JPH0650439A - Mechanical seal leakage detector - Google Patents

Abstract

PURPOSE:To cope with a variety of mechanical seals with different liquid leakage of a mechanical seal leakage detector where the leaked liquid is stored in a storage tank to detect the rise of the liquid level and the leakage amount to be stored is constant. CONSTITUTION:A leakage amount adjusting external ring 34 is fitted into a storage tank 5 to store the leaked liquid from sliding surfaces 34a, 35a with a fixed ring 34 and a rotary ring 35 of a mechanical seal 23. The leaked liquid L lifts a diaphragm 7 to a constant height H, and actuates a microswitch 12 by a dog 11, and the leaked liquid amount in the storage tank 5 is adjusted by adjusting the number of the regulating external rings which are immersed in the liquid.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to means for detecting the amount of liquid leaking from a mechanical seal.

[0002]

2. Description of the Related Art Conventionally, mechanical seals are used to seal fluid shafts. Since the mechanical seal is designed to be sealed by the presence of the working fluid to be sealed on the sliding surfaces of the rotary ring and the fixed ring, it is necessary to prevent the working fluid from leaking from the rotary ring and the fixed ring to the outside. I can't. Therefore, a leakage liquid drain hole is provided on the outside of the fixed ring of the mechanical seal, and is guided to the leakage amount detector by piping.

FIG. 7 shows a conventional example. A leakage liquid drain hole 2 from a mechanical seal provided in the pump 1 is led to a leak amount detector 4 through a pipe 3. The leak amount detector 4 stores the leak liquid and emits a signal when the leak amount reaches a certain amount. The leaked liquid L is stored in the storage tank 5. The detection pipe 6 whose lower end is submerged in the leaked liquid L in the storage tank 5 communicates with a chamber member 8 supporting the diaphragm 7 and a diaphragm chamber 9 between the diaphragms 7 at the upper part. A dog 11 is fixed to the diaphragm 7, and when the dog 11 rises, the actuator of the microswitch 12 is pushed up to electrically connect the illustrated terminals A and C to urge the intervening buzzer 13. When the dog 11 is descending, the B and C terminals are electrically connected and the pilot lamp 14 is lit. The storage tank 5 is provided with an atmosphere communicating hole 15 at the top.

Now, when the leak liquid L is water,
The specific gravity is 1. The height of the water column at the operating point of the microswitch 12 is H. The head pressure P of the leaking liquid is 7 at atmospheric pressure.
Assuming 60 mmHg, 1 kg / cm ² = 10336 mmAq P = 1 kg / cm ² × H ÷ 10336 The difference H between the liquid levels in the storage tank 5 and the detection tube 6 is 80 mm, and the diameter of the diaphragm 7 is set so that the microswitch 12 operates. I have decided. The pressure at this time is P = 1 kg / cm ² × 80/10336 ≈0.0077 kg / cm ^2, which is a slight pressure. If the specific gravity of the liquid is different from that of water, adjust the height of the storage tank 5,
The characteristics of the diaphragm 11 are changed.

The micro switch 12 operates to operate the buzzer 1
When 3 is sounded, the liquid level in the storage tank 5 is at the set highest level, that is, the upper limit. Therefore, the valve 16 is opened to transfer the stored leaked liquid L to another container. When the valve 16 is opened, the liquid level of the leaked liquid L goes down, and the liquid level difference H becomes smaller. Therefore, the pressure applied to the diaphragm 7 goes down, the dog 11 goes down, the micro switch 12 switches, and the buzzer 13 stops ringing.
The pilot lamp 14 lights up. The valve 16 is closed while observing when the leaked liquid L in the storage tank 5 becomes empty.

[0006]

The amount of liquid leaking from the mechanical seal is predicted to vary depending on the type of liquid, the operating conditions of the pump 1, that is, the rotation speed, the discharge pressure, the pump structure, the mechanical seal structure and its performance, and the like. Since the amount of leaked liquid and the actual amount of leaked liquid often differ,
The storage tank tends to set a large volume of leaked liquid to be stored. If the actual amount of leaked liquid is significantly smaller than the predicted amount of leaked liquid, the buzzer will not ring forever, and it is impossible to determine whether or not there is a malfunction. Since the amount of leaked liquid differs in each case and varies over a wide range as described above, it is necessary to change the storage capacity if it is attempted to issue an alarm at an appropriate interval. Therefore, it is necessary to prepare many kinds of storage tanks 5, which is uneconomical. And to know the actual value of the leaked liquid, it is not the manufacturing process, but it is first known at the site where the pump is used.Therefore, replacement of the storage tank at that site must be done by obtaining a suitable storage tank from the manufacturer and replacing it. Instead, it takes time and effort.

In view of the above points, the present invention provides a leakage amount liquid detection device for a mechanical seal capable of measuring the amount of leakage liquid in a timely manner by adjusting the amount of leakage liquid stored at the site where the device is operated. Is intended.

[0008]

A first aspect of the present invention is to provide a storage tank for guiding and storing leaked liquid from a mechanical seal,
A detection tube which sinks a lower end below the liquid level in the storage tank and communicates with a diaphragm chamber whose upper part is partitioned by a diaphragm;
In a leak amount detector of a mechanical seal equipped with a switch that is activated by the deformation of the diaphragm due to the upper limit liquid level in the storage tank, the internal volume of the storage tank can be adjusted to make the storage amount variable. This is a leak detector for mechanical seals.

According to a second aspect of the present invention, the storage tank is upright and has a constant horizontal cross section, and the storage tank is made of a material having a specific gravity larger than that of the storage liquid and is fitted to the inner wall of the storage tank. The leak amount detector for a mechanical seal according to the first invention is characterized in that a leaked liquid amount adjusting outer ring mass is inserted.

A third aspect of the present invention is characterized in that the detection tube is upright, its horizontal cross section is constant, and a leak liquid amount adjusting inner ring mass fitted to the detector is attached. Is a leak amount detector for a mechanical seal according to the invention.

A fourth aspect of the present invention is characterized in that the storage tank contains the leakage liquid amount adjusting particles of a material having a specific gravity larger than that of the storage liquid, and the leakage amount of the mechanical seal according to the first invention. It is a detector.

A fifth invention of the present invention is characterized in that a leak amount detector for a mechanical seal according to the fourth invention is characterized in that the storage tank is provided with an insertion hole for inserting the leakage liquid amount adjusting particles and an extraction port for taking out the leakage liquid amount adjusting particles. Is.

A sixth aspect of the present invention is characterized in that a leakage liquid amount adjusting piston is fitted and fixed in the storage tank by opening the lower side of the storage tank and adjusting the position in the vertical direction. It is the leak amount detector of the mechanical seal described.

[0014]

Embodiments of the present invention will be described below with reference to the drawings.

[Embodiment 1] FIG. 1 is a vertical sectional view of an embodiment of the present invention. The leak amount detector 4 is as follows. The screw 5a is provided on the upper end portion of the cylindrical vertically long storage tank 5 and is screwed into the male screw 8a of the lower mounting portion of the chamber member 8 of the detection head 17, and the packing 18 between the chamber member 8 and the storage tank 5 is pressed. There is. Cover 19 of the detection head 17
A diaphragm 7 is sandwiched between the chamber member 8 and the chamber member 8 so as to be sandwiched and fixed between these members, and a diaphragm chamber 9 is provided between the diaphragm 7 and the chamber member 8. The detection tube 6 is fixed to the chamber member 8, and the lower end of the detection tube 6 is immersed in the leak liquid L accumulated in the storage tank 5. The micro switch 12 is housed and fixed in the cover 19 of the detection head 17. The actuator of the micro switch 12 faces the dog 11 fixed to the diaphragm 7, and when the dog 11 moves up, the micro switch 12 is pushed by the actuator to operate. The microswitch 12 is provided with a normally open contact 12NO, a normally closed contact 12NC, and a neutral terminal 12N, which are drawn out by lead wires to become A, B, and C terminals, respectively. Buzzer 13 between contact 12NO and terminal A
The pilot lamp 14 is interposed between the contact 12NC and the terminal B. A discharge port 5b is provided at the bottom of the storage tank 5, and a valve 16 is fixed to a discharge pipe 21 fixed to the discharge port 5b to discharge the leak liquid L in the storage tank 5.

An annular leak liquid amount adjusting outer ring mass 22 is fitted so as to fit into the inner wall of the storage tank 5. This outer ring 2
2 is made of a material having a heavier specific gravity than the leaked liquid L.

A leak liquid inlet 5c is provided in the upper portion of the storage tank 5, and a leak liquid drain hole of the cover casing 1C of the pump 1 is provided so as to communicate with the inlet 5c and the space 24 on the outlet side of the mechanical seal 23 of the pump 1. 2 and the pipe 3 are connected.

The pump 1 has a suction port 1A-1 and a discharge port 1A-.
An impeller 25 is housed in a casing body 1A provided with 2. The pump casing is integrally fixed by connecting the casing body 1A, the shaft sealing casing 1B, the cover casing 1C, and the bearing casing 1D in this order. Bearing 2 which also functions as a liner ring and is fitted in the shaft-sealed casing 1B
The pump shaft 28 is rotatably supported by 6 and the bearing 27 fitted in the bearing casing 1D. Pump shaft 28
The impeller 25 is fixed to one end of the motor and the electric motor shaft 31a of the electric motor 31 is fixed to the other end via a shaft coupling 29. The electric motor 31 is fixed to the bearing casing 1D. In order to prevent the pressurized liquid in the casing body 1A from flowing into the mechanical seal chamber 32, or to reduce the pressure applied to the mechanical seal chamber 32, before or after the bearing 26 also serving as the liner ring. A shaft sealing means (not shown) is provided. The mechanical seal 23 is fitted into the cover casing 1C via an O-ring 33, and is fixed to the shaft sealing casing 1B and the cover casing 1C. The fixed ring 34 is fixed to the sliding surface 34a of the fixed ring 34. And the pump shaft 2 via the O-ring 36.
8 is provided with a rotary ring 35 fitted axially movably, and a compression coil spring 38 compressed between the rotary ring 35 and a spring seat 37 fitted with the pump shaft 28. The spring seat 37 is provided with a cylindrical annular portion 37a, and a split stop ring 39 is fitted into the annular portion 37a. The stop ring 39 is fitted in the circumferential groove 28 a of the pump shaft 28.
A gland packing 41 is provided in the bearing casing 1D between the back space 24 of the mechanical seal and the bearing 27.

The operation of the above configuration will be described. When the electric motor 31 is rotated, the electric motor shaft 31a is rotated to rotate the shaft coupling 29.
To rotate the pump shaft 28. As a result, the impeller 25 rotates, sucks the working fluid from the suction port 1A-1, accelerates and pressurizes it, and discharges it from the discharge port 1A-2. The working fluid having a pressure applied to the back of the impeller 25 is prevented from flowing into the mechanical seal chamber 32 by a shaft sealing means (not shown).
When the working fluid is a liquid or gas having a high permeability and a high pressure, the same liquid as the working fluid is used for the mechanical seal chamber 32, and the shaft sealing device has the mechanical seal chamber 32.
Measure the decompression of. Sliding surfaces 34a, 35 of the mechanical seal
A small amount of the liquid leaks into the back space 24 of the mechanical seal 23 from between a. This liquid is sent to the storage tank 5 through the pipe 3. While the liquid level of the leaked liquid L is low, the pressure applied to the diaphragm chamber 9 is low, the displacement of the diaphragm 7 is small, the dog 11 is not pushing the actuator of the micro switch 12, the normally open contact 12NO is open, and the normally closed contact is open. 12NC is closed and pilot lamp 14
Is lit. When the liquid level of the leaked liquid L rises from the lower end of the detection tube 6 to the height H, the pressure in the diaphragm chamber 9 rises and pushes up the diaphragm 7, so that the dog 11 pushes up the actuator of the micro switch 12, and as shown in the figure, The closed contact 12NC is opened, the pilot lamp 14 is turned off, the normally open contact 12NO is closed, and the alarm buzzer 13 sounds. Thereby, the operator opens the valve 16 and collects the leaked liquid. Since the interval at which the alarm buzzer 13 sounds is determined by the liquid level rise time of the leak liquid in the storage tank 5, it can be adjusted by the number of the leak liquid amount adjusting outer ring mass 22 inserted into the storage tank 5. Therefore, if the reason why the interval at which the alarm buzzer 13 sounds is extremely long is such that the amount of liquid leaking from the mechanical seal 23 is small and the interval at which sounding is long is long, or if it is long due to a failure, the leaked liquid amount adjusting outer ring mass 22 By inserting, the time required for the leak liquid to accumulate in the storage tank 5 can be set to an appropriate time.

[Second Embodiment] FIG. 2 shows a second embodiment. Description of the same parts as those in the first embodiment will be omitted, and only different parts will be described. An annular leak liquid amount adjusting inner ring mass 45 having a short length in the longitudinal direction of the pipe 6 is fitted and fixed to the detection pipe 6. In this fitting method, a female screw is provided on the inner periphery of the leaked liquid amount adjusting inner ring mass 45 at least at the lowermost end, and a male screw with which the female screw is fitted is provided on the outer periphery of the detection tube 6. The liquid level of the leaked liquid L in the leaked liquid amount adjusting inner ring mass 45 rises and the microswitch 1
The operation interval of the microswitch 12 can be adjusted by adjusting the number within the height H shown in FIG.

FIG. 3 is a modification of FIG. A long male screw 6a is provided on the outer circumference of the detection tube 6, and a female screw 45a of the leaked liquid amount adjusting inner ring mass 45 is screwed into the male screw 6a. The inner ring mass 45 is one and is long in the longitudinal direction of the detection tube 6. Since the inner ring mass 45 moves up and down when the inner ring mass 45 is rotated, the amount of the leaked liquid L stored up to the head H in the storage tank 5 can be adjusted steplessly by the height of the submerged liquid.

[Third Embodiment] FIG. 4 shows a third embodiment. Description of the same parts as those in the first embodiment will be omitted, and different parts will be described. An L-shaped leak liquid amount adjusting ball insertion pipe 46 is attached to the upper part of the storage tank 5, and a leak liquid amount adjusting ball outlet is provided with a female screw so that the bottom of the storage tank 5 and the lower side of the hole are substantially aligned. Two 47 are provided on a straight line. A plug 48 is screwed into the outlet 47. The inner diameter of the leakage liquid amount adjusting sphere insertion pipe 46 and the valley diameter of the leakage liquid amount adjusting sphere outlet 47 are larger than those of the leakage liquid amount adjusting sphere 49. The leak liquid amount adjusting sphere 49 is made of a material that is heavier than the specific gravity of the leak liquid L and is selected so as not to be corroded by the leak liquid L.

When the leak liquid amount adjusting sphere 49 is inserted from the leak liquid amount adjusting sphere insertion pipe 46, the sphere 49 is accommodated in the bottom of the storage tank 5. The capacity of the leak liquid L in the storage tank 5 can be reduced by the number of the balls 49 inserted. In order to increase the amount of leaked liquid stored in the storage tank 5, the stopper 48 is removed, a rod-shaped object is inserted from one of the leaked liquid amount adjusting sphere outlets 47, and the leaked liquid amount adjusting sphere 49 is pushed to leak the other leak. It is performed by taking out from the liquid amount adjusting take-out port 47. Although the leakage liquid amount adjusting sphere 49 is spherical, the same effect can be obtained even if the shape is different as long as it is not limited to a sphere.

[Fourth Embodiment] FIG. 5 shows a fourth embodiment. Description of the same parts as those in the first embodiment will be omitted, and different parts will be described. A leak liquid amount adjusting piston 51 is fitted in the storage tank 5 so that the vertical position of the storage tank 5 can be adjusted, and an O-ring 52 fitted between the piston 51 and the storage tank 5 in a circumferential groove of the piston 51. It is sealed by. This Biston 51
Is fixed to the storage tank 5 by, for example, a set screw 53 screwed across the storage tank 5. In this embodiment, if a vertical scale is provided on the outer circumference of the leakage liquid amount adjusting piston 51, the adjustment amount can be adjusted from the outside and the adjustment amount can be visually checked.

FIG. 6 shows a modification of the fourth embodiment. The allowable leakage amount of the mechanical seal specified in Japanese Industrial Standard is, for example, 3c. c. / H. In such a case, in order to make the alarm buzzer 13 sound once an hour, as shown in FIG.
In, the space for the leak liquid stored between the detection pipe 6 and the piston 51 becomes small, and the gap between the detection pipe 6 and the inner diameter of the piston 51 may become too small. Therefore, FIG.
As described above, the inner diameter of the piston 51 is made equal to the outer diameter of the detection pipe 6, and the small hole 54 in the axial direction and the small hole 55 in the radial direction are formed in the piston 51 so that the space 56 between the bottom on the inner diameter side of the piston 51 and the detection pipe 6 is formed. And the upper space 57 of the storage tank 5 are connected. In this way, since the volumes of the small holes 54 and 55 and the internal volume of the drain pipe 21 are small, the amount of the leaked liquid L stored before the alarm buzzer 13 sounds can be reduced.

According to the first and second embodiments, the leakage liquid L in the storage tank 5
In order to adjust the amount, the storage tank 5 must be separated from the detection head 17, but according to the third embodiment, the stored amount of leaked liquid can be adjusted without disassembling the leak amount detector.

[0027]

According to the present invention, a storage tank for guiding and storing a leaked liquid from a mechanical seal, and a detection tube for sinking a lower end below the liquid level in the storage tank and communicating with a diaphragm chamber whose upper part is partitioned by a diaphragm are provided. In a leak amount detector of a mechanical seal equipped with a switch that is activated by the deformation of the diaphragm due to the upper limit liquid level in the storage tank, the internal volume of the storage tank can be adjusted to make the storage amount variable. Since it is a mechanical seal leak detector,
The amount of leaked liquid in the mechanical seal stored in the storage tank can be adjusted, so that the time for the leaked liquid to be stored in the storage tank can be set at an appropriate interval. Therefore, for example, the buzzer interval of the alarm means can be set to an appropriate interval, and when the mechanical seal is oil-filled, the oil can be replenished in a timely manner. or,
By providing a means for recording or recording the interval at which the alarm buzzer sounds, there is a ripple effect that the degree of deterioration of the mechanical seal can be known.

When the leaked liquid amount adjusting outer ring mass is put in the storage tank, the storage tank is simply removed and the outer ring mass is put in, and the stored leaked liquid amount can be easily adjusted. Further, since the outer ring mass is housed in the outer peripheral part of the inner rectangle of the storage tank, the amount of stored liquid can be greatly adjusted.

When the leaked liquid amount adjusting inner ring mass is attached to the detection tube, the storage tank is simply removed and the inner ring mass is attached to the detection pipe. or,
Since the inner ring mass is housed in the center of the inner rectangle of the storage tank, the amount of liquid stored can be finely adjusted.

When the leak amount adjusting particles are stored in the storage tank, the leak liquid amount can be adjusted in units of the particles.

If the storage tank is provided with an insertion hole for inserting the leakage liquid amount adjusting particles and an outlet for taking out the leakage liquid amount adjusting particles, the storage amount can be adjusted without disassembling the apparatus.

If a leakage amount adjusting piston is provided in the storage tank so that the position can be adjusted in the vertical direction, the amount of liquid stored can be adjusted from the outside, and the amount by which the piston moves up and down can be known by marking the scale. , It is possible to grasp the stored amount quantitatively.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of a first embodiment of the present invention.

FIG. 2 is a vertical sectional view of a second embodiment of the present invention.

FIG. 3 is a vertical sectional view of a modified example of the second embodiment.

FIG. 4 is a vertical sectional view of a third embodiment of the present invention.

FIG. 5 is a vertical cross-sectional view of Embodiment 4 of the present invention.

FIG. 6 is a vertical sectional view of a modified example of the fourth embodiment.

FIG. 7 is a vertical sectional view of a conventional example.

[Explanation of symbols]

 1 Pump 2 Leakage liquid drain hole 3 Piping 5 Storage tank 6 Detection pipe 22 Leakage liquid amount adjusting outer ring mass 23 Mechanical seal 45 Leakage liquid amount adjusting inner ring mass 46 Leakage liquid amount adjusting ball insertion pipe 47 Leakage liquid amount adjusting ball outlet 48 Stopper 49 Leakage liquid amount adjusting ball 51 Leakage liquid amount adjusting piston 53 Set screw

Claims (6)

[Claims] 1. A storage tank for guiding and storing a leaked liquid from a mechanical seal, a detection tube for sinking a lower end below a liquid surface in the storage tank, and a detection tube communicating with a diaphragm chamber partitioned by a diaphragm at an upper portion, and the storage tank. In a leak amount detector of a mechanical seal equipped with a switch that is activated by the deformation of the diaphragm due to the upper limit liquid level inside, the mechanical seal is characterized in that the internal volume of the storage tank is adjustable and the amount of stored liquid is variable. Leakage amount detector. 2. The storage tank is upright, has a constant horizontal cross section, is made of a material having a specific gravity larger than that of the storage liquid, and is fitted with an inner wall of the storage tank. The leak amount detector of the mechanical seal according to claim 1, wherein a lump is inserted. 3. The mechanical seal according to claim 1, wherein the detection tube is upright, its horizontal cross section is constant, and a leak liquid amount adjusting inner ring mass fitted to the detection tube is attached. Leakage amount detector. 4. The leak detector for a mechanical seal according to claim 1, wherein the storage tank contains leak liquid amount adjusting particles of a material having a specific gravity larger than that of the storage liquid. 5. The leak amount detector of the mechanical seal according to claim 4, wherein the storage tank is provided with an insertion hole for inserting the leak liquid amount adjusting particles and a take-out port for taking out the leak liquid amount adjusting particles. 6. The leak amount of the mechanical seal according to claim 1, wherein a leakage liquid amount adjusting piston is fitted and fixed in the storage tank such that the lower portion of the storage tank is opened and the position thereof can be adjusted in the vertical direction. Detector.