Wide temperature range reciprocating piston pump

Abstract

The utility model relates to a kind of wide temperature range reciprocating plunger pump, belong to plunger pump technical field.The material with small thermal expansion coefficient, strong toughness under low temperature environment, strong corrosion resistance is selected to do core component (such as plunger, stuffing box, pump body, valve assembly etc.), the sealing structure between plunger and stuffing box, sealing material are also adjusted, the dynamic sealing reliable in wide temperature range is guaranteed, can be stably operated in the wide temperature range of-55 ℃ to 300 ℃;It is also through the circulating heat dissipation loop that power end, heat exchanger and circulating motor are formed, realize the heat dissipation and low temperature preheating of core moving component, ensure thermal stability.Make the reciprocating plunger pump of the utility model can be stably operated in the wide temperature range of-55 ℃ to 300 ℃.

Description

Technical Field

[0001] This utility model belongs to the field of plunger pump technology and relates to a wide temperature range reciprocating plunger pump. Background Technology

[0002] Reciprocating piston pumps, as a type of highly efficient and reliable positive displacement pump, play an indispensable role in industrial production. They rely on the reciprocating motion of the piston within the pump cylinder, causing the volume of the working chamber to periodically increase and decrease, thereby achieving precise liquid delivery. These pumps have many outstanding advantages: excellent self-priming performance, capable of automatically drawing liquid into the pump without the need for an additional priming device; extremely wide adaptability to a wide range of media, effectively delivering both low-viscosity and high-viscosity liquids, as well as liquids containing certain impurities; and high output pressure, meeting the demands of some processes with stringent pressure requirements.

[0003] However, most reciprocating piston pumps commonly found on the market are only suitable for normal temperature conditions. When faced with extreme environments with a wide temperature range of -55℃ to 300℃, they are difficult to operate stably. There are many complex reasons behind this.

[0004] From a materials perspective, in low-temperature environments, the toughness of ordinary metal materials decreases significantly, becoming brittle and easily broken. When reciprocating piston pumps operate in such low temperatures, critical components such as the pistons and pump cylinders are highly susceptible to fracture and damage under the enormous stress generated by the reciprocating motion. For example, some commonly used alloy steel materials may experience a drop in impact toughness to a fraction of their normal temperature performance below -55°C, making them unable to withstand the impact loads of normal piston pump operation. Conversely, in high-temperature environments, the strength of materials decreases significantly, and creep also occurs. Rubber seals, for instance, rapidly age, harden, and lose elasticity at 300°C, leading to a sharp decline in sealing performance, liquid leakage, and disruption to the pump's normal operation.

[0005] From a lubrication perspective, low temperatures significantly increase the viscosity of lubricating oil, reducing its fluidity. This prevents the lubricating oil from reaching the friction surfaces in a timely and sufficient manner to form an effective lubricating film between the plunger, pump cylinder, bearings, and other moving parts, thus exacerbating wear between components and shortening the pump's lifespan. Conversely, high temperatures decrease the viscosity of lubricating oil, making it more prone to evaporation and oxidation. This also fails to provide adequate lubrication and protection for moving parts, leading to increased wear and even serious malfunctions such as seizure.

[0006] Furthermore, the physical properties of the medium inside the pump can change significantly over a wide temperature range, such as viscosity and density. These changes directly affect the pump's performance parameters, such as flow rate and pressure, making it difficult for the pump to operate stably under the set conditions and meet the requirements of the production process.

[0007] Therefore, in order to address these shortcomings in existing technologies, it is particularly urgent to develop a new type of reciprocating piston pump that can adapt to a wide temperature range. Utility Model Content

[0008] In view of this, the purpose of this utility model is to provide a wide temperature range reciprocating plunger pump that can operate stably within a wide temperature range.

[0009] To achieve the above objectives, this utility model provides the following technical solution: A wide-temperature-range reciprocating plunger pump includes a base frame, and a power motor assembly, a power end, a heat exchanger, a hydraulic end, and a circulating motor assembly mounted on the base frame. The power motor assembly is connected to the power end and provides power to the power end. The hydraulic end is fixed to the side of the power end. The oil outlet of the power end is connected to the first oil port of the heat exchanger, the second oil port of the heat exchanger is connected to the oil inlet of the circulating motor assembly, and the oil outlet of the circulating motor assembly is connected back to the oil inlet of the power end. The power end, the heat exchanger, and the circulating motor assembly together form a heat dissipation circuit. A stuffing box assembly is integrated into the mounting cavity of the power end. The stuffing box assembly includes a stuffing box body, and a plunger is provided inside the stuffing box body; an adjusting nut, a guide sleeve and packing are sequentially sleeved between the stuffing box body and the plunger, and spacers are provided between the packings to enhance the support and sealing effect.

[0010] Optionally, the adjusting nut is located at the end of the stuffing box and is tightened by screwing to adjust its preload so that it fits the plunger better.

[0011] Optionally, an O-ring is provided at one end of the stuffing box that mates with the mounting cavity of the power end to achieve a static seal.

[0012] Optionally, the hydraulic end includes a pump body and a pressure strip disposed on the top of the pump body, and the pump body is further provided with a valve assembly; the pressure strip is used to seal the valve assembly.

[0013] Optionally, the pressure bar is fixed to the top of the pump body by short bolts and nuts.

[0014] Optionally, the pump body is fixed to the side of the power end by a through bolt and a nut that matches the bolt.

[0015] Optionally, the pump body is a 316L stainless steel pump body, the pressure bar is a 316L stainless steel pressure bar, and the valve assembly is a 2Cr13 stainless steel valve assembly.

[0016] Optionally, the plunger and the stuffing box are respectively a 2Cr13 stainless steel plunger and a 2Cr13 stainless steel stuffing box.

[0017] Optionally, the plunger surface is further provided with a tungsten carbide coating; the spacer is a polytetrafluoroethylene spacer.

[0018] Optionally, the power unit is connected to the heat exchanger via a hose, and the circulating motor assembly is connected to the power unit via a hose.

[0019] The beneficial effects of this utility model are as follows: This invention achieves long-term stable operation of a reciprocating plunger pump within an extreme temperature range of -55℃ to 300℃ through material selection, sealing structure optimization, and circulating heat exchange design. Its technical advantages are mainly reflected in the following aspects: Firstly, regarding wide temperature range adaptability, core components (such as plungers, stuffing boxes, pump bodies, and valve assemblies) are made of materials with low coefficients of thermal expansion, high toughness at low temperatures, and strong corrosion resistance. For example, 2Cr13 is used for the plungers and stuffing boxes, and 316L is used for the pump body. This significantly reduces the risk of dimensional deformation caused by drastic temperature changes, thereby avoiding functional failures caused by high-temperature jamming or low-temperature loosening. Simultaneously, the packing and spacers are made of polytetrafluoroethylene (PTFE) and its composite materials, which combine high and low temperature resistance, self-lubrication, and creep resistance, ensuring the sealing system maintains elasticity and tightness across the entire temperature range and effectively preventing media leakage.

[0020] Secondly, this invention improves the sealing reliability and maintainability of the system through multi-stage sealing and an adjustable preload structure. The stuffing box incorporates a combination of guide sleeve, packing, and spacers, and the sealing pressure is dynamically adjusted via an adjusting nut. This compensates for changes in preload caused by thermal expansion and contraction of the material, and also extends the lifespan of the seals. An O-ring is used in the static sealing section to further block leakage paths. This dynamic and static combined, adjustable sealing design allows the pump to maintain stable sealing performance even under long-term temperature cycling conditions.

[0021] In addition, the independently designed closed-loop cooling system (power end - heat exchanger - circulating motor assembly) realizes active thermal management, which can not only effectively dissipate heat during high-temperature operation, but also prevent lubricant failure and component overheating.

[0022] Through the above-mentioned features, this invention enables the plunger pump to maintain high reliability, long lifespan, and low maintenance requirements even under extreme temperature differences, making it applicable to multiple technical fields.

[0023] Other advantages, objectives, and features of this invention will be set forth in part in the description which follows, and in part will be apparent to those skilled in the art from the following examination and study, or may be learned from practice of this invention. The objectives and other advantages of this invention can be realized and obtained through the following description. Attached Figure Description

[0024] To make the objectives, technical solutions, and advantages of this utility model clearer, the preferred embodiments of this utility model will be described in detail below with reference to the accompanying drawings, wherein: Figure 1 This is a top view of a reciprocating piston pump; Figure 2 This is a front view of a reciprocating piston pump; Figure 3 This is a side view of a reciprocating piston pump; Figure 4 This is a cross-sectional view of the stuffing gland assembly; Figure 5 This is a side view of the stuffing gland assembly; Figure 6 This is a cross-sectional view of the hydraulic end.

[0025] Figure label: 1. Base frame, 2. Power motor assembly, 3. Power end, 4. Heat exchanger, 5. Hydraulic end, 6. Circulation motor assembly, 10. Piston, 11. Adjusting nut, 12. Stuffing box, 13. Guide sleeve, 14. Packing, 15. Spacer, 16. O-ring, 21. Pump body, 22. Pressure bar, 23. Nut, 24. Short bolt, 25. Valve assembly, 26. Long bolt. Detailed Implementation

[0026] The following specific examples illustrate the implementation of this utility model. Those skilled in the art can easily understand other advantages and effects of this utility model from the content disclosed in this specification. This utility model can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of this utility model. It should be noted that the illustrations provided in the following embodiments are only schematic representations of the basic concept of this utility model. Unless otherwise specified, the following embodiments and features in the embodiments can be combined with each other.

[0027] The accompanying drawings are for illustrative purposes only and are schematic diagrams, not actual pictures. They should not be construed as limiting the present invention. To better illustrate the embodiments of the present invention, some parts in the drawings may be omitted, enlarged, or reduced, and do not represent the actual product dimensions. It is understandable to those skilled in the art that some well-known structures and their descriptions may be omitted in the drawings.

[0028] In the accompanying drawings of this utility model, the same or similar reference numerals correspond to the same or similar components. In the description of this utility model, it should be understood that if terms such as "upper," "lower," "left," "right," "front," and "rear" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, they are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, the terms used to describe positional relationships in the drawings are only for illustrative purposes and should not be construed as limiting this utility model. For those skilled in the art, the specific meaning of the above terms can be understood according to the specific circumstances.

[0029] Please see Figures 1-6 This is a wide-temperature-range reciprocating plunger pump, comprising a base frame 1, which serves as the support structure for the entire device. The base frame 1 houses a power motor assembly 2, a power end 3, a heat exchanger 4, a hydraulic end 5, and a circulating motor assembly 6. The power motor assembly 2 is connected to the power end 3 and provides power to it. The hydraulic end 5 is fixed to the side of the power end 3. The oil outlet of the power end 3 is connected to the first oil port of the heat exchanger 4 via a hose. The second oil port of the heat exchanger 4 is connected to the oil inlet of the circulating motor assembly 6. The oil outlet of the circulating motor assembly 6 is connected back to the oil inlet of the power end 3 via a hose. The power end 3, heat exchanger 4, and circulating motor assembly 6 together form a heat dissipation circuit. A stuffing box assembly is integrated into the mounting cavity of the power end 3.

[0030] The heat dissipation circuit, consisting of the power unit 3, heat exchanger 4, and circulating motor assembly 6, uses the circulating motor assembly 6 as the power source to drive the heat transfer oil to flow continuously in a closed pipeline. During operation, the oil first flows out from the outlet port of the power unit 3, carrying the heat accumulated inside the power unit 3 due to reciprocating motion, friction, and medium transfer. Then, the hot oil enters the heat exchanger 4, where it undergoes convective heat exchange with external cooling air or cooling medium, effectively dissipating heat to the outside. The cooled oil is then pressurized by the circulating motor assembly and returned to the inlet port of the power unit 3, completing one cycle. In the high-temperature stage, this heat dissipation circuit prevents overheating of the power unit 3 and maintains stable lubricating oil performance through continuous circulation and heat dissipation. In the low-temperature stage, the circulating oil gradually absorbs the cold energy inside the power unit 3 and, when necessary, introduces an external heat source through the heat exchanger 4 or utilizes the heat generated by the motor itself to slowly raise the system temperature, improving low-temperature start-up conditions and preventing cold brittleness and lubrication failure. This provides a continuous and stable thermal environment for the core moving components of the plunger pump over a wide temperature range.

[0031] The stuffing box assembly includes a stuffing box body 12, which serves as the main structure. A plunger 10 is installed inside the stuffing box body 12. An adjusting nut 11, a guide sleeve 13, and packing 14 are sequentially installed between the stuffing box body 12 and the plunger 10. The guide sleeve 13 guides the movement of the plunger 10; the packing 14 provides a seal to prevent media leakage; and spacers 15 are located between the packing 14 to enhance their support and sealing effect. The adjusting nut 11 is located at one end of the stuffing box body 12 and is tightened by turning to compress the packing 14, adjusting its preload to better fit the plunger 10. An O-ring 16 is provided at the end of the stuffing box body 12 that mates with the mounting cavity of the power end 3 to achieve a static seal.

[0032] The hydraulic end 5 includes a pump body 21 and a pressure strip 22 disposed on the top of the pump body 21. The pressure strip 22 is fixedly locked to the top of the pump body 21 by short bolts 24 and nuts 23. The pump body 21 is fixedly locked to the side of the power end 3 by long bolts 26 that pass through it and nuts 23 that cooperate with the long bolts 26.

[0033] The pump body 21 also contains a valve assembly 25. When the volume inside the working chamber increases, creating low pressure, the inlet valve of the valve assembly 25 is pushed open by the external liquid, allowing it to enter the pump body 21. The outlet valve of the valve assembly 25 is closed due to the pressure of the liquid inside the pipe. When the liquid is squeezed, increasing the pressure, it pushes open the outlet valve and is forced into the discharge pipe, while the suction valve closes. The valve assembly 25 is sealed by a pressure strip 22.

[0034] Furthermore, the pump body 21 and pressure bar 22 are made of 316L stainless steel, which has excellent corrosion resistance and mechanical properties. The plunger 10, stuffing box 12, and valve assembly 25 are made of 2Cr13 stainless steel, which has good high and low temperature performance, high hardness, good corrosion resistance, low coefficient of thermal expansion, and strong toughness at low temperatures. The plunger 10 is also coated with tungsten carbide to increase wear resistance; the spacer 15 is made of polytetrafluoroethylene.

[0035] This utility model of a wide-temperature-range reciprocating plunger pump uses materials with low thermal expansion coefficient, high toughness at low temperatures, and strong corrosion resistance as the main core components (such as plunger 10, packing 14, pump body 21, valve assembly 25, etc.) to adapt to the operating requirements within a wide temperature range. The sealing structure and sealing material between plunger 10 and packing 14 have also been adjusted. By adjusting the dynamic seal of nut 11 and the static seal of O-ring 16, the pump can maintain stable sealing performance and wear resistance under long-term temperature cycling conditions, enabling the entire device to operate stably within a wide temperature range from -55℃ to 300℃.

[0036] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of this utility model and are not intended to limit it. Although this utility model has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solution of this utility model without departing from the spirit and scope of this technical solution, and all such modifications or substitutions should be covered within the scope of the claims of this utility model.

Claims

1. A wide-temperature-range reciprocating plunger pump, characterized in that: The device includes a base frame (1), and a power motor assembly (2), a power end (3), a heat exchanger (4), a hydraulic end (5), and a circulating motor assembly (6) mounted on the base frame (1). The power motor assembly (2) is connected to the power end (3) and provides power to the power end (3). The hydraulic end (5) is fixed to the side of the power end (3). The oil outlet of the power end (3) is connected to the first oil port of the heat exchanger (4), the second oil port of the heat exchanger (4) is connected to the oil inlet of the circulating motor assembly (6), and the oil outlet of the circulating motor assembly (6) is connected back to the oil inlet of the power end (3). The power end (3), the heat exchanger (4), and the circulating motor assembly (6) together form a heat dissipation circuit. A packing (14) assembly is integrated into the mounting cavity of the power end (3). The packing (14) assembly includes a packing body (12), inside which is a plunger (10); between the packing body (12) and the plunger (10), an adjusting nut (11), a guide sleeve (13) and packing (14) are sequentially fitted, and between the packing body (12) and the plunger (10), there are spacers (15) between the packings (14) to enhance the support and sealing effect.

2. The wide temperature range reciprocating plunger pump according to claim 1, characterized in that: The adjusting nut (11) is located on the end side of the stuffing box (12). It is tightened by screwing to press the packing (14) to adjust its preload so that it can fit the plunger (10) better.

3. The wide temperature range reciprocating plunger pump according to claim 1, characterized in that: The stuffing box (12) is provided with an O-ring (16) at one end that mates with the mounting cavity of the power end (3) to achieve static sealing.

4. The wide temperature range reciprocating plunger pump according to claim 1, characterized in that: The hydraulic end (5) includes a pump body (21) and a pressure strip (22) disposed on the top of the pump body (21). A valve assembly (25) is also provided inside the pump body (21). The pressure strip (22) is used to seal the valve assembly (25).

5. The wide temperature range reciprocating plunger pump according to claim 4, characterized in that: The pressure bar (22) is fixed to the top of the pump body (21) by short bolts (24) and nuts (23).

6. The wide temperature range reciprocating plunger pump according to claim 4, characterized in that: The pump body (21) is fixed to the side of the power end (3) by a through bolt (26) and a nut (23) that matches the bolt (26).

7. The wide temperature range reciprocating plunger pump according to claim 4, characterized in that: The pump body (21) is a 316L stainless steel pump body (21), the pressure bar (22) is a 316L stainless steel pressure bar (22), and the valve assembly (25) is a 2Cr13 stainless steel valve assembly (25).

8. The wide temperature range reciprocating plunger pump according to claim 1, characterized in that: The plunger (10) and the stuffing box (12) are respectively 2Cr13 stainless steel plunger (10) and 2Cr13 stainless steel stuffing box (12).

9. The wide temperature range reciprocating plunger pump according to claim 1, characterized in that: The plunger (10) is also provided with a tungsten carbide coating; the spacer (15) is a polytetrafluoroethylene spacer (15).

10. The wide temperature range reciprocating plunger pump according to claim 1, characterized in that: The power end (3) is connected to the heat exchanger (4) via a hose, and the circulating motor assembly (6) is connected to the power end (3) via a hose.

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