JPH09217677A - Valve seat for plunger pump - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a valve seat the shape of which does not cause an erosion phenomenon. SOLUTION: An elastic surface 27 of a surface of an elastic body and a non-elastic surface 35 of a surface of a metallic body are formed as valve seat surfaces of a valve seat 21 of a surface symmetrical valve structural body arranged in a channel of high pressure pulsating fluid produced by a plunger reciprocating in a cylinder and used, a channel 22 orthogonal with the valve seat surfaces is formed on a central side of the valve seat 21, a turbulence generating part on a corner of the valve seat 21 forming the channel 22 is cut out and the corner of the valve seat is materially formed non-rectangular and inclined, and propagation of axially rectangular vibrational energy of an ejecting current is reduced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a valve seat used in a plunger pump. More specifically, it relates to a valve seat for a plunger pump that prevents damage to the valve seat due to cavitation.

[0002]

2. Description of the Related Art In a plunger pump that generates high pressure,
Cavitation occurs. Cavitation damages the valve seat surface and reduces the function of the high-pressure pump. On the other hand, efforts have been made not to reduce the delivery flow rate even if the pressure is lowered by improving the leakage prevention means, but still, it is necessary to generate a high pressure of 1000 Kgf / square cm. However, even if the pressure is reduced in this way, it is still impossible to avoid damage to the seat surface.

FIG. 10 is a central sectional view showing a conventional valve seat 01 used in a plunger pump. The valve seat 01 has a flow channel 02 formed in the center. The flow channel 02 is orthogonal to the seat surface 03 on the cross section. In the valve seat having such a shape, the first seat surface 03 is damaged. Damage is traditionally described as caused by the high impacts that occur when cavitation bubbles collapse. It is explained that so-called water jet erosion occurs. Generally, water jet erosion damages the metal surface that is the first seat surface 03, but does not damage the second seat surface 04 formed of the elastic material that the applicant company valve seat has. This is because the detailed mechanism of damage is unknown, but the elastic body has a low hardness, or the natural frequency of the elastic body is the frequency generated by cavitation (the frequency of a cluster of a certain size of water). It is presumed that it is because it does not agree with).

FIG. 11 shows erosion on the valve seat side. The first sheet surface 03 inside the non-eroded second sheet surface 04 has eroded to a considerable extent. FIG. 12 shows erosion of the valve-side third seat surface 05. The eroded portion 06 of the third seat surface 05 is a surface facing the first seat surface of the valve seat 01. The degree of damage to the eroded portion 06 is remarkable. When such erosion begins, turbulence is increasingly generated, and the erosion progresses in a geometric progression.

In such a valve seat, the following phenomenon has been discovered in a high pressure improving machine in response to the recent demand for higher pressure. It has been successively found that the elastic body is not damaged at the sealing surface, but the elastic body is cut at the plane of the sheet surface 03 which is the sealing surface or a plane slightly approaching this plane on the upstream side.

Such a phenomenon cannot be explained without using a non-qualitative quantitative theory of water jet. Although theoretical analysis has not been completed at present, development of a sheet improved to a shape that does not cause such an erosion phenomenon is required.

[0007]

The present invention has been made based on such a technical background, and achieves the following objects.

An object of the present invention is to provide a valve seat for a plunger pump having a shape that does not cause an erosion phenomenon.

Another object of the present invention is to provide a valve seat for a plunger pump, in which a seat having an elastic surface and an inelastic surface is not damaged and the elastic body is not cut.

Another object of the present invention is to provide a valve seat for a plunger pump which achieves the above-mentioned object and substantially doubles the durability time.

Still another object of the present invention is to provide a valve seat for a plunger pump, in which the best material for achieving the above object is selected.

[0012]

The present invention employs the following means in order to solve the above problems.

The plunger pump valve seat according to the first aspect of the invention is elastic as the valve seat surface of the valve seat of the valve structure that is used by being arranged in the flow path of the high-pressure pulsating fluid generated by the plunger that reciprocates in the cylinder. A plunger pump valve seat in which an elastic surface of the surface of the body and an inelastic surface of the surface of the metal body are formed, and a flow path orthogonal to the valve seat surface is formed on the center side of the valve seat. The turbulent flow generation portion of the corner of the valve seat forming the above is deleted so that the corner of the valve seat is formed substantially non-perpendicular on the cross section.

The valve seat for the plunger pump according to the second aspect of the present invention is elastic as the valve seat surface of the valve seat of the valve structure that is used by being arranged in the flow path of the high pressure pulsating fluid generated by the plunger that reciprocates in the cylinder. An elastic surface on the surface of the body and an inelastic surface on the surface of the metal body are formed, and a flow path orthogonal to the valve seat surface is a plunger pump seat formed on the center side of the valve seat, A turbulent flow generation portion at the corner of the valve seat that is formed is deleted, and a wall surface of the wall that forms the flow path intersects the inelastic surface while being inclined with respect to the axial center line in a cross section.

A valve seat for a plunger pump according to a third aspect of the present invention is the valve seat according to the first or second aspect, wherein the elastic body is a material selected from fluororubber and polyurethane rubber, and has a hardness of JIS A 90 to 97 and a tensile strength. Is MPa
It is characterized by being 40 or more.

A valve seat for a plunger pump according to a fourth aspect of the present invention is the valve seat for the plunger pump according to the second aspect, wherein the wall surface is inclined by changing an inclination angle with respect to an axial center line and intersects with the inelastic surface. The inclination angle of is larger than the inclination angle of the downstream side.

A valve seat for a plunger pump according to a fifth aspect of the present invention is the valve seat according to the first or second aspect, wherein the elastic surface has a height of 0.1 mm to 0.3 m upstream of the inelastic surface.
It is characterized by high m.

A valve seat for a plunger pump according to a sixth aspect of the present invention is the one invention selected from the first, second, third, fourth and fifth aspects, wherein the process of deleting the turbulent flow generating portion is performed on both sides of the valve seat. It is characterized by what is done.

A valve seat for a plunger pump according to a seventh aspect of the present invention is characterized in that, in the sixth aspect, the valve seat is symmetrical with respect to a plane perpendicular to the axis.

The valve seat for the plunger pump according to the eighth aspect of the invention is elastic as the valve seat surface of the valve seat of the valve structure used by being arranged in the flow path of the high pressure pulsating fluid generated by the plunger reciprocating in the cylinder. An elastic surface on the surface of the body and an inelastic surface on the surface of the metal body are formed, and a flow path orthogonal to the valve seat surface is a plunger pump seat formed on the center side of the valve seat, A turbulent flow generation portion at the corner of the valve seat to be formed is deleted so that the wall surface of the wall forming the flow path is inclined with respect to the axis line in a cross section and intersects the inelastic surface, and is connected to the wall surface. A surface intersecting with the inelastic surface is formed on the elastic body.

In the present invention, since the nozzle, which is the discharge port of the valve seat, is enlarged with respect to the central flow passage, the non-elastic surface of the valve seat is not damaged. The reason is 100
It is presumed that this is because the vibration energy of the jet column created by the high-pressure fluid of 0 to 2000 Kgf / cm 2 is not transmitted to the inelastic surface of the valve seat.

Also, the valve seat is symmetrical with respect to the plane of symmetry on which the valve seat is fixed. This symmetry allows for reversal use and prevention of turbulence generation at the same time. Furthermore, since the wall surface forming the flow path crosses the inelastic surface by changing the inclination angle with respect to the axial center line on the cross section and the inclination angle on the upstream side is larger than the inclination angle on the downstream side. The inclination angle can be designed to be large on the discharge port side.

[0023]

BEST MODE FOR CARRYING OUT THE INVENTION Next, an embodiment of a valve seat for a plunger pump of the present invention will be described. FIG.
FIG. 1 is a front sectional view showing a first embodiment of a valve seat for a plunger pump of the present invention. As shown in FIG. 2, the pump 1 internally has a crankshaft 2 connected to an appropriate prime mover (not shown). A plunger 8 is connected to the crankshaft 2 via a crank 3, a pin 4, a slider 5, a connecting rod 6, a coupling 7, and the like.

The plunger 8 is fitted in a cylinder 10 formed in a cylinder block 9. Plunger 8
Are provided in the cylinder 10 so as to be reciprocally movable substantially coaxially. The plunger 8 is used as a piston for compressing a compressed fluid such as compressed air or compressed liquid, as will be described later. The suction port 11 is a suction port for sucking a fluid.

The suction valve mechanism 12 is a mechanism for sucking the fluid sucked from the suction port 11 and closing it at the time of compression. The discharge port 13 is a discharge port that discharges the compressed fluid. The discharge valve mechanism 14 is a mechanism for discharging a compressed fluid. The compression unit 15 between the suction port 11 and the discharge port 13 includes a compression chamber 16.

The leading portion of the plunger 8 plunges into the compression chamber 16 and moves back and forth. Intake valve mechanism 12 and discharge valve mechanism 1
4 has the same structure. The suction valve mechanism 12 and the discharge valve mechanism 14 each include the same valve seat 21. Details of the valve seat 21 are shown in FIG.

The valve seat 21 is, as shown in FIG.
It is formed in a substantially disk shape or a disk shape. The valve seat 21 is symmetrical about the axis of symmetry L and also symmetrical about the plane of symmetry S. The symmetry axis L and the symmetry plane S are orthogonal to each other. The valve seat 21 has a channel 22 formed in the center thereof. The flow path 22 is symmetrical with respect to the axis of symmetry L and the plane of symmetry S.

The direction of the flow path is set to one direction during use, but since the valve seat 21 is used upside down, the flow path direction is indicated by a bidirectional arrow 23 in the drawing. For convenience of explanation, the upper side in the figure is referred to as the upstream side, and the lower side in the figure as the downstream side. The valve seat 21 includes a metal body portion 24 and an elastic body portion 25.

The metal body portion 24 is induction hardened,
Its hardness is around HRC 60 degrees. The metal body portion 24 and the elastic body portion 25 are integrated by baking. The material of the elastic body portion 25 is selected from fluororubber and polyurethane rubber. Its hardness is JIS A 90
~ 97 are preferred.

Its tensile strength is 40 MPa or more.
For example, polyurethane rubber, the product name "Noxlan U652" manufactured by NOK is the best, and its hardness is JIS.
A hardness 96 degrees, its tensile strength is 43.2 (441) M
It is Pa (Kgf / square cm).

The metal body portion 24 is provided with an upstream recess 26U and a downstream recess 26D on the upstream side surface and the downstream side surface. The recess 26U and the recess 26D are each ring-shaped or annular. On the cross section, one of the recesses 26U is J
And the other has an inverted J shape. On the cross-section, one of the recesses 26D has a J shape and the other has an inverted J shape.

An elastic body having the same shape as the recess 26U is fitted in the recess 26U. This elastic body is the elastic body portion 25.
Is composed. The upstream side surface of the elastic body portion 25 is substantially flat. This plane is called the elastic sheet surface 27. The elastic sheet surface 27 is formed in a band shape and an annular shape.

The corners on both sides of the elastic sheet surface 27 are
It is slightly chamfered. The elastic body portion 25 is used as an exposed surface in addition to the elastic sheet surface 27 and the outer cylindrical surface 2
8 and has an axis-perpendicular surface 29. The axis-perpendicular surface 29 is the axis L
And is continuous with the outer cylindrical surface 28. The outer cylindrical surface 28 shares the symmetry axis L as a central axis.

The elastic sheet surface 27 is also provided symmetrically with respect to the symmetry plane S on the upstream side and the downstream side. Outer cylindrical surface 28
Is exposed, the inner cylindrical surface 31 is in close contact with the cylindrical surface forming the recess 26. Such two elastic body portions 25 are provided symmetrically with respect to the plane of symmetry S.

The flow path 22 formed by the metal body portion 24 at the center
Is composed of two types of wall surfaces. The wall is
It is a central cylindrical surface 32 and an inclined surface 33 that are bisected by the plane of symmetry S. The slopes 33 are provided at two locations on the upstream side and the downstream side. The two slopes 33 are symmetrical with respect to the plane of symmetry S.
The upstream slope 33 is formed continuously at the upstream end of the central cylindrical surface 32. The downstream slope 33 is formed continuously at the downstream end of the central cylindrical surface 32. This continuity does not necessarily have to be smooth. The upstream end of the upstream slope is connected to the non-elastic sheet surface 35. The non-elastic sheet surface 35 is an end surface on the upstream side of the metal body portion 24 and is a plane perpendicular to the axis.

There is a slight drop between the elastic sheet surface 27 and the non-elastic sheet surface 35. This drop is 0.2 mm
0.3 mm is preferred. The elastic sheet surface 27 on the upstream side is
It is located upstream from the upstream non-elastic sheet surface 35 and is located at a high position.

The non-elastic sheet surface 35 is a narrow but wide annular surface or ring-shaped surface. The existence of this width is for ensuring the strength of the metal body portion 24. The outer peripheral edges of the elastic body portion 25 on the upstream side and the downstream side are deleted. After this deletion, the O-ring fitting slope 3 described later
7 are formed.

FIG. 3 is an enlarged sectional view of the portion of the arrow circle CA in FIG. The slope 33 is formed as a compound slope. The downstream composite slope 33 is the upstream main slope 33.
a and the sub slope 33b on the downstream side. The main slope 33a and the downstream side slope 33b are formed continuously. The main slope 33a and the sub slope 33b are symmetrical with respect to the symmetry axis L and the symmetry plane S, respectively.

Although the connecting portion between the main slope 33a and the sub slope 33b on the downstream side is sharply formed, it is not necessarily required to be sharply formed and can be formed smoothly. Whether it is smooth or discontinuous is currently
Although it is undergoing an endurance test, it is presumed that the effect of suppressing turbulent flow generation is greater because it is better to drain water when discontinuous. The main slope 33a has an angle of about 15 degrees with the axis of symmetry L.
The sub slope 33b has an angle of about 45 degrees with the axis of symmetry L. In the experimental machine, the slope 33a is 15 with respect to the symmetry axis L.
The slope 33b was designed to be 45 degrees with respect to the axis of symmetry L. Other angles are currently under experimental planning,
It is estimated that the former is preferably 5 to 25 degrees and the latter is preferably 20 to 70 degrees. However, it is not limited to this range.

FIG. 4 shows the suction valve mechanism 12 shown in FIG.
Alternatively, there is shown an embodiment in which the valve seat 21 according to the present invention is assembled in the casing 41 constituting the discharge valve mechanism 14. The valve seat 21 shown in FIG. 4 is a valve seat on the side of the discharge valve mechanism 14. Casing 41
A washer 42 is fitted in close contact with the inner step surface of the. The spring seat 43 is integrally set up on the washer 42.

In order to make close contact with the downstream end face of the washer 42,
The valve seat 21 is fitted. Casing 41
Is sandwiched and fixed between the other casing 41a and the washer 42. Casing 41 and casing 41a
Are assembled so as to be removable in the axial direction.

The end face of the coil spring 44 is received by the spring seat 43. Coil spring 4
The valve 45 is biased toward the valve seat 21 by the other end surface of the valve 4. This urging direction is the axial direction of the axis of symmetry shown in FIG. The valve 45 is formed in a symmetrical shape with respect to the valve symmetry plane T fixed to itself.

The valve 45 is also symmetrical about the axis of symmetry L shared with the valve seat 21. The valve 45 is
The upstream end surface and the downstream end surface are formed on the sealing surface 46. Sealing surfaces on both sides are symmetry axis and valve symmetry surface T
Is symmetric to. Sealing surface 46 and elastic sheet surface 27
Are axially opposed and substantially parallel.

The elastic sheet surface 27, which is the end surface perpendicular to the axis of the elastic body portion 25 on the downstream side, is formed by the casing 41a when not in use.
It is in close contact with the step. The outer cylindrical surface 28 on the upstream side is in close contact with or close to the inner peripheral surface of the washer 42, that is, in close contact with it. The outer cylindrical surface 28 on the downstream side is in close contact with or close to the inner peripheral surface portion of the casing 41a, that is, in close contact with it. The upstream and downstream axis-perpendicular surfaces 29 are in close contact with the downstream side surface of the washer 42 and the step surface of the casing 41a.

Next, the operation / action of the first embodiment will be described. When the plunger of FIG. 1 advances to the right and the downstream side becomes high pressure in FIG. 4, the valve 45 moves the coil spring 44.
Moves up against the urging force of. On the contrary, when the plunger of FIG. 1 retracts to the left and the downstream side becomes low pressure in FIG. 4, the valve 45 is lowered by the biasing force of the coil spring 44. In this lowered state, the sealing surface 46 is
The elastic sheet surface 27 is pressed.

The valve 45 and the valve seat 21 which are pressed against each other
Thus, the flow path 22 is blocked. When the seal surface 46 of the valve 45 and the elastic seat surface 27 of the elastic body portion 25 are damaged to a certain extent, the casing 41a to the casing 4 are damaged.
1 is removed, the spring seat 43 is pulled out, the valve 45 and the valve seat 21 are further pulled out, and the valve 4
5 and the valve seat 21 are respectively inverted in the axial direction,
The valve 45 and the valve seat 21 are inserted in their original positions, the spring seats 43 are inserted, and the casing 41 is fitted back into the casing 41a to assemble. Such reversal use doubles the durability time.

Estimation of Physical Action In the open state shown in FIG. 4, the high-pressure fluid flows upward at a high speed by the arrow shown in FIG. The direction of the laminar flow approaching the central cylindrical surface 32 matches the direction of the axis of symmetry L. The fluid flowing in this direction maintains its direction even if it deviates from the surface of the central cylindrical surface 32. As shown in FIG. 5, the jet column J formed by the central cylindrical surface 32 is substantially the same as the jet column J even if the jet column J advances to the area surrounded by the main slope 33a.
Take the form extended in the direction of. Within the jet column J, static fluid dynamics are known to lose most of their physical meaning. The Pascal's principle is not applied, the pressure in the area indicated by the point P is extremely lower than that in the area indicated by the point A, and the energy density in the area near the point P is almost hollow. Therefore, in the area indicated by the point B, the momentum in the direction perpendicular to the axis is almost zero.

However, such an analysis is considered inadequate. The jet column J is known to be one vibrating solid. In this solid, water clusters vibrate vertically and horizontally to resonate. It is known that resonance natural frequencies appear in such clusters. That is, the vibration energy in the direction shown by the arrow C orthogonal to the central cylindrical surface 32 appears.

This vibration energy should diffuse in the region B in the direction perpendicular to the axis as shown in FIG. This diffusion flow newly forms a jet flow, and the non-elastic sheet surface 35
Between the seal surface 46 and the seal surface 46 generates natural vibration in a direction orthogonal to the arrow D. This vibration energy should damage the non-elastic sheet surface 35. However, the main slope 33a
Alternatively, the existence of the sub slope 33b does not cause this kind of damage according to the experiment.

Such a phenomenon is estimated as follows. The main slope 33a and the sub slope 33b are not parallel to the diametrically opposed parts. Therefore, the main slope 33
It is presumed that the a and the sub slope 33b do not cause resonance vibration in the jet column. Therefore, in FIG.
The flow indicated by cannot be a jet flow.

On the cross-section, the wall surface forming the flow path is inclined with the inclination angle changed with respect to the axial center line and intersects the inelastic surface,
Since the inclination angle on the upstream side is larger than the inclination angle on the downstream side, the inclination angle can be designed to be large on the discharge port side. With such a design, the vibrational energy of the jet flow can be diffused. The change in the tilt angle may be discontinuous or continuous.

For this reason, corrosion of the non-elastic sheet surface 35
It is estimated that erosion will not occur. Since the jet flow is not generated, the elastic body portion 25 is not cut. Similarly, cavitation destruction does not occur on the sealing surface 46 of the valve 45.

Since the portion to be used upside down is protected by a casing or the like, collision with foreign matter is prevented. There is no damage due to cavitation. When the damage progresses to a certain extent, it is used upside down. By suppressing damage and using it in reverse, the life of the high-pressure pump can be greatly extended.

FIG. 7 shows a second embodiment of the valve seat for a plunger pump according to the present invention. Embodiment 2
Has the same shape as that of the first embodiment except that the composite slope 33 of the first embodiment is replaced with the single slope 51. That is, the wall surface of the flow path 22 formed in the center of the metal body portion 24 is formed by the central cylindrical surface 32 and the sloped surface that are equally divided into two by the symmetry plane S, and the sloped surfaces 33 are provided at two locations on the upstream side and the downstream side. Two
The two slopes 33 are symmetrical with respect to the plane of symmetry S, the upstream slope 33 is continuously formed at the upstream end of the central cylindrical surface 32,
The downstream slope 33 is continuously formed at the downstream end of the central cylindrical surface 32, and the upstream end of the upstream slope is the non-elastic sheet surface 35.
The second embodiment is the same as the first embodiment in that the non-elastic sheet surface 35 is an upstream end surface of the metal body portion 24 and is a plane perpendicular to the axis.

However, the second embodiment differs from the first embodiment in that the wall surface of the flow path 22 formed at the center of the metal body portion 24 is formed by the central cylindrical surface 32 and the single inclined surface 51. The single inclined surface 51 intersects the inelastic sheet surface 35 in cross section. This intersection angle is non-perpendicular.

The reason for such improvement is as follows.
As shown in FIG. 8, the valve seat of the first embodiment used at a pressure of 300 kg / cm 2 or more causes the metal body portion 24 and the elastic body portion 25 to be separated by the fluid ejected in the direction perpendicular to the axis on the seat surface. Burrs B1 and B2 that are rolled and extend in the direction perpendicular to the axis are generated. The generation of such burrs has an adverse effect contrary to the damage preventing effect. It has been confirmed by experiments that the sub-slopes 33b are rather damaged and promoted when the pressure of the fluid used is increased to some extent.

In the valve seat of the second embodiment in which the sub slope 33b is not formed, such a burr does not occur even when used at a pressure of 300 kg / square cm or more.

FIG. 9 shows a third embodiment of the valve seat according to the present invention. The point that the slope is a single slope 51 is the same as in the second embodiment. The wall surface on the flow path 22 side of the elastic body portion 25 of the valve seat of the third embodiment is formed as an elastic slope 52. Elastic slope 52 and single slope 5
1 and 1 form the same slope, that is, the same conical surface. The non-elastic sheet surface 35 of the first and second embodiments (the surface on the flow path side) is not formed in the third embodiment.

Also in the valve seat of the third embodiment, burrs do not occur even when used under high pressure.

[0060]

According to the valve seat for the plunger pump of the present invention, the life is remarkably extended due to the damage preventing function and the reverse use.

[Brief description of drawings]

FIG. 1 is a front sectional view showing a first embodiment of a valve seat for a plunger pump of the present invention.

FIG. 2 is an enlarged sectional view of the valve seat in FIG.

FIG. 3 is an enlarged cross-sectional view of a portion of FIG.

FIG. 4 is an enlarged cross-sectional view of a main part of FIG.

FIG. 5 is a conceptual diagram showing the estimation principle of the valve seat for the plunger pump of the present invention.

FIG. 6 is a conceptual diagram showing the estimation principle of the valve seat for the plunger pump of the present invention.

FIG. 7 is a front sectional view showing a second embodiment of the valve seat for the plunger pump of the present invention.

FIG. 8 is a front sectional view showing occurrence of burrs when the valve seat of Embodiment 1 is used.

FIG. 9 is a front sectional view showing a third embodiment of the valve seat for the plunger pump of the present invention.

FIG. 10 is a cross-sectional view showing the prior art.

11 is a perspective view showing erosion damage to the prior art valve seat of FIG.

12 is a perspective view showing erosion damage to the prior art valve of FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Pump 21 ... Valve seat 22 ... Flow path 22 24 ... Metal body part 25 ... Elastic body part 27 ... Elastic sheet surface 28 ... Outer cylindrical surface 29 ... Axial right angle surface 32 ... Central cylindrical surface 33, 51 ... Slope 33a ... Main Slope 33b ... Sub slope 35 ... Inelastic sheet surface

Claims (8)

[Claims] 1. An elastic surface of an elastic body and a metal body as a valve seat surface of a valve seat of a valve structure arranged and used in a flow path of a high-pressure pulsating fluid generated by a reciprocating plunger in a cylinder. Is a plunger pump valve seat in which a non-elastic surface of the surface of the valve seat is formed, and a flow path orthogonal to the valve seat surface is formed on the center side of the valve seat. A valve seat for a plunger pump, in which a turbulent flow generation portion is deleted and corners of the valve seat are formed substantially non-perpendicular on a cross section. 2. An elastic surface of an elastic body and a metal body as a valve seat surface of a valve seat of a valve structure arranged and used in a flow path of high-pressure pulsating fluid generated by a plunger reciprocating in a cylinder. Is a plunger pump seat in which a non-elastic surface is formed and a flow path orthogonal to the valve seat surface is formed on the center side of the valve seat, and the angular disturbance of the valve seat forming the flow path is disturbed. A valve seat for a plunger pump, wherein a wall surface of a wall forming a flow path by removing a flow generating portion intersects with the inelastic surface while being inclined with respect to an axial center line in a cross section. 3. The elastic body according to claim 1, wherein the elastic body is a material selected from fluororubber and polyurethane rubber, has a hardness of JIS A 90 to 97, and a tensile strength of 40 MPa or more. Valve seat for plunger pump. 4. The wall surface according to claim 2, wherein the wall surface inclines by changing an inclination angle with respect to an axial center line and intersects the inelastic surface, and the inclination angle on the upstream side is the inclination angle on the downstream side. Valve seat for plunger pumps that is larger than 5. The valve seat for a plunger pump according to claim 1, wherein the elastic surface has a height of 0.1 mm to 0.3 mm higher on the upstream side than the inelastic surface. 6. One selected from claims 12, 3, 4, and 5.
The valve seat for a plunger pump according to claim 1, wherein the process of deleting the turbulent flow generation portion is performed on both surfaces of the valve seat. 7. A valve seat for a plunger pump according to claim 6, which is symmetrical with respect to a plane perpendicular to the axis. 8. An elastic surface of an elastic body and a metal body as a valve seat surface of a valve seat of a valve structure arranged and used in a flow path of a high-pressure pulsating fluid generated by a plunger reciprocating in a cylinder. Is a plunger pump seat in which a non-elastic surface is formed and a flow path orthogonal to the valve seat surface is formed on the center side of the valve seat, and the angular disturbance of the valve seat forming the flow path is disturbed. A surface in which the flow generation portion is deleted and the wall surface of the wall that forms the flow path intersects the inelastic surface while being inclined with respect to the axial center line in the cross section, and connecting to the wall surface and intersecting the inelastic surface. A valve seat for a plunger pump, in which the elastic body is formed.