JP3261091B2 - Eccentric butterfly valve - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an eccentric butterfly valve for opening and closing or controlling the flow of a high-temperature fluid in piping, and more particularly to an eccentric butterfly valve which can be used stably for a long period of time.

[0002]

2. Description of the Related Art A conventional example of a conventional triple eccentric butterfly valve in which one of the contact surfaces of a valve element and a seat ring is inclined with respect to the other in a cross section perpendicular to a valve stem is disclosed in JP-B-47-16895. And Japanese Patent Publication No. 3-10828 and Japanese Utility Model Laid-Open No. 57-59258.

[0003] This requires a member such as a mounting plate for fixing a valve seat such as an elastomer on the outer peripheral edge of the valve body. Generally, the shape of the valve body, especially its thickness becomes large, so that pressure loss when the valve body is fully opened is reduced. Similarly, there is a risk that the above members and the like vibrate and fall off due to high flow velocity in the valve body. In addition, since the upstream end of the valve body when fully opened is worn out by impurities, foreign matters, hard sand, or the like contained in the fluid, and when fully closed, it is difficult for the valve body to reliably press against the main body side valve seat. Was causing the leak.

[0004]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems of the conventional eccentric butterfly valve, and fixes the seat ring on the main body side instead of the outer peripheral edge of the valve body. In particular, the thickness can be made thinner within a range allowable in strength, and the valve body is formed of a material corresponding to the foreign matter contained in the fluid, or
An object of the present invention is to provide an eccentric butterfly valve capable of performing a wear resistance treatment on an outer peripheral edge of a valve body.

[0005]

In order to solve the above-mentioned problems, the present invention employs a valve body having a substantially cylindrical fluid passage formed therein, and a rotary member provided in the valve body through a valve stem. A disc-shaped valve body made of a rigid material that is freely rotatably supported, and a seat surface formed on the outer peripheral surface of the valve body and a seat ring attached to the valve body are moved from the center of the valve body to the center of the valve stem. The primary eccentricity to be separated, the secondary eccentricity to be separated from the center line of the valve body, and the conical apex constituting the sealing surface of the valve body and the valve body are located on the opposite side of the valve stem while the center eccentricity is set to It is a tertiary eccentric tilting and inserting the inner peripheral surface of the seat ring which is formed into an elliptical shape to the valve body with the outer peripheral surface in a circular, outer peripheral surface of the seat ring mounting bolts to secure the seat ring in the valve body At the same pitch on the concentric circle with the outer peripheral surface of the seat ring Eccentric type butterfly valve odor that was set
And the seat press that faces the valve body with the seat ring in between.
The seat retainer and the seat ring are attached to the valve body.
And secure the inner surface of the sheet retainer to the seat
A similar ellipse larger than the inner circumference of the
Provide a step on at least one fastening surface of the seat ring
A step that increases the thickness of the outer peripheral side and engages the step
Of the valve body or the seat ring in the seat retainer.
The inner peripheral surface of the valve body matches the elliptical shape of the outer periphery of the valve body.
It is formed in a similar large elliptical shape and the gap between the valve body and the valve
Constant over the circumference, valve body, seat ring and seat
It is characterized in that a matching mark is provided on the presser .

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below in detail with reference to the drawings. In FIG. 1, a substantially cylindrical fluid passage (2) is provided through a valve body (1).
A valve body (3) is rotatably supported in the valve body (1) via a valve rod (4). The valve body (3) has a disk shape made of a rigid material having an elliptical outer peripheral surface, and a valve stem (4) is attached to a valve stem pin (6).
It is fixed with. Then, one end of the valve stem (4) extends out of the valve body (1) and is connected to an actuator (not shown).
The valve body (3) is rotated via (4).

Further, a seat ring (5) pressed against the outer peripheral surface of the valve body (3) is fixed to the inner peripheral surface of the valve body (1). The inner peripheral surface of the seat ring (5) is formed in an elliptical shape following the outer peripheral surface of the valve body (3), and is fixed to the valve body (1) by the seat retainer (7) while the valve body (3) is fixed. A primary eccentricity that separates a seat surface formed on the outer peripheral surface and a seat ring (5) attached to the valve body (1) from the center of the valve body (3) and the center of the valve rod (4);
Of the valve body (1) while the secondary eccentricity away from the center line of the valve body and the conical apex forming the sealing surface of the valve body (1) and the valve body (3) are located on the opposite side of the valve stem (4). An eccentric butterfly valve having a third eccentricity inclined with respect to the center line is configured.

[0008] The seat ring (5) is a metal sheet material obtained by laminating a thin metal plate and graphite (graphite).
It is fixed by being sandwiched between the valve body (1) and the seat presser (7). Also, by providing a step on each of the contact surfaces of the valve body (1) and the seat retainer (7) with the seat ring (5), and engaging the step of the seat ring (5) with this step, The seat ring (5) is prevented from protruding in the inner diameter direction. A plurality of bolt holes (9) provided in the seat ring (5) and the seat retainer (7) are respectively passed through mounting bolts (8), which are fixed together with the valve body (1).
(8) are arranged at an equal pitch on the concentric circle with the outer peripheral surface of the seat ring (5) at the middle between the outer peripheral surface and the inner peripheral surface of the seat ring (5).

As shown in FIGS. 2 and 3, the inner diameter of the seat retainer (7) is made to be a large ellipse similar to the inner diameter of the seat ring (5), so that the seat retainer (7) and the valve element ( 3)
In addition to avoiding contact with the valve body and taking into account the inner diameter of the valve body with respect to the outer diameter of the seat ring, the self-aligning function of the seat ring (5) by contact with the valve body (3) is ensured. .

The inner peripheral surface of the seat ring (5) and the valve body
The outer peripheral surface of (3) has an elliptical shape. Also, valve body
The outer peripheral edge of (3) and the inner peripheral edge of the seat ring (5) are formed to have substantially the same diameter with a slightly larger valve body and a slightly smaller seat ring. And, as shown in FIG. 6, the valve body (3) is a valve stem.
(5) rotates counterclockwise around the axis (i),
The axis (i) of the valve stem (5) is located on the opposite side of the vertex (a) of the conical surface formed by the outer peripheral surface of the valve body (3), and the center line (e) of the valve body (3).
From the center line (h) of the valve body and the valve body by the secondary eccentricity (g). The apex (a) is located on the horizontal line (b) of the horizontal valve seat (A), the apex angle (j) is usually preferably about 20 degrees, and the inclined valve seat (B) is located on the other inclined line (d). ) Is provided. And the apex angle
The half angle of (j) is the center line (c) of the cone, and the valve body (3), the valve seat and the like are formed symmetrically with respect to the center line (c).

On the other hand, the outer peripheral surface of the seat ring (5) and the valve body
The inner peripheral surface of (1) has a perfect circular shape, and the sheet retainer
The seat ring (5) is fixedly fixed to the valve body (1) via (7). Then, as shown in FIG.
A registration mark (10) for positioning is provided on the outer peripheral surface of the seat ring, and a registration mark corresponding to the registration mark (10) is provided on the seat ring (5) and the valve body (1). Therefore,
Outer periphery of seat retainer (7), seat ring (5) and valve body
The inner circumference of (1) is both circular, and the mounting bolt (8)
Seat ring (5) and seat presser depending on tightening condition
There is a concern that the fixing position of (7) is deviated in the circumferential direction.
Seat ring (5) by matching the matching mark (10)
In addition, the fixing position of the sheet presser (7) is prevented from being biased in the circumferential direction. On the other hand, the valve element (3) fixed to the valve stem (4)
The elliptical shape of the outer peripheral edge of the valve body is determined in the axial direction of the valve stem, and the reliable fixing to the conical valve seat leads to an improvement in the effect of preventing leakage.

An inner peripheral surface of the seat retainer (7) for fixing the seat ring (5) has a structure similar to that shown in FIG.
It is formed in a similar elliptical shape larger than the inner peripheral surface of (5), and the projecting length of the valve body (3) in the inner diameter direction of the seat ring (5) on the previous page is constant over the entire circumference. By doing so, the amount of pressurized deformation by the valve body (3) when fully closed is made constant over the entire circumference to obtain a stable sealing property.

In FIG. 6, the input angle (k) corresponds to the valve element (3).
Indicates the angle at the time of sitting from opening to closing, and is desirably set to about 15 degrees from the viewpoint of sealing performance and ease of valve opening / closing (separation and seating). That is, when the input angle (k) is large, the opening and closing of the valve is easy, but the sealing performance is reduced. Conversely, when the input angle (k) is small, the opening and closing of the valve is improved despite the increased sealing performance. Becomes difficult.

In FIG. 7, the valve stem (4) is disposed horizontally, the fluid flow direction is on the left side (flat side of the valve body (3)), the tilt valve seat is downward, and the horizontal valve seat is By rotating the valve body (3) in the counterclockwise direction as the upper side, when controlling seawater or the like in which foreign matter or the like is mixed in the fluid, the foreign matter is removed from the valve body (3) as shown by a broken line in FIG. It can be seen that the opening and closing properties of the valve element (3) are ensured because it is deposited at a position opposite to the rotation direction.

In FIG. 1, when the fluid flow is on the flat side of the valve body (3), the force due to the fluid flow acting on the valve body (3) theoretically acts in the direction of the open side, so that the sealing property is reduced. Although reduced, ease of opening and closing and rotational torque are improved.
On the other hand, when the flow is on the valve stem side, the sealing property is increased due to the closing force and the self-acting force acts, but the opening / closing property and the rotation torque are increased. However, the stem rotation torque increases by about 40%.

[0016]

According to the eccentric butterfly valve according to the present invention, the seat ring conventionally attached to the valve body is fixed to the valve body side.
It is possible to reduce the pressure loss by reducing the thickness within a range where the strength is allowed, and it is not necessary to attach an accessory that causes vibration or dropping due to the fluid flow to the valve body, and is included in the fluid. constitutes the valve body with a material corresponding to the foreign substance, or when it is possible to stably use over a long subjected to abrasion resistance treatment of the valve outside periphery co
In addition, it is possible to more reliably prevent the seat ring from protruding in the inner diameter direction due to the fluid flow, and the amount of protrusion of the seat ring from the seat presser can be kept constant over the entire circumference. Therefore, the sealing property is improved. Further, when the matching marks are provided on the valve body, the seat ring, and the seat retainer, it is possible to easily avoid the bias of the fixing position of the seat ring or the like by assembling them in accordance with each other.

[Brief description of the drawings]

FIG. 1 is a sectional view of an eccentric butterfly valve according to the present invention.

FIG. 2 is a partially enlarged sectional view showing a contact state between a valve body and a seat ring when the valve is closed.

FIG. 3 is a partially enlarged sectional view showing a state of a valve body and a seat ring when the valve is opened.

FIG. 4 is a front view of the sheet presser.

FIG. 5 is a side view of FIG. 4;

FIG. 6 is an explanatory diagram showing a relationship between a valve rod and a valve seat in a valve body.

FIG. 7 is an explanatory diagram showing a relationship between a valve element, a seat ring, and a fluid flow.

[Explanation of symbols]

 (1) Valve body (2) Fluid passage (3) Valve (4) Valve stem (5) Seat ring (6) Valve stem pin (7) Seat retainer (8) Mounting bolt (9) Bolt hole (10) mark

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-64-87977 (JP, A) JP-A-8-75013 (JP, A) JP-A-1-91168 (JP, U) JP-A-61-168 49165 (JP, U) Fully open sho 56-76751 (JP, U) Really open sho 58-138865 (JP, U) Fully open sho 57-59258 (JP, U) Fully open sho 56-34163 (JP, U) Patent No. 269556 (JP, B2) JP 6-86912 (JP, B2) JP 3-10828 (JP, B2) JP 47-6995 (JP, B1) JP 1-41866 (JP, B2) ) Jigyo 51-23383 (JP, Y1) Jigyo Hei 3-29643 (JP, Y2) (58) Fields surveyed (Int. Cl. ⁷ , DB name) F16K 1/16-1/226 F16K 27 / 02

Claims (1)

(57) [Claims] A valve body penetrating a substantially cylindrical fluid passage; a disc-shaped valve body made of a rigid material rotatably supported in the valve body via a valve rod; A primary eccentricity that separates a seat surface formed on an outer peripheral surface of a valve body and a seat ring attached to the valve body from the center of the valve body and the center of a valve rod; a secondary eccentricity that is away from a center line of the valve body; And the third eccentricity to incline with respect to the center line of the valve body while positioning the conical apex constituting the sealing surface of the valve body on the opposite side of the valve stem ,
A seat ring having an outer peripheral surface formed into a circular shape and an inner peripheral surface formed into an elliptical shape is inserted into a valve body, and mounting bolts for fixing the seat ring to the valve body are provided between the outer peripheral surface and the inner peripheral surface of the seat ring. In an eccentric butterfly valve arranged at a constant pitch on the concentric circle with the outer peripheral surface of the seat ring ,
A seat press is provided opposite the valve body with the
The plate retainer and seat ring are fastened together to the valve body with mounting bolts.
Fix the inner surface of the seat retainer to the inner surface of the seat ring.
Into a larger similar ellipse and seat ring
Provide a step on at least one of the tightening surfaces of
And the step engaging with the step is formed by the valve body or
Is formed on the contact surface with the seat ring in the sheet holder
The inner peripheral surface of the valve body has a large
It is formed in an elliptical shape, and the gap between the valve body and the valve
Make the valve body, seat ring and seat retainer
An eccentric butterfly valve characterized by the provision of a valve.