JPH0159532B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for inspecting leaks in pipelines.

At gas stations, there is piping that connects the underground oil storage tank with the above-ground refueling equipment, but since this piping is buried underground or in the walls of buildings, leakage detection requires It requires some ingenuity.

Previously, the presence or absence of a leak was determined by sealing both ends of the piping, injecting compressed air, and observing the pressure change, but this method had the drawback of requiring a lot of time and expense for inspection. It was hot.

In view of the above points, the present invention displays a pump, a flow meter connected to the secondary side of this pump, a liquid supply pipe connected to the secondary side of this flow meter, and a liquid amount measured by the flow meter. a liquid supply device including a display, a liquid storage tank, and a communication pipe connecting the primary side of the pump and the liquid storage tank and having a check valve inserted near the liquid storage tank; In the liquid supply system, the liquid pumped from the liquid storage tank by the pump is supplied via the liquid supply pipe, (a) connecting the communication pipe to a primary side connection part of the pump; (b) connecting the liquid supply pipe to the communication pipe via a return pipe on the side of the liquid storage tank at the closed or cutoff position; (c) A method for inspecting a pipe line is proposed, which comprises the steps of: operating the pump to increase the secondary side pressure of the pump; and transmitting this liquid pressure to the connecting pipe line via the return pipe line. .

If the connecting pipe does not have a check valve, it is necessary to close or cut off the connecting pipe from the liquid storage tank in the vicinity of the liquid storage tank before performing the above step (c).

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

In Figure 1, G is the land of the gas station, 1 is the refueling system installed on the ground, 2 is the oil storage tank buried underground, 4 is the manhole, and 5 is the connection connecting the refueling system 1 and tank 2. The pipe (oil suction pipe) 3 is a check valve inserted into the communication pipe 5 near the outlet of the tank 2.

The refueling device 1 is of a ground-mounted type, and 7 is a refueling pipe connected to the connecting pipe 5 on the primary side. 8 is a check valve, 9 is an oil supply pump, 10 is a pump motor, 1
1 is a bypass pipe connected to the oil feed pipe 7 on the primary and secondary sides of the pump 9; 12 is a relief valve inserted in the bypass pipe 11; and 13 is a bypass pipe inserted in the oil feed pipe 7 on the secondary side of the pump 9. 14 is a flow meter inserted into the oil pipe 7 on the secondary side of the air separator 13;
5 is a flow rate pulse transmitter that generates an electric pulse (flow rate pulse) according to the amount of oil measured by the flow meter 14;
A hose 16 is connected to the secondary end of the oil pipe 7, and the secondary end portion 7' of the oil pipe 7 and the hose 16 constitute a liquid supply pipe. 17 is a refueling nozzle connected to the tip of the hose 16.

18 is a nozzle hook provided on the side wall of the housing of the oil supply device 1, and 19 is a nozzle switch provided inside the case of the nozzle hook 18, which is operated in response to the operation of hooking and unhooking the nozzle 17 to the nozzle hook 18, and generates a nozzle signal. ,Extinguish. 20 is a control circuit, 2
Reference numeral 1 denotes an indicator for the amount of oil to be supplied, etc., which returns to zero when the nozzle signal from the nozzle switch 19 disappears when the nozzle 17 is removed from the nozzle case 18.

The air separator 13 consists of an air separation chamber 13a and a float chamber 13b, and 13c consists of both chambers 13a and 13.
A communication hole provided in the partition wall b, 13d a pipe communicating the float chamber and the bypass pipe 11 of the pump 9,
13e is a float, 13f is a valve operated by the float 13e to open and close the pipe 13d, 13g is a ventilation pipe,
13h is an oil supply port.

The normal lubrication operation of the lubrication device as described above is well known, so a description thereof will be omitted.

The following members are provided to carry out the method of the present invention. That is, V _a is a valve inserted in the connection between the secondary end of the communication pipe 5 and the primary end of the oil feed pipe of the oil supply device 1, and RP is the secondary side (liquid supply pipe) of the flow meter 14. A return pipe, V _b , which connects the and the communication pipe 5 on the primary side of the valve V _a .
is a valve inserted in the return pipe RP. Further, RS is a reset (return to zero) switch for the display 21, which is used to reset the display 21 other than by removing the nozzle 17 from the nozzle case 18.
In addition, if there is no check valve 3 near the tank 2, the valve
V _c or other means of closing or shutting off the connecting pipe 5 in the vicinity of the tank 2 are required.

When using lubrication device 1 for normal lubrication, close the valve
V _a (and V _c ) are open and valve V _b is closed.

When performing a leakage test, valve V _a (and V _c ) is closed (step (a)) and valve V _b is opened (step (b)). When the nozzle 17 is removed from the nozzle case 18, the motor 10 is energized and the pump 9 is driven, increasing the pressure inside the oil feed pipe 7 on the secondary side of the pump 9, and this pressure is transmitted to the inside of the hose 16. Other return pipe
It is also transmitted to the connecting pipe 5 via the RP (step (c)). At this time, the oil in the communication pipe 5 is not returned to the tank 2 because of the check valve 3 (or the closed valve V _c ).

However, since the hose 16 has elasticity and swells, the flowmeter 14 measures the amount of oil corresponding to the swell of the hose, and the measured value is displayed on the display 21. However, if there is no leakage from the connecting pipe 5, oil will be measured by the amount of oil that swells. No weighing is done. Therefore, when the measured value of the known hose expansion is displayed, by pressing the reset switch RS to return the display 21 to zero and monitoring the display 21 for a while, it is possible to know whether there is a leak.

If there is no switch RS, in order to reset the display of the hose expansion, temporarily return the nozzle 17 to the nozzle case 18 and return the display 21 to zero.
The pump 9 may be restarted by removing the nozzle from the nozzle case again. Of course, the displayed value of the hose expansion may be memorized or recorded without performing such an operation.

If necessary, oil is supplied from the oil supply port 13h of the air separator 13 using the oil shovel 22 before or during the inspection.

FIG. 2 shows another construction of a refueling device suitable for carrying out the method of the invention, in which the same reference symbols as in FIG. 1 indicate corresponding parts.

In FIG. 2, the valves V _a and V _b in FIG. 1 have been replaced by a three-way valve V _d . This three-way valve V _d
are the communication pipe 5, the oil supply pipe 7 in the oil supply device 1, and the return pipe.
It constitutes a connection part with the RP, and an example of a specific structure is shown in FIGS. 3a to 3c.

That is, 30 is a spherical valve casing, 31 is a spherical valve body built into the casing, 32 is a large-diameter through-flow passage that penetrates the spherical valve body 31 in the diametrical direction, and 33 is connected to the large-diameter through-flow passage in a T-shape. It is a small diameter flow path.

When the oil supply device 1 is in use for normal oil supply, the spherical valve body 31 of the three-way valve _Vd is in the position shown in FIG. RP is closed to the pump primary side of the oil feed pipe 7 and the communication pipe 5.

When inspecting for leakage, check the spherical valve body 31 as shown in Figure 3a.
When the return pipe RP is rotated clockwise from the position shown in Fig. 3b and stopped at the position shown in Fig. 3c,
are the large-diameter flow passage 32 and the small-diameter flow passage 33 of the valve body 31.
Although it communicates with the communication pipe 5 through the oil supply pipe 7, it is cut off from the pump primary side of the oil supply pipe 7.

In the configuration shown in Figure 1, if valve V _b is left open intentionally or inadvertently for fraudulent purposes under normal conditions, some of the oil that has been metered will not be refilled and will flow through the return pipe RP. Since the oil is returned to the primary side of the flowmeter, there is a risk that the measured value and the actual amount of oil supplied may not match. In the configurations shown in Figures 2 and 3, the three-way valve V _d cannot be rotated counterclockwise from the position shown in Figure 3 a, nor can it be rotated clockwise beyond the position shown in Figure 3 c. By configuring this as shown in _FIG . Since refueling is performed only in the following manner, there is no possibility of illegal refueling.

In the configuration of FIG. 4, the valves V _a and V _b in FIG. 1 are not used, and instead of the valve V _a , a removable short pipe SP is used, and the return pipe RP is also removable.

When used for normal refueling, attach the short pipe SP and connect the connecting pipe 5 and the oil supply pipe 7-1 of the oil supply device 1.
Connect the next side, remove the return pipe RP, and remove the return pipe RP.
The connecting portion between the connecting pipe 5 and the secondary end portion 7' of the oil feed pipe is sealed with a cap, plug Ca, or the like.

When performing a leakage test, remove cap Ca and install return pipe RP, remove short pipe SP and connect the connection ports with pipes 5 and 7 with cap or stopper Cb.
If the valve is closed in Figure 1, the valve V _a is closed and V _b is open, or the three-way valve in Figure 2 is closed, and the three-way valve is closed in Figure 3 c.
The state is substantially the same as when the switch is switched to the position shown in FIG. If there is no check valve 3 near the oil storage tank 2, an on-off valve Vc may be provided as described above, but instead of such a valve, for example, a structure similar to the short pipe SP shown in Fig. 4 may be used. It is also possible to use the connecting pipe 5 in the vicinity of the tank 2 so that it can be isolated from this tank.

Although the illustrated refueling apparatus is of a ground-mounted type, the method of the present invention can of course be applied to leakage inspections of ceiling-suspended refueling apparatuses, liquid supply apparatuses other than refueling apparatuses, and other devices generally having piping.

As described above, according to the present invention, leakage of piping can be quickly, accurately, and inexpensively inspected using a simple device.

[Brief explanation of drawings]

Fig. 1 is a schematic configuration diagram showing an example of a refueling device that can carry out the method of the present invention, Fig. 2 is a schematic configuration diagram of another refueling device, and Figs. 3 a, b, and c are used in the device shown in Fig. 2. FIG. 4 is a longitudinal cross-sectional view of the three-way valve showing different operating states, and FIG. 4 is a schematic configuration diagram of another oil supply device. 3, 8... Check valve, 5... Communication pipe, 7... Oil feed pipe, 9... Oil supply pump, 13... Air separator, 1
4...Flowmeter, 15...Flow rate pulse transmitter, 19
...Nozzle switch, 20...Control circuit, 21...
...Indicator, RP...Return pipe.

Claims (1)

[Scope of Claims] 1. A pump, a flow meter connected to the secondary side of the pump, a liquid supply pipe connected to the secondary side of the flow meter, and an indicator that displays the amount of liquid measured by the flow meter. a liquid supply device, a liquid storage tank, and one of the pumps;
a communication pipe connecting the liquid storage tank to the next side and having a check valve inserted near the liquid storage tank, the liquid pumped from the liquid storage tank by the pump to the liquid supply pipe; In a liquid supply system in which liquid is supplied through the pump, the steps include: (a) closing or cutting off the communication pipe from the pump near the primary side connection portion of the pump; and (b) supplying the liquid through the pump. (c) operating the pump to increase the secondary side pressure of the pump, and increasing the secondary side pressure of the pump; A method for inspecting leakage in a pipeline, comprising the step of transmitting pressure to the connecting pipeline via the return pipeline. 2. A liquid supply system that includes a pump, a flowmeter connected to the secondary side of the pump, a liquid supply pipe line connected to the secondary side of the flowmeter, and a display that displays the measured liquid volume of the flowmeter. a device, a storage tank, and one of the pumps;
A liquid supply system including a communication pipe connecting the next side and the liquid storage tank, the liquid pumped from the liquid storage tank by the pump being supplied via the liquid supply pipe, (a ) closing or cutting off the communication pipe from the pump in the vicinity of the primary side connection of the pump; (b) connecting the liquid supply pipe to the communication pipe with the storage in the closed or cutoff position; communicating via a return pipe on the liquid tank side; (b') closing or cutting off the communication pipe from the liquid storage tank in the vicinity of the liquid storage tank; and (c) the pump. A method for inspecting leakage in a pipeline, comprising the steps of: increasing the secondary side pressure of the pump; and transmitting this hydraulic pressure to the connecting pipeline via the return pipeline.