface which matches with the conical hole.

[0010] A plurality of liquid outlet grooves are arranged on the side wall of the non-return core.

[0011] The non-return core is made of fluorocarbon.

[0012] The non-return core is made of PCTFE material.

[0013] The outer surface of the valve core is threadedly connected to the inner surface of the transverse liquid outlet channel.

[0014] A spring groove is arranged at the inner end of the valve core, a spring is arranged in the spring groove, one end of the spring abuts against the bottom of the spring groove, and the other end abuts against the check core.

[0015] The inner end side wall of the valve core is provided with a plurality of liquid outlet holes.

[0016] A flange is provided on the outer end side of the valve core, and a copper gasket is provided between the flange and the end of the compression cylinder for sealing.

[0017] The utility model adopts the above scheme and has the following advantages:

[0018] By integrating the check core and the valve core in the horizontal liquid outlet channel of the compression cylinder, the liquid outlet valve and the compression cylinder are integrated into one, avoiding the problem of poor sealing caused by the previous threaded connection between the liquid outlet valve and the compression cylinder, reducing leakage points and lowering the chance of leakage; the check core cooperates with the tapered hole in the horizontal liquid outlet channel through the conical surface on it to achieve surface sealing and better sealing effect; the check core is made of PCTFE material, which is pressure-resistant and low-temperature-resistant, has strong corrosion resistance, and has more stable and reliable performance under low-temperature and high-pressure environments. Description of the drawings:

[0019] Figure 1 It is a cross-sectional structural schematic diagram of the utility model.

[0020] Figure 2 It is a three-dimensional structural schematic diagram of the non-return core of the utility model.

[0021] In the figure, 1, compression cylinder, 2, piston rod, 3, compression piston, 4, liquid inlet, 5, longitudinal liquid outlet channel, 6, transverse liquid outlet channel, 7, tapered hole, 8, check core, 9, valve core, 10, spring, 11, fluid channel, 12, plug, 13, tapered surface, 14, liquid outlet groove, 15, liquid outlet hole, 16, flange, 17, copper gasket. Specific implementation method:

[0022] In order to clearly illustrate the technical features of the present invention, the present invention is described in detail below through specific implementation methods and in conjunction with the accompanying drawings.

[0023] like Figure 1-2 As shown, an integrated liquid outlet one-way valve structure of a compression cylinder at the cold end of an LNG boosting pump comprises a compression cylinder 1, wherein a compression piston 3 connected to a piston rod 2 is arranged in the compression cylinder 1, a liquid inlet 4 and a liquid outlet are arranged on the compression cylinder 1, wherein the liquid outlet comprises a liquid outlet channel arranged in a side wall of the compression cylinder 1, wherein the inner side of the liquid outlet channel is communicated with the inner cavity of the compression cylinder 1, and the outer side of the liquid outlet channel extends to the end of the compression cylinder 1, wherein a tapered hole 7 is arranged in the liquid outlet channel, wherein a check core 8 cooperating with the tapered hole 7 is movably arranged in the liquid outlet channel, wherein a valve core 9 is fixedly installed in the liquid outlet channel outside the check core 8, wherein a spring 10 is installed between the valve core 9 and the check core 8, and wherein a fluid channel 11 is arranged in the valve core 9.

[0024] The liquid outlet channel includes a longitudinal liquid outlet channel 5 and a transverse liquid outlet channel 6 which are connected. The inner side of the longitudinal liquid outlet channel 5 is connected to the inner cavity of the compression cylinder 1. The outer side of the longitudinal liquid outlet channel 5 extends to the side of the compression cylinder 1. A plug 12 is provided at the outer port of the longitudinal liquid outlet channel 5 to facilitate the processing of the longitudinal liquid outlet channel 5. The outer side of the transverse liquid outlet channel 6 extends to the end of the compression cylinder 1. The tapered hole 7 is provided at a position of the transverse liquid outlet channel 6 close to the longitudinal liquid outlet channel 5.

[0025] The non-return core 8 is provided with a conical surface 13 which matches with the conical hole 7. The conical surface 13 matches with the conical hole 7 to achieve surface-to-surface sealing, and the sealing effect is better.

[0026] A plurality of liquid outlet grooves 14 are provided on the side wall of the non-return core 8 , and the liquid can flow out through the liquid outlet grooves 14 .

[0027] The non-return core 8 is made of fluorocarbon. Preferably, the non-return core 8 of the utility model is made of PCTFE material, which is resistant to pressure and low temperature, has strong anti-corrosion ability, and has more stable and reliable performance in low temperature and high pressure environment.

[0028] The outer surface of the valve core 9 is threadedly connected to the inner surface of the transverse liquid outlet channel 6 .

[0029] A spring groove is provided at the inner end of the valve core 9, and a spring 10 is provided in the spring groove. One end of the spring 10 abuts against the bottom of the spring groove, and the other end abuts against the check core 8. In a natural state, the check core 8 maintains contact and cooperation with the tapered hole 7 for sealing under the action of the spring 10.

[0030] The inner side wall of the valve core 9 is provided with a plurality of liquid outlet holes 15 , through which liquid can enter the fluid channel 11 .

[0031] A flange 16 is provided at the outer end side of the valve core 9, and a copper gasket 17 is provided between the flange 16 and the end of the compression cylinder 1 for sealing, which can improve the sealing effect and avoid leakage.

[0032] Working principle:

[0033] When liquid is introduced, the piston rod 2 drives the compression piston 3 to move to the left, and the liquid enters the inner cavity of the compression cylinder 1 from the liquid inlet 4. Under the action of the spring 10, the conical surface 13 of the check core 8 contacts and seals with the conical hole 7, closing the lateral liquid outlet channel 6, which can achieve a good check effect.

[0034] When the liquid is discharged, the piston rod 2 drives the compression piston 3 to move to the right to pressurize the liquid. After the liquid pressure continues to increase, it pushes the check core 8 to move and compresses the spring 10, so that a gap is generated between the conical surface 13 of the check core 8 and the conical hole 7. The liquid can then pass through the liquid outlet groove 14 and the liquid outlet hole 15 into the fluid channel 11 and be discharged outward.

[0035] The above-mentioned specific implementation manner cannot be used as a limitation on the protection scope of the present utility model. For those skilled in the art, any replacement, improvement or change made to the implementation manner of the present utility model falls within the protection scope of the present utility model.

[0036] The matters not described in detail in the present invention are all known technologies to those skilled in the art.

Claims

1. An integrated liquid outlet check valve structure for a cold end compression cylinder of an LNG booster pump, comprising a compression cylinder, a compression piston connected to a piston rod is arranged in the compression cylinder, and a liquid inlet and a liquid outlet are arranged on the compression cylinder, characterized in that: The liquid outlet includes a liquid outlet channel arranged in the side wall of the compression cylinder, the inner side of the liquid outlet channel is connected with the inner cavity of the compression cylinder, the outer side of the liquid outlet channel extends to the end of the compression cylinder, a tapered hole is arranged in the liquid outlet channel, a check core matched with the tapered hole is movably arranged in the liquid outlet channel, a valve core is fixedly installed in the liquid outlet channel outside the check core, a spring is installed between the valve core and the check core, and a fluid channel is arranged in the valve core.

2. According to claim 1, the structure of an integrated liquid outlet check valve for the cold end compression cylinder of an LNG boosting pump is characterized in that: The liquid outlet channel comprises a longitudinal liquid outlet channel and a transverse liquid outlet channel which are connected to each other. The inner side of the longitudinal liquid outlet channel is connected to the inner cavity of the compression cylinder, and the outer side of the longitudinal liquid outlet channel extends to the side of the compression cylinder. A plug is provided at the outer port of the longitudinal liquid outlet channel, and the outer side of the transverse liquid outlet channel extends to the end of the compression cylinder. The tapered hole is provided at a position of the transverse liquid outlet channel close to the longitudinal liquid outlet channel.

3. The LNG booster pump cold end compression cylinder integrated liquid outlet check valve structure according to claim 1, characterized in that: The non-return core is provided with a conical surface which matches with the conical hole.

4. The LNG booster pump cold end compression cylinder integrated liquid outlet check valve structure according to claim 1, characterized in that: A plurality of liquid outlet grooves are arranged on the side wall of the non-return core.

5. The LNG booster pump cold end compression cylinder integrated liquid outlet check valve structure according to claim 1, characterized in that: The non-return core is made of fluorocarbon.

6. The structure of an integrated liquid outlet check valve for a cold end compression cylinder of an LNG booster pump according to claim 5, characterized in that: The non-return core is made of PCTFE material.

7. The LNG booster pump cold end compression cylinder integrated liquid outlet check valve structure according to claim 2, characterized in that: The outer surface of the valve core is threadedly connected to the inner surface of the transverse liquid outlet channel.

8. The LNG booster pump cold end compression cylinder integrated liquid outlet check valve structure according to claim 1, characterized in that: A spring groove is arranged at the inner end of the valve core, a spring is arranged in the spring groove, one end of the spring abuts against the bottom of the spring groove, and the other end abuts against the check core.

9. The LNG booster pump cold end compression cylinder integrated liquid outlet check valve structure according to claim 1, characterized in that: The inner end side wall of the valve core is provided with a plurality of liquid outlet holes.

10. The LNG booster pump cold end compression cylinder integrated liquid outlet check valve structure according to claim 1, characterized in that: A flange is provided on the outer end side of the valve core, and a copper gasket is provided between the flange and the end of the compression cylinder for sealing.

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