Cross hole structure of high-pressure pump flow channel
By designing the maximum transition rounded corners in the working chamber and plunger channel of the high-pressure pump, the problem of low fatigue resistance at the intersection of the medium flow channel and the plunger channel is solved, and the effect of improving the fatigue resistance of the pump body and extending the service life is achieved.
Patent Information
- Application Number
- CN202422032839.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-08-21
- Publication Date
- 2025-06-03
- Estimated Expiration
- 2034-08-21
AI Technical Summary
In existing high-pressure pumps, the fatigue resistance strength between the medium flow channel and the plunger channel is low, resulting in material fatigue cracks and pump body failure.
A high-pressure pump flow channel cross-hole structure is designed to eliminate sharp corners and reduce stress concentration by forming a maximum first transition round corner at the top and bottom of the working chamber and forming a maximum second transition round corner at the end where the plunger channel runs across the working chamber.
It effectively slows down stress concentration in sharp corners, improves the fatigue resistance of the pump body, extends the service life of the pump body, and reduces the sensitivity of the material to alternating loads.
Smart Images
Figure CN222936918U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of high-pressure pumps, in particular to a cross-hole structure of a high-pressure pump flow channel. Background Art
[0002] During the production process, pumps that can generate high pressure or ultra-high pressure are mostly positive displacement pumps, such as gear pumps, rotor pumps, and plunger pumps. They have a common feature: the outlet pressure of the pump is fluctuating, and there is a certain pulse amplitude and frequency.
[0003] Please refer to the attached Figure 1 and the attached Figure 2 , the high-pressure pump of the prior art includes a pump body 1 and a plunger. A medium flow channel 11 and a plunger channel 12 are formed in the pump body 1. A working chamber 13 with a diameter D in the middle of the medium flow channel 11 is vertically crossed with the plunger channel 12. The medium flows through the medium flow channel 11 through a check valve, and the plunger reciprocates in the plunger channel 12.
[0004] When the plunger is pushed, the check valve closes. At this time, the medium in the working chamber 13 is compressed to generate high-pressure fluid and flows out through the medium outlet, completing a working cycle. The flow direction of the medium and the movement direction of the plunger are as shown by the arrows in Figure 2 . As the plunger continuously reciprocates, the medium will continuously enter the working chamber 13. At this time, the pressure borne in the pump body 1 is an alternating load, that is, the absolute pressure of periodic change is 0.1 MPa (standard atmospheric pressure) and Pmax (the maximum working pressure setting value, which can be set according to actual process requirements). Correspondingly, the stress and strain of the pump body material will also change periodically.
[0005] For dimensional considerations, the outermost prime line of the outer diameter of the plunger channel 12 is close to coinciding with the upper opening of the working chamber 13, so that there is a distance of ΔX between the axial center line 121 of the plunger channel 12 and the radial center line 131 of the working chamber 13; at the same time, chamfers 14 are formed at the top and bottom of the working chamber 13, and sharp corners are likely to be generated at the junction of the chamfer 14 and the medium flow channel 11, and sharp corner mutations are also likely to be generated at the intersection of the medium flow channel 11 and the plunger channel 12.
[0006] Since the stress in the pump body 1 is mainly concentrated and distributed at the sharp corners and sharp corner mutation parts formed by the chamfer 14 of the working chamber 13, the excessive concentrated stress will cause the material to generate fatigue cracks, and the alternating load will accelerate the rapid expansion of the fatigue cracks. When the cracks expand to a certain extent, the strength of the pump body 1 will be severely weakened and unable to meet the use requirements, reducing the fatigue resistance of the alloy steel material of the pump body 1 and resulting in the failure of the pump body 1. Therefore, it is necessary to provide a cross-hole structure of a high-pressure pump flow channel that can solve the problem of low fatigue strength at the intersection of the medium flow channel and the plunger channel in the prior art. Summary of the Invention
[0007] The purpose of the present utility model is to provide a cross-hole structure for the flow channel of a high-pressure pump, which can solve the problem of low anti-fatigue strength at the intersection of the medium flow channel and the plunger channel in the prior art.
[0008] The present utility model is implemented as follows:
[0009] A cross-hole structure for the flow channel of a high-pressure pump includes a pump body. A medium flow channel and a plunger channel are formed in the pump body, and the plunger channel is vertically and penetratingly connected to the working cavity in the medium flow channel. The top and bottom of the working cavity are smoothly transitionally connected to the medium flow channel, and the middle part of the side end of the working cavity is smoothly transitionally connected to the plunger channel.
[0010] First transition fillets are respectively formed along the circumferential direction at the top and bottom of the working cavity, so that the top and bottom of the working cavity are smoothly transitionally connected to the medium flow channel through the first transition fillets.
[0011] A second transition fillet is formed along the circumferential direction at one end of the plunger channel where it intersects with the working cavity, and the second transition fillet is smoothly transitionally connected to the first transition fillets at the top and bottom of the working cavity.
[0012] The axial center line of the working cavity coincides with the center line of the plunger channel, so that the first transition fillets at the top and bottom of the working cavity are symmetrically connected to the top and bottom of the second transition fillet.
[0013] The inner walls of the medium flow channel, the working cavity, the first transition fillet and the second transition fillet are smooth surfaces, and the roughness of the smooth surface does not exceed Ra0.4.
[0014] A nitrided layer is formed on the inner walls of the medium flow channel, the working cavity and the first transition fillet.
[0015] Compared with the prior art, the present utility model has the following beneficial effects:
[0016] 1. Since the present utility model is provided with a maximized first transition fillet, the first transition fillet makes the top and bottom of the working cavity smoothly transitionally connected to the medium flow channel, eliminating the sharp corners between the medium flow channel and the working cavity, thereby slowing down the stress concentration at the sharp corner parts and the material fatigue cracking caused by the stress concentration. Furthermore, the high-strength performance of the pump body made of alloy steel can be fully exerted, the anti-fatigue performance of the pump body is improved, and the service life of the pump body is prolonged.
[0017] 2. Since the present utility model is provided with a maximized second transition fillet, the second transition fillet makes the working cavity smoothly transitionally connected to the plunger channel, eliminating the sharp corner mutation at the intersection of the working cavity and the plunger channel, thereby slowing down the stress concentration at the sharp corner mutation parts and the material fatigue cracking caused by the stress concentration. The high-strength performance of the pump body made of alloy steel can be fully exerted, the anti-fatigue performance of the pump body is improved, and the service life of the pump body is prolonged.
[0018] 3. Since the present utility model adopts a medium flow channel, a working chamber, a first transition fillet and a second transition fillet with smooth surfaces, it can reduce the sensitivity of the pump body steel material to the action of alternating loads. At the same time, since the present utility model adopts a medium flow channel, a working chamber and a first transition fillet with a nitrided layer, it can further improve the surface strength of the internal flow channel of the pump body, thereby extending the service life of the pump body. BRIEF DESCRIPTION OF THE DRAWINGS
[0019] Figure 1 is the front view of the cross-hole structure of the flow channel of the prior art high-pressure pump;
[0020] Figure 2 is the A-A cross-sectional view of the cross-hole structure of the flow channel of the prior art high-pressure pump;
[0021] Figure 3 is the front view of the cross-hole structure of the flow channel of the high-pressure pump of the present utility model;
[0022] Figure 4 is the B-B cross-sectional view of the cross-hole structure of the flow channel of the high-pressure pump of the present utility model.
[0023] In the figure, 1 is the pump body, 11 is the medium flow channel, 12 is the plunger channel, 121 is the axial center line, 13 is the working chamber, 131 is the radial center line, 14 is the chamfer, 15 is the first transition fillet, 16 is the second transition fillet, and 17 is the nitrided layer. DETAILED DESCRIPTION OF THE EMBODIMENTS
[0024] The present utility model will be further described below with reference to the accompanying drawings and specific embodiments.
[0025] Please refer to the attached Figure 3 and the attached Figure 4 , a cross-hole structure of a high-pressure pump flow channel, including a pump body 1, a medium flow channel 11 and a plunger channel 12 are formed in the pump body 1, and the plunger channel 12 is vertically and communicatively connected to a working chamber 13 in the medium flow channel 11; the top and bottom of the working chamber 13 are smoothly and transitionally connected to the medium flow channel 11, and the middle part of the side end of the working chamber 13 is smoothly and transitionally connected to the plunger channel 12.
[0026] Through the smooth and transitional connection between the working chamber 13 and the medium flow channel 11, the sharp corners between the top and bottom of the working chamber 13 and the medium flow channel 11 are eliminated, and the stress concentration at the top and bottom of the working chamber 13 is alleviated. At the same time, through the smooth and transitional connection between the plunger channel 12 and the working chamber 13, the sharp corner mutation at the intersection of the plunger channel 12 and the working chamber 13 is eliminated, thereby alleviating the stress concentration at the intersection of the plunger channel 12 and the working chamber 13.
[0027] At the top and bottom of the working chamber 13, first transition rounded corners 15 are respectively formed along the circumferential direction, so that the top and bottom of the working chamber 13 are smoothly connected to the medium flow channel 11 through the first transition rounded corners 15.
[0028] Preferably, the first transition rounded corners 15 should be maximized as much as possible to ensure a smooth transition connection between the working chamber 13 and the medium flow channel 11, thereby effectively reducing the generation of sharp corners, and further reducing the stress concentration and the decrease in material fatigue resistance caused by the sharp corners.
[0029] At one end where the plunger channel 12 intersects with the working chamber 13, second transition rounded corners 16 are formed along the circumferential direction, and the second transition rounded corners 16 are smoothly connected to the first transition rounded corners 15 at the top and bottom of the working chamber 13.
[0030] Preferably, the second transition rounded corners 16 should be maximized as much as possible to ensure a smooth transition connection between the first transition rounded corners 15 and the second transition rounded corners 16, thereby effectively reducing the generation of sharp corner mutations, and further reducing the stress concentration and the decrease in material fatigue resistance caused by the sharp corner mutations.
[0031] The axial center line of the working chamber 13 coincides with the center line of the plunger channel 12, so that the first transition rounded corners 15 at the top and bottom of the working chamber 13 are symmetrically connected to the top and bottom of the second transition rounded corners 16.
[0032] Under the condition that the manufacturing process can achieve, the axial center line of the working chamber 13 is made to coincide with the center line of the plunger channel 12 as much as possible, that is, the distance of ΔX approaches 0 infinitely, so as to ensure a symmetric and smooth transition connection between the first transition rounded corners 15 and the second transition rounded corners 16 at the top and bottom of the working chamber 13, avoid the generation of sharp corner mutations, and further avoid the problems of stress concentration and material fatigue cracking at the sharp corner mutation positions under the action of alternating loads.
[0033] The inner walls of the medium flow channel 11, the working chamber 13, the first transition rounded corners 15 and the second transition rounded corners 16 are smooth surfaces, and the roughness of the smooth surfaces does not exceed Ra0.4.
[0034] The processing quality of the material surface has a great influence on its fatigue resistance. For components with higher requirements for fatigue strength, through machining with a lower surface roughness Ra0.4 or even lower surface roughness, good material strength and fatigue resistance can be ensured under the action of alternating loads.
[0035] Nitriding layers 17 are formed on the inner walls of the medium flow channel 11, the working chamber 13 and the first transition rounded corners 15.
[0036] After nitriding treatment, the surface layer strength of the inner walls of the dielectric flow channel 11 and the first transition fillet 15 can be effectively improved through the nitrided layer 17, thus helping to reduce the problem of the decline in the anti-fatigue performance of the material. Nitriding treatment is a conventional means of material surface strengthening in the art, and the process of nitriding treatment will not be elaborated here.
[0037] Please refer to the appendix Figure 3 and the appendix Figure 4 , the working principle of the present utility model is:
[0038] According to the sizes of the dielectric flow channel 11 and the working chamber 13, the first transition fillet 15 is maximized to prevent sharp corners from being generated at the junction position between the dielectric flow channel 11 and the working chamber 13. According to the sizes of the plunger channel 12 and the working chamber 13, the second transition fillet 16 is maximized to prevent sharp corner mutations from occurring at the intersection part between the dielectric flow channel 11 and the plunger channel 12, thereby effectively reducing the high stress concentration at the sharp corner part and the material fatigue cracks caused by the high stress concentration.
[0039] Meanwhile, the distance of ΔX approaches 0 infinitely, further ensuring that the intersection part between the dielectric flow channel 11 and the plunger channel 12 can have a smooth transition, and further reducing the problem of the decline in anti-fatigue performance caused by high stress concentration.
[0040] The above is only the preferred embodiment of the present utility model and is not used to limit the protection scope of the present utility model. Therefore, any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present utility model shall be included within the protection scope of the present utility model.
Claims
1. A high-pressure pump flow channel cross hole structure, comprising a pump body (1), wherein a medium flow channel (11) and a plunger channel (12) are formed in the pump body (1), and the plunger channel (12) is vertically connected to a working chamber (13) in the medium flow channel (11); wherein: The top and bottom of the working chamber (13) are smoothly connected to the medium flow channel (11), and the middle of the side end of the working chamber (13) is smoothly connected to the plunger channel (12).
2. The high-pressure pump flow channel cross hole structure according to claim 1 is characterized in that: The top and bottom of the working chamber (13) are respectively formed with first transition fillets (15) along the circumferential direction, so that the top and bottom of the working chamber (13) are smoothly transitionally connected to the medium flow channel (11) through the first transition fillets (15).
3. The high-pressure pump flow channel cross hole structure according to claim 2 is characterized in that: A second transition fillet (16) is formed along the circumferential direction at one end of the plunger channel (12) intersecting the working chamber (13); the second transition fillet (16) is smoothly connected to the first transition fillets (15) at the top and bottom of the working chamber (13).
4. The high-pressure pump flow channel cross hole structure according to claim 3 is characterized by: The axial centerline of the working chamber (13) coincides with the centerline of the plunger passage (12), so that the first transition fillets (15) at the top and bottom of the working chamber (13) are symmetrically connected to the top and bottom of the second transition fillets (16).
5. The high-pressure pump flow channel cross hole structure according to claim 3 or 4, characterized in that: The inner walls of the medium flow channel (11), the working chamber (13), the first transition fillet (15) and the second transition fillet (16) are smooth surfaces, and the roughness of the smooth surface does not exceed Ra0.
4.
6. The high-pressure pump flow channel cross hole structure according to any one of claims 1 to 4, characterized in that: A nitride layer (17) is formed on the inner walls of the medium flow channel (11), the working chamber (13) and the first transition fillet (15).