JPH11258115A - Valve packing testing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To allow accurate performance evaluation of a valve packing while various characteristics values are measured under such condition as spiral movement applied. SOLUTION: The performance of a valve packing as a sample set inside a pressure vessel is evaluated. Here, a spiral motion applying means for applying spiral motion to a shaft 28 which is inserted, in sliding/contact state, in a valve packing 23 set inside the pressure vessel 3, a pressure control means which keeps the pressure in the pressure vessel 3 constant, and a measuring means which at least measures a load in axial direction of the shaft 28 at spiral motion, are provided. The spiral motion applying means comprises a ball spline axis 5 connected to the shaft 28 through a coupling, a linear drive cylinder 10 for linear movement of the shaft 5, and a revolution-driving motor 9 for rotational movement of the axis 5, while the pressure control means comprises a pressure-controlling pressure vessel 13 of the same shape as the pressure vessel 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a test apparatus for evaluating the performance of a valve packing of a high-temperature and high-pressure valve used in, for example, a power plant, and more particularly to a valve packing test apparatus capable of accurately evaluating the performance of a valve packing. About.

[0002]

2. Description of the Related Art A conventional test apparatus of this type is, for example, shown in FIG.
As shown in the figure, the valve packing 23 is set on both sides of the pressure vessel 101 via the holding flange 108, and the load cell 1 is disposed between the shaft 102 and the cylinder 103.
In addition, a heater 104 for increasing the temperature is arranged outside the pressure vessel 101. Further, the pressure vessel 101 is configured to be supplied with high-pressure water from a water supply tank 106 via a boost pump 107. And
The performance of the valve packing 23 is evaluated by moving the shaft 102 linearly by the operation of the cylinder 103 and measuring the total value of the frictional resistance between the valve packing 23 on both sides and the shaft 102 with the load cell 104.

[0003]

However, in this test apparatus 100, the cylinder 103
02 reciprocates, the volume inside the pressure vessel 101 does not change, so that the advantage that the fluctuation of the internal pressure is small and the pressure control is simple is obtained, but it is difficult to accurately measure the performance of the valve packing 23. There was a problem that it is. That is, the load measured by the load cell 104 is measured as the sum of the axial load due to the internal pressure in the pressure vessel 101 and the frictional force with the valve packings 23 provided on both sides of the shaft 102.

However, in the test apparatus 100 described above, since the valve packings 23 are provided on both sides of the pressure vessel 101, the frictional force of the valve packings 23 measured by the load cell 104 is reduced by the two valve packings 23. Therefore, the frictional resistance between the individual valve packing 23 and the shaft 102 cannot be measured accurately.

The valve packing 23 and the shaft 102
Is a very important value in evaluating the performance of the valve packing 23. Particularly, in the case of a valve packing such as a globe valve used in a high-temperature and high-pressure state and performing a spiral movement, the measured value is immediately It was not possible to obtain an accurate evaluation of the valve
In fact, the appearance of a test apparatus capable of appropriately evaluating the performance of No. 3 is desired.

SUMMARY OF THE INVENTION The present invention has been made in view of such circumstances, and an object of the present invention is to measure various characteristic values in a state in which a helical motion is provided, and to provide a valve. An object of the present invention is to provide a valve packing test device capable of performing accurate performance evaluation of a packing.

[0007]

In order to achieve the above object, an invention according to claim 1 of the present invention is a test apparatus for evaluating the performance of a valve packing as a sample set in a pressure vessel. A spiral motion imparting means capable of imparting a spiral motion to a shaft fitted in sliding contact with a valve packing set in the pressure vessel, a pressure control means capable of maintaining a constant pressure in the pressure vessel, and at least a shaft. And a measuring means for measuring an axial load at the time of the spiral movement.

[0008] With this configuration, the valve packing as a sample set in the pressure vessel in a state of sliding contact with the shaft makes a spiral movement by the operation of the spiral movement applying means, and the pressure vessel accompanying the spiral movement. The pressure in the pressure vessel is kept constant while the pressure fluctuation in the pressure vessel is controlled by the pressure control means. In this state, the load in the axial direction of the shaft is measured by the measuring means,
The frictional resistance between the shaft and the valve packing is calculated, and the performance of the valve packing is evaluated. Since the performance of the valve pan is evaluated not in a linear motion but in a helical motion, accurate performance evaluation corresponding to the motion of the valve is possible even for a valve that performs a helical motion such as a globe valve. .

According to a second aspect of the present invention, the helical motion imparting means includes a ball spline shaft connected to the shaft via a coupling, a linear drive cylinder for linearly moving the shaft, and a rotational motion for the shaft. And a helical motion is imparted to the shaft by simultaneously operating the linear drive cylinder and the rotary drive motor. With such a configuration, by simultaneously operating the linear drive cylinder and the rotary drive motor, it is possible to impart a spiral motion to the shaft via the ball spline shaft. A stable spiral motion is obtained,
More accurate performance evaluation of the valve packing becomes possible.

The invention according to claim 3 is characterized in that the shaft is slidably inserted into a pallet packing set in the pressure vessel without penetrating the pressure vessel. With this configuration, since the shaft does not penetrate the pressure vessel, the shaft can be slid in contact with one valve packing set in the pressure vessel. Resistance can be measured accurately, and more accurate performance evaluation of the valve packing becomes possible.

According to a fourth aspect of the present invention, the pressure control means has a pressure control pressure vessel having the same shape as the pressure vessel, and the volume of the pressure control pressure vessel changes with the pressure fluctuation in the pressure vessel. It is characterized in that the pressure in the pressure vessel is kept constant by following and fluctuating. With this configuration, for example, when the volume in the pressure vessel increases, the volume in the pressure control pressure vessel having the same shape decreases following the increase,
With a relatively simple configuration, the pressure in the pressure vessel can be always kept constant, and more accurate performance evaluation of the valve packing becomes possible.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below in detail with reference to the drawings. 1 to 5 show an embodiment of a valve packing test apparatus according to the present invention,
1 is a schematic front view, FIG. 2 is a plan view, FIG. 3 is an enlarged front view of a pressure vessel portion, FIG. 4 is a schematic system diagram of piping, and FIG. 5 is a process diagram showing an example of a test method.

1 and 2, the test apparatus 1 has a frame 2 formed in a frame shape.
A pressure vessel 3 movable by a slide mechanism (not shown) in the directions of arrows A and B in FIG. 1 is disposed. One end of a ball spline shaft 5 is connected to the left end side of the flange 4 of the pressure vessel 3, and a thrust joint 6 is connected to the other end of the ball spline shaft 5 and a gear 7 is fixed.

As shown in FIG. 2, a rotary drive motor 9 having a torque converter is connected to the gear 7 through a belt 8, and a thrust joint 6 is connected to a cylinder shaft 10a of a linear drive cylinder 10. Are connected via a load cell 11 as one of the measuring means. The rotation driving motor 9, the linear driving cylinder 10, the ball spline shaft 5, and the like constitute a spiral motion applying means.

As shown in FIG. 1, a pressure control pressure vessel 13 constituting pressure control means and a linear drive cylinder 14 for driving the pressure vessel 13 are arranged below the mount 2, as shown in FIG. As will be described later, an electronic balance 15, a pressure gauge 16, an accumulator 17, a water supply tank 18, a booster pump 19, a hydraulic unit 20, and the like for measuring a leak amount are arranged. 1 and 2
In the figure, reference numeral 21 indicates an inverter, and reference numeral 22 indicates a panel attached to the entire peripheral surface of the gantry 2.

The pressure vessel 3 in which the valve packing 23 as a sample is set has a body 26 connected with a high-pressure side flange 25, the flange 4 and a holding flange 27 as shown in an enlarged view in FIG. The shaft 28 is inserted into a hole provided inside the body 26 and the flange 4 without penetrating the pressure vessel 3. A portion of the shaft 28 corresponding to the hole of the flange 4 includes a ring 2
9, for example, a valve packing 2 supplied by a customer.
3 is fitted.

A holding flange 27 is connected to the flange 4 by a bolt 30. A load cell 31 and a cooler 32 are attached to the holding flange 27 on the flange 4 side, and a leak detecting port 33 is provided on the flange 4. Have been. The ball spline shaft 5 is connected via a coupling 34 to a shaft 28 projecting to the left end side of the holding flange 27.

Further, a pipe joint 35 communicating with a hole inside the body 26 is attached to a tip (right end) side of the body 26, and a valve packing 23 of the pressure vessel 3 is provided.
The heaters 36 and 37 are disposed on the side of the position where the is set and on the slide mechanism (not shown) on the side of the body 26. The pressure control pressure vessel 1
3, a shaft 38 is connected to a cylinder shaft 14 of a linear drive cylinder 14 via a coupling 39, as shown in FIG.
Since the pressure vessel 3 is formed in the same manner as the pressure vessel 3 except that it is directly connected to a, the detailed description thereof is omitted.

Next, the connection state of the piping system of the test apparatus 1 will be described with reference to the schematic system diagram of FIG. An initial water supply port 42 is connected to a pipe joint 35 of the pressure vessel 3 through a valve 41.
Is connected, and the steam outlet 44 is connected via the safety valve 43.
Is connected. Further, the pipe joint 35 is connected to the pipe joint 35 of the pressure vessel 13 for pressure control and the water supply pipe 45.

The water supply pipe 45 has the water supply tank 18 at the most upstream side thereof. The water supply tank 18 is connected to a booster pump 19 via a valve 46, and the booster pump 19 is connected to the water supply tank 18 via a valve 47. Piping joint 35 of pressure vessel 3
It is connected to the. Further, the pressure gauge 16, the pressure transducer 48, and the rupture plate 49 are connected to the water supply pipe 45, and the accumulator 17 is connected via a valve 50.

A cooling pipe 52 is connected to the leak detection port 33 of the pressure vessel 3, and a lower portion of the cooling pipe 52 is connected to the electronic balance 15. The cooling pipe 52 has an inlet connected to a cooling water inlet 54 via a valve 53, and an outlet connected to a cooling water outlet 55. The cooling water inlet 54 is connected to the inlet side of the cooler 32 of the pressure vessel 3 and the pressure control pressure vessel 13 via a valve 56, respectively.
2 are connected to the outlet side.

On the other hand, the linear drive cylinders 10 and 1 for operating the pressure vessel 3 and the pressure control pressure vessel 13
Reference numeral 4 denotes a flow regulator 58, a pilot lamp 59, and a solenoid valve 6 via a base block 57.
0 and the hydraulic unit 20
It is connected to the. The operation of the hydraulic unit 20 and the solenoid valve 60 causes the linear drive cylinder 1
0 and 14 are driven, and their cylinder shafts 10a and 14a move linearly, respectively. In the above example, the linear movement of the pressure vessel 3 and the pressure control pressure vessel 13 is performed by the hydraulic drive method. However, other appropriate linear drive methods such as pneumatic pressure and a combination of an electric motor and a ball screw are used. Can also be adopted.

Next, an example of a test method of the valve packing 23 by the test apparatus 1 will be described with reference to a process chart of FIG. First, when the valve packing 23 already measured is set in the test apparatus 1, the bolt 30 of the holding flange 27 is removed, the pipe joint 35 is removed, and the flange 4, the heaters 36 and 37, the body 26, and the high-pressure flange 25 are removed. Is moved in the direction of arrow A for each slide mechanism, and the shaft 28 is pulled out of the flange 4. Then, the ring 29 and the valve packing 23 are removed from the flange 4. As a result, the valve packing 23 for which measurement has been completed is
Removed from

After the valve packing 23 having been measured is removed, the next new sample, the valve packing 23 and the ring 29 are inserted into the flange 4 (K101), and the pressure vessel 3 and the like are moved in the direction of arrow B for each slide mechanism (K101). K10
2) and tighten the bolt 30 (K103). At this time, the tightening torque of the bolt 30 is managed by the load cell 31 according to the characteristics of the valve packing 23. Then, the pipe to the cooler 32, the pipe to the leak detection port 33, and the pipe joint 3
5 is attached (K104). This allows
The sample setting is completed.

When the setting of the sample is completed, the heaters 36, 3
7 (K105), the body 26 and the flange 4
Is heated to a predetermined temperature. At this time, cooling water is supplied to the cooler 32 (K106) so that the load cell 31 does not reach the limit temperature, and the load cell 31 is cooled. After the operation of the heaters 36 and 37 and the temperature raising step by the supply of the cooling water are completed, the valve 41 is opened and water is injected from the initial water supply port 42 (K107). The water injection amount at this time is determined from the steam table data depending on the target temperature and pressure.

Then, after injecting water, the pressurizing pump 1
9 is driven (K108) to increase the internal pressure of the pressure vessel 3. The internal pressure at this time is controlled by the signal of the pressure transducer 48. Note that since the space between the water supply tank 18 and the valve 46 is not heated, the water in the water supply pipe 45 is in a liquid state due to high pressure, and the accumulator 17 and the pressure converter 4
8. There is no need to use heat-resistant pumps 19 and the like. Also, the internal pressure change due to the pulsation change of the booster pump 19 and the temperature rise can be absorbed by the accumulator 17 and the pressure in the piping system becomes constant. However, even if the pressure rises excessively, the safety valve 43 The rupture plate 49 operates to prevent an abnormal increase in pressure.

When the temperature and pressure become constant by the temperature raising step and the pressure increasing step, the process proceeds to the measuring step. In this measurement step, first, the linear drive cylinder 10 is operated (K109) by the hydraulic unit 20 and the solenoid valve 60 to linearly move the cylinder shaft 10a, and the belt 8 is moved through the gear 7 outside the ball spline shaft 5. Then, the rotation driving motor 9 connected in step (1) is driven (K110), and the ball spline shaft 5 is rotated. The rotation speed at this time is
Set arbitrarily according to the number of closing times of the globe valve of the actual machine.

The ball spline shaft 5 and the cylinder shaft 10a of the linear drive cylinder 10 are connected via a thrust joint 6 (K111), whereby linear motion and rotational motion are simultaneously performed, and the motion of the shaft 28 is controlled. It becomes a spiral movement. The spiral movement of the shaft 28 is continuously performed by a timer or a counter (not shown).
The moving speed of the shaft 28 is set to about 300 to 1000 mm / min based on the movement of the valve stem of the actual machine.

Then, the load applied to the ball spline shaft 5 during the spiral movement is measured by the load cell 11, and the rotational torque is measured by a torque converter (not shown) in the rotary drive motor 9 (K112). By measuring the load and the rotation torque, the frictional resistance of the valve packing 23 is calculated.

By the way, when the shaft 28 moves, the volume of the space inside the body 26 greatly changes, so that the internal pressure fluctuates. This fluctuation of the internal pressure is controlled by the pressure vessel 13 for pressure control. That is, the pressure control pressure vessel 13 is set to have the same volume as the pressure vessel 3, and the linear drive cylinders 10, 14 are interlocked with each other in accordance with the fluctuation of the internal pressure of the pressure vessel 3 to perform linear motion (one of them is extended). Then the other retreats). The fluctuation of the internal pressure in the pressure vessel 3 is controlled by the fluctuation of the volume in the pressure control pressure vessel 13, and is always maintained at a constant internal pressure.

After the load and the rotation torque are measured, the amount of leakage is measured (K113). The measurement of this leakage is
When the performance of the set valve packing 23 is deteriorated or the initial tightening is insufficient, the steam leaked from the leak detection port 33 is solidified in the cooling pipe 52 and measured by the electronic balance 15. The leakage amount is also important data for evaluating the performance of the valve packing 23.

After a continuous operation for a certain period (one to several days), the temperature and pressure in the pressure vessel 3 are lowered, the valve packing 23 is taken out (K114), and necessary data (shaft load, rotation torque, tightening) are obtained. The torque, leakage amount, temperature, pressure, etc.) are taken into the recorder (K115), and the test of the valve packing 23 ends.

In the above steps, the pressure vessel 3
Although the pressure was increased after the inside was heated, the temperature may be increased after the pressure is increased, or the pressure vessel 1 for pressure control may be heated.
3, a rotating mechanism similar to that of the pressure vessel 3 may be provided to evaluate the performance of the two types of valve packings 23 in one test.

As described above, in the test apparatus 1 of the above embodiment, the linear drive cylinder 10 and the rotary drive motor 9
Is provided, it is possible to measure data important for performance evaluation of the valve packing 23 such as a shaft load, a rotating torque, and a tightening torque in a state where the shaft 28 performs a spiral motion. Valve packing 23
Can be accurately evaluated. In particular, when the shaft 28 is not penetrated into the pressure vessel 3, the valve packing 2
3, the valve packing 23 and the shaft 28 can be made to correspond one to one, so that the frictional resistance of each valve packing 23 can be accurately measured.

Further, the pressure vessels 3 having the same shape are provided side by side in the pressure vessel 3 and they are linked by separate linear drive cylinders 10 and 14, respectively. When the pressure is being pushed, the pressure control pressure vessel 13 side is pulled, so that the total volume in the two pressure vessels 3 and 13 can always be kept constant, and the pressure fluctuation in the pressure vessel 3 can be eliminated. From these facts, it is possible to perform high-precision performance evaluation corresponding to the movement of the actual machine, even for valve packing in which the stem moves spirally, such as globe valves that are frequently used especially in power plants. Become.

Further, since the helical motion can be imparted to the shaft 28 by the rotary drive motor 9, the linear drive cylinder 10, the ball spline shaft 5, and the like, no special parts are required. By making the configuration relatively simple, it is possible to cause the shaft 28 to perform a stable spiral movement. Further, since the pressure in the pressure vessel 3 can be kept constant by the pressure control pressure vessel 13 and the linear drive cylinder 14 having the same shape, the structure of the pressure control means can be compared, for example, the parts can be shared. Can be simplified.

Also, for example, if the pressure control pressure vessel 13 is made to perform the same spiral movement as the pressure vessel 3, the performance of the two types of valve packings 23 can be evaluated in one test. Efficiency can be improved.

FIG. 6 is a schematic configuration diagram of a main portion showing another embodiment of the test apparatus according to the present invention. The same parts as those of the test apparatus 1 of the above embodiment are denoted by the same reference numerals, and detailed description thereof will be omitted. The features of the test apparatus 1 of this embodiment are as follows.
A cooler 64 and a heater 65 are connected to a pipe joint 35 of the pressure vessel 3 via check valves 62 and 63, and between the heater 65 and the cooler 64, an accumulator 17, a booster pump 19, and water supply are provided. Water supply pipe 45 composed of tank 18 and the like
Are connected.

According to the test apparatus 1, the pressure fluctuation in the pressure vessel 3 can be eliminated without providing the pressure control pressure vessel 13, and the same operation and effect as those of the above embodiment can be obtained. , Normal cycle (1-2 minutes)
Although the selection of the performance of the cooler 64 and the heater 65 becomes somewhat difficult in order to maintain the heat balance, the operation and effect of reducing the cost can be achieved by simplifying the configuration of the test apparatus 1. can get.

In the above-described embodiment, the case where the performance of the valve packing 23 which makes a helical motion like a globe valve for high temperature and high pressure is evaluated has been described as an example, but the present invention is not limited to this. However, it can also be used for performance evaluation of general valve packing, for example. In this case, for example, the performance of the valve packing 23 can be evaluated only by operating the linear drive cylinder 10 without driving the rotary drive motor 9.

The shapes of the pressure vessel 3 and the pressure vessel 13 for pressure control in the above embodiment, the arrangement structure and piping system diagram of the whole components of the test apparatus 1, the test process diagram shown in FIG. It goes without saying that various modifications can be made without departing from the spirit of the present invention.

[0042]

As described in detail above, claims 1 to 4
According to the described invention, while applying a spiral motion to the shaft in sliding contact with the valve packing, while maintaining the pressure in the pressure vessel constant, the axial load of the shaft and the like are measured, for example, The frictional resistance between the shaft and the valve packing is accurately calculated, and the performance of the valve packing can be evaluated with high accuracy.

[Brief description of the drawings]

FIG. 1 is a schematic front view showing one embodiment of a valve packing test apparatus according to the present invention.

FIG. 2 is a plan view of the same.

FIG. 3 is an enlarged front view of the pressure vessel portion.

FIG. 4 is a schematic system diagram showing a state of the piping.

FIG. 5 is a process chart showing an example of the test method.

FIG. 6 is a schematic configuration diagram of a main part showing another embodiment of the valve packing test apparatus according to the present invention.

FIG. 7 is a sectional view of a main part showing a conventional test apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Test apparatus 3 Pressure vessel 4 Flange 5 Ball spline shaft 6 Thrust joint 9 Rotary drive motor 10 Linear drive cylinder 11 Load cell 13 Pressure control pressure vessel 14 Linear drive cylinder 15 Electronic balance 23 Valve packing 25 High pressure side flange 26 Body 27 Holding flange 28 Shaft 29 Ring 30 Bolt 31 Load cell 32 Cooler 33 Leakage detection port 35 Pipe joint 36, 37 Heater 45 Water supply pipe

Claims (4)

[Claims] 1. A test device for evaluating the performance of a valve packing as a sample set in a pressure vessel, wherein a helical movement is made on a shaft fitted in sliding contact with the valve packing set in the pressure vessel. And a pressure control means capable of maintaining a constant pressure in the pressure vessel, and a measuring means capable of measuring at least an axial load during the spiral movement of the shaft. A valve packing test device, characterized in that: 2. A ball spline shaft connected to the shaft via a coupling, a linear driving cylinder for linearly moving the shaft, and a rotary driving motor for rotating the shaft. 2. The valve packing test apparatus according to claim 1, wherein the shaft packing is provided with a spiral movement by simultaneously operating a linear drive cylinder and a rotary drive motor. 3. The shaft according to claim 1, wherein the shaft is slidably fitted into a pallet packing set in the pressure vessel without penetrating the pressure vessel.
The described valve packing test apparatus. 4. The pressure control means has a pressure vessel for pressure control having the same shape as the pressure vessel, and the volume of the pressure vessel for pressure control fluctuates following the fluctuation of the pressure in the pressure vessel. 2. The valve packing test apparatus according to claim 1, wherein the pressure inside the pressure vessel is kept constant by the pressure.