JP3213901B2 - Abnormality notification device in valve device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a valve device in which a valve stem is moved in the axial direction or rotated around the axis to open and close a valve body. The present invention relates to a notification device that enables constant and quantitative information on changes in properties of a certain gland packing, other packings, a valve body, and the like.

[0002]

2. Description of the Related Art For example, a linear drive type actuator having a piston, a diaphragm or a bellows is operated by using pressurized air or other pressurized fluid, and if necessary, a return spring is added to form a valve stem. In a valve device that opens and closes a valve element by reciprocating in an axial direction, or a valve device that opens and closes a valve element by rotating a valve rod around an axis by a rotary actuator. However, the following abnormal or inappropriate state may occur.

[0003] (a) The gland packing provided between the valve stem and the valve box is weakened due to deterioration with time or the influence of temperature or pressure, and the sliding friction force with the valve stem and, consequently, the seal. Is reduced.

[0004] (b) If the actuator has a piston inserted into a cylinder, (a) the piston ring fitted to the outer periphery of the piston may change over time.
The same situation occurs.

(C) Due to the properties of the controlled fluid, the temperature, the pressure, the presence or absence of foreign substances, and the wear of the valve body, etc.,
When the valve body contacts or separates from the valve seat, the resistance value received by the valve stem changes.

(D) When the actuator is provided with a return spring, the operation may be inappropriate even if the spring is weakened.

When the above-mentioned situation occurs, the sliding frictional force of the valve stem becomes excessively large or small, which causes an operation failure such as hunting and the like, which has a considerable adverse effect on the operation of the valve device and, consequently, the operation of the system including the valve device. It will be.

If hunting occurs in the valve stem during the operation of the valve device, the operation of the valve stem becomes defective and uncertain, and the feedback to the actuator or the like is not performed properly, and the self-control of the valve is impaired. Becomes Also,
If the sliding frictional force of the valve stem falls below a certain limit, the seal will be defective and the valve stem will not operate quickly and powerfully.

In order to suppress the occurrence of such a situation as much as possible, it is always necessary to determine whether or not the operating resistance of the valve stem is within a certain range regardless of the elapse of the use time or the change in temperature. Need to be monitored and managed.

[0010]

In order to solve the above problem, a strain gauge may be directly attached to the valve stem.
It is difficult to securely attach the strain gauge to withstand long-term operation, and during operation, a part or the whole of the strain gauge may peel off or move.

[0011]

SUMMARY OF THE INVENTION The present invention is to solve the above-mentioned problems of the prior art by providing a strain gauge integrally in a valve stem by simple means. Means are as follows.

(1) In a valve device in which a valve body is opened and closed by moving a valve stem in the axial direction, an axially-oriented mounting hole is provided at an appropriate position of the valve stem, and a side surface of the mounting hole has a distortion. The gauge is attached with its detection direction oriented in the axial direction.

(2) In the above item (1), an axial mounting on the valve stem at an appropriate position between the valve stem driving portion and a gland packing for holding the valve stem provided on the valve box or the bonnet attached thereto. A hole is provided, and a strain gauge is attached to a side surface of the mounting hole with its detection direction directed in the axial direction.

(3) In the above item (1) or (2), the valve stem driving section is a diaphragm actuated by a pressurized fluid, and the upper end of the valve stem is fixed to the diaphragm and the upper end of the valve stem. A strain gauge is attached to the side surface of the mounting hole so that its detection direction is oriented in the axial direction.

(4) In the above item (1) or (2), the valve stem driving section is a piston provided in the cylinder and operated by a pressurized fluid, and the upper end of the valve stem is connected to the bottom of the cylinder. The upper end of the valve stem is fixed to the piston through a seal ring in a through hole provided in the wall, and the side surface of the axial mounting hole provided in the valve stem above the seal ring is distorted. The gauge is attached with its detection direction oriented in the axial direction.

(5) In the above item (4), a strain gauge is attached to a side surface of an axial mounting hole provided in the valve stem below the seal ring, with a detection direction directed in the axial direction.

(6) In a valve device in which a valve body is opened and closed by rotating a valve stem around an axis, a mounting hole is provided at an appropriate position of the valve stem, and a strain gauge is provided on a side surface of the mounting hole. The detection direction is attached in the circumferential direction.

(7) In the above item (6), a strain gauge whose detection direction is the axial direction is attached to the side surface of the mounting hole.

[0019]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a vertical sectional front view showing an example of a diaphragm-operated flow path on-off valve to which an embodiment of the invention described in claims 1 to 3 is applied.

The valve box (1) has an inflow cylinder connected to the flow path (2).
An inflow cylinder (3) and an outflow cylinder (4) by a substantially horizontal partition wall (6) having (3) and an outflow cylinder (4) on the left and right and having a vertical valve hole (5) in the center. A lower inflow chamber (7) and an upper outflow chamber (8) are formed.

The upper edge of the valve hole (5) is formed in a downward conical surface (5a), and an annular valve seat (9) is fixed thereto.

A vertical support hole (12) at the center of a bonnet (11) fixed to the upper surface of the valve box (1) with an appropriate number of bolts (10).
Inside, through the gland packing (13), the long valve stem
(14) is inserted so that it can slide up and down. The bonnet (11) may be formed integrally with the valve box (1).

The lower end of the valve stem (14) moves away from the valve seat (9) as it moves up and down with it,
A valve body (15) for closing the valve hole (5) in contact with (9) is provided.

The gland packing (13) has a support hole (12).
The lower end of the gland packing (13) is received by the shoulder at the lower end of the large diameter hole (12a). The upper end of the gland packing (13) is a support piece (17) secured to the upper surface of the bonnet (11) with a bolt (16).
Is held by

The upper portion of the valve stem (14) rises in a cylindrical yoke (19) attached to the upper surface of the bonnet (11) with bolts (18), and the upper surface of the yoke (19) has a cover ( It projects into a slightly flat circular housing (22) integrally attached via the common bolt (21) via the common bolt (21).

The circular housing (22) is formed by tightening a bolt (23) around the upper and lower half housings (22a) and (22b).
The periphery of the diaphragm (24) is sandwiched between the periphery of b).

At the center of the diaphragm (24), a pressure receiving disc
(25) is fixed, and the male screw portion (14a) at the upper end of the valve stem (14) is tight in the capped female screw hole (25a) drilled from the lower surface at the center of the pressure receiving disk (25). It is screwed.

An exhaust hole is provided at the center of the upper surface of the upper half housing (22a).
(26) is located on one side of the lower surface of the lower half housing (22b).
7) is provided.

At an appropriate position in the yoke (19), a spring bearing (28) that can slide up and down is inserted into the valve stem (14),
The lower surface of (28) is held by an adjusting cylinder (29) screwed into a male thread (14b) provided on the valve stem (14).

Between the cover plate (20) and the spring receiver (28), a compression coil spring (30) is inserted into the valve stem (14), whereby the valve stem (14) is attached downward. It is being rushed.

A mounting hole (14c) is formed in the valve stem (14) so as to extend in the axial direction from the upper surface. Below the lower half housing (22b), an inner surface of the mounting hole (14c) is provided. A strain gauge (31) is attached with its detection direction oriented in the axial direction. The lead wire (31a) of the strain gauge (31) is led out through a lead hole (14d) provided on the side of the mounting hole (14c). Mounting hole
(14c) may be in the form of a slit.

According to the above configuration, when the axial distortion occurs in the valve stem (14), the electric resistance value of the strain gauge (31) changes accordingly, and the value is appropriately amplified and output. The change in the opening and closing resistance of the valve element (14), the sliding resistance of the gland packing (13), and the elasticity of the diaphragm (24) can be immediately and quantitatively known, and the change value is If a certain limit is exceeded, a warning can be issued if necessary.

Therefore, without disassembling the valve box (1), the yoke (19), etc., an abnormality has occurred in the valve body (15) or the valve seat (9), or the gland packing (13) has deteriorated with time. In this way, it is possible to know whether or not the state requires replacement, and timely and appropriate maintenance can be performed.

FIG. 2 is a partial vertical perspective view of an essential part showing an example of a piston-operated flow passage opening / closing valve to which the embodiments of the invention described in claims 4 and 5 are applied.

The upper end of a valve stem (41) similar to that shown in FIG. 1 is fixed to the lower surface of a double-acting piston (43) in a vertical cylinder (42), and therefore, as in FIG. No biasing compression coil spring is provided. The valve body and others are basically the same as those in FIG. Therefore, only the upper end of the valve stem (41) will be described with reference to FIG.

The vertical cylinder (42) has a closed cylindrical shape,
At the upper and lower ends of the side walls, intake and exhaust ports (44) and (45) are provided, respectively.

The piston (43) has a fitting groove (43a) on the outer peripheral surface, and a piston ring (46) is fitted therein.

The upper portion of the valve stem (41) penetrates through a through hole (42b) formed in the center of the bottom wall (42a) of the vertical cylinder (42) and protrudes into the vertical cylinder (42). The upper end is appropriately fixed to the lower surface of the piston (43) as described above.

A circumferential groove (42) is formed on the side surface of the through hole (42b).
c) is provided, into which a seal ring (47) appropriately abutting on the side surface of the valve stem (41) is fitted.

A linear mounting hole (41a) (which may be a slit) is formed downward from the upper end of the valve stem (41), and the mounting hole (41) is formed above and below the seal ring (47).
On the inner surface of a), strain gauges (48) and (49) are attached with the detection direction thereof being the axial direction. Each strain gauge (48) (49)
The lead wires (48a) and (49a) are led out through an extraction hole (41b) provided on the side surface of the mounting hole (41a).

The degree of deterioration and wear of the piston ring (46) and the seal ring (47) can be quantitatively determined by the change in the strain value indicated by the upper strain gauge (48).

Further, from the change in the strain value indicated by the lower strain gauge (49), the degree of deterioration and wear of the gland packing (not shown) and the change in the resistance value of the valve body can be known.

FIG. 3 is a partial longitudinal perspective view showing an example in which the present invention is applied to a ball valve according to the sixth embodiment.

The lower end is locked or fastened to a ball-shaped valve element (not shown), and the upper end of a valve stem (51) pivotally supported by a valve box (not shown) via a gland packing (50). Is connected to an appropriate rotary actuator (52), whereby it is rotated forward and backward to open and close the flow path.

An axial mounting hole (53) is formed in the valve stem (51) from the upper end face, and a strain gauge (54) is provided on the side face thereof.
It is attached with the detection direction facing the circumferential direction.

The lead wire (54a) of the strain gauge (54) is led out through a lead hole (53a) provided on the side of the mounting hole (53).

The mounting hole (53) may be provided in the centripetal direction from the side surface of the valve stem (51), and after attaching the strain gauge (54), the mounting hole (53) may be closed with a blind lid. .

In the mounting hole (53), a circumferential strain gauge (5
In addition to 4), an axial strain gauge (not shown) may be attached.

By the change of the strain value indicated by the strain gauge (49), it is possible to know the deterioration of the function due to the deterioration or wear of the gland packing (50) and the valve seat which contacts the ball-shaped valve element (not shown).

[0050]

(A) The invention according to the first aspect is characterized in that the change in the strain value in the axial direction of the valve stem indicated by the strain gauge causes the deterioration of the function due to the deterioration of the valve stem supporting portion and the valve element portion to be constantly and constantly performed. It is possible to know quantitatively and take measures in a timely manner. Also, since the strain gauge is mounted inside the valve stem, it is completely isolated from external substances and the environment, etc., and does not move or peel off.

(B) Invention of Claim 2 Deterioration and wear of the gland packing can be constantly and quantitatively known.

(C) Invention of Claim 3 Changes in the properties of the diaphragm can be constantly and quantitatively known.

(D) Invention of Claim 4 Deterioration or weakening of the seal ring of the piston pivot portion in the cylinder and the piston ring on the outer peripheral surface of the piston can be constantly and quantitatively known.

(E) The deterioration of the functions of the valve stem supporting member and the valve element below the seal ring of the piston pivot portion of the cylinder can be always and quantitatively known.

(F) The deterioration of the function of the gland packing and the valve body in the circumferential direction of the valve stem can be always and quantitatively known.

(G) Invention of Claim 7 Changes in the properties of the gland packing and the valve element in the circumferential direction and axial direction of the valve stem can be constantly and quantitatively known.

[Brief description of the drawings]

FIG. 1 is a vertical sectional front view showing an example of a diaphragm-operated flow passage opening / closing valve to which the invention described in claims 1 to 3 is applied.

FIG. 2 is a partially longitudinal perspective view showing a main part of a piston-operated flow path on-off valve to which the inventions according to claims 4 and 5 are applied.

FIG. 3 is a partially longitudinal perspective view showing a main part of a ball valve to which the invention described in claim 6 is applied.

[Explanation of symbols]

 (1) Valve box (2) Flow path (3) Inflow cylinder (4) Outflow cylinder (5) Valve hole (5a) Conical surface (6) Partition wall (7) Inflow chamber (8) Outflow chamber (9) Valve seat (10) Bolt (11) Bonnet (12) Support hole (12a) Large diameter hole (13) Gland packing (14) Valve stem (14a) (14b) Male thread (14c) Mounting hole (14d) Lead-out hole (15 ) Valve (16) Bolt (17) Receptacle (18) Bolt (19) Yoke (20) Cover plate (21) Bolt (22) Circular housing (22a) (22b) Half housing (23) Bolt (24 ) Diaphragm (25) Pressure receiving disk (25a) Female screw hole (26) Exhaust hole (27) Air guide hole (28) Spring receiver (29) Adjustable cylinder (30) Compression coil spring (31) Strain gauge (31a) Lead wire (41) Valve stem (41a) Mounting hole (41b) Removal hole (42) Vertical cylinder (42a) Bottom wall (42b) Through hole (42c) Concave groove (43) Piston (43a) Fitting groove (44) (45) Intake and exhaust port (46) Piston ring (47) Seal ring (48) (49) Strain gauge (48a) (49a) Lead wire (50) Gland packing (51) Valve stem (52) Rotary actuator

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-8-261355 (JP, A) JP-A-5-52276 (JP, A) JP-A-1-187432 (JP, A) 46706 (JP, B2) (58) Fields investigated (Int. Cl. ⁷ , DB name) F16K 37/00 F16K 51/00

Claims (7)

(57) [Claims] In a valve device in which a valve body is opened and closed by moving a valve stem in an axial direction, an axially oriented mounting hole is provided at an appropriate position of the valve stem, and a strain gauge is provided on a side surface of the mounting hole. An abnormality notification device in a valve device characterized in that the detection direction is attached in the direction of the axis. 2. An axial mounting hole is provided in a valve stem at an appropriate position between a valve stem driving portion and a gland packing for holding a stem provided on a valve box or a bonnet attached thereto. 2. A strain gauge is attached to a side surface with its detection direction oriented in the axial direction.
An abnormality notification device in the valve device described in the above. 3. The valve stem driving section is a diaphragm actuated by pressurized fluid. The diaphragm has an attachment hole fixed to an upper end of the valve stem and an attachment hole extending in an axial direction from the upper end of the valve stem. The abnormality notification device for a valve device according to claim 1 or 2, wherein a strain gauge is attached to a side surface of the hole so that a detection direction of the strain gauge is oriented in an axial direction. 4. The valve stem drive unit is a piston provided in the cylinder and operated by a pressurized fluid. The upper end of the valve stem is connected to a through hole provided in the bottom wall of the cylinder through a seal ring. With the upper end of the valve stem fixed to the piston, and a strain gauge on the side of the axial mounting hole provided in the valve stem above the seal ring, with the detection direction directed in the axial direction. The abnormality notification device in the valve device according to claim 1, wherein the abnormality notification device is attached. 5. The strain gauge according to claim 4, wherein a strain gauge is attached to a side surface of an axial mounting hole provided in the valve stem below the seal ring so that a detection direction thereof is directed in the axial direction. Abnormality notification device in valve device. 6. A valve device in which a valve body is opened and closed by rotating a valve stem around an axis, wherein a mounting hole is provided at an appropriate position of the valve stem, and a strain gauge is provided on a side surface of the mounting hole. An abnormality notification device for a valve device, wherein the detection direction is attached in a circumferential direction. 7. The abnormality notification device for a valve device according to claim 6, wherein a strain gauge whose detection direction is an axial direction is attached to a side surface of the mounting hole.