JPS606842A - Inspecting method of leak in duct - Google Patents

Abstract

PURPOSE:To inspect a leak in piping easily by connecting a reservoir tank to a pump, flowmeter, and feed liquid pipe by a communication duct through a valve, and installing a duct which returns to the communication duct through a valve. CONSTITUTION:The oil tank 2 buried in the ground is connected to the fed oil pump 8 and flowmeter 14 through the communication pipe 5 having a check valve 3 and a valve Va, and a feed oil is linked atop of a hose 16. The return tube Rp having a valve Vb communicates with the communication tube 5 from an oil transportation tube 7'. When a leak is inspected, the valve Va is closed and the valve Vb is opened; and the pump 9 is driven while the nozzle 17 is detached from a case 18. The pressure in the oil transportation tube 7 rises and is transmitted to the communication pipe 5 through the hose 16 and return tube Rp. When the metered value of the flowmeter 14 is more than the expansion of the hose 16, it is evident that there is a leak in the communication tube 5.

Description

[Detailed description of the invention] The present invention relates to a leakage testing method for 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 wall of a building, there is a risk of leakage. Inspection requires some ingenuity.

Previously, the presence or absence of a leak was determined by sealing both ends of this 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. there were.

In view of the above points, the present invention consists of a pump, a flowmeter connected to the secondary side of the pump, a two-way liquid supply line connected to the secondary side of the flowmeter, and a liquid measuring liquid of the flowmeter. A liquid supply device including a display for displaying the amount, a liquid storage tank, and a primary side of the pump and the liquid storage tank when the liquid is set to mM.
I A series with a back pressure valve installed near the liquid storage tank! δ
A liquid supply system including a waterway, and configured to supply the liquid pumped from the liquid storage tank by the pump through the liquid supply path. closing or cutting off the pump near the primary side connection part of the pump; b) connecting the liquid supply pipe to the connecting pipe t and returning the liquid supply pipe to the liquid storage tank side at the closing or blocking position; C) operating the pump to increase the secondary pressure of the pump;
The present invention proposes a pipe line inspection method that includes a step of transmitting this hydraulic pressure to the communication pipe line via the return line.

If the connecting line does not have a check valve, it is necessary to close or cut off the connecting 'ili' line from the liquid storage tank in the vicinity of the liquid storage tank before carrying out 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 equipment above ground, 2 is the oil storage tank buried underground, 4
5 is a manhole, 5 is a communication pipe (oil suction g) connecting the oil supply device 1 and the tank 2, and 3 is a check valve pushed 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, 11 is a bypass pipe connected to the oil feed pipe γ on the primary and secondary sides of the pump 9, and 12 is an IJ inserted into the bypass all. - an air separator 13 inserted into the oil feed pipe 7 on the secondary side of the pump 9; 14 a flow meter inserted into the oil feed pipe 7 on the secondary side of the air separator 13;
15 is a flow pulse transmitter that generates an electric pulse (flow rate pulse) according to the oil slip measured by the flowmeter 141; 16 is a hose connected to the secondary end of the oil pipe V; The end portion 71 and the hose 16 constitute a liquid supply line.

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. occurs and disappears. Reference numeral 20 indicates a control circuit, and 21 indicates an indicator for the amount of oil supplied, etc., which is returned to zero when the nozzle signal from one nozzle switch disappears when the nozzle 1γ is removed from the nozzle case 18.

The air separator 13 has an air separation chamber 13a and a float chamber 13b.
13c is a communication hole provided in both chambers 13a and 13b, and 13d is a communication hole between the float chamber and the bypass lfg1l 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 vent pipe, and 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, ① is a valve inserted in the connection between the secondary end of the communication pipe 50 and the primary end of the oil feed pipe of the oil supply device 1, and RP is the flow ffl?
A return pipe connecting the secondary side (liquid supply pipe line) of ¥t14 and the communication pipe 5 on the primary side of the valve va, Vb is a valve inserted in the return ffl Rp. R8 also resets the display 21 (
Return 5g) Use the switch to set the nozzle/L'17 to nozzle case 1.
This is for resetting the display 21.

Note that if there is no check valve 3 near the tank 20, another means for closing or cutting off the valve ◯ or the connecting pipe 5 near the tank 20 is required.

When the refueling device 1 is used for normal refueling, valves (a) (and (b)) are opened and valve (b) is closed.

When performing a leakage test, close valve va (and ■.) (step a)) and open valve vb (step b)).

When the claw /l/17 is removed from the nozzle case 718, the motor IQ is energized and the pump 9 is driven.
The pressure inside the oil feed +277 on the next side increases, and this pressure is partially transmitted into the hose 16 and also transmitted to the communication pipe 5 via the return pipe RP (Step 0)).

At this time, the oil in the communication pipe 5 is not returned to the tank 2 due to the check valve 3 (or the closed valve V0).

However, since the hose 16 is elastic and expands, the flowmeter 14 measures the amount of oil corresponding to the expansion of the hose, and the measured value is displayed on the display 21.However, if there is no melt from the connecting pipe 5, more oil 11 amounts are not performed. Therefore, when the measured value for the known hose expansion is displayed, by pressing the reset switch R3 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.

In addition, if switch R8 is not provided, in order to reset the display for the hose expansion, temporarily close the nozzle 17 to the nozzle case 718.
You may reset the display 21 to zero, remove the nozzle p from the nozzle case again, and restart the pump 9. 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 jug 22 before or during the inspection.

FIG. 2 shows another depiction 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, valves V8 and Vb in Fig. 1 are one three-way valve vd and 11? It has been replaced. This three-way valve Vd forms a groove connecting the communication pipe 5, the oil supply pipe 7 in the oil supply device 1, and the return pipe RP, and an example of a concrete construction of 47η is shown in Fig. Shown below.

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 three-way valve ■d
The spherical valve body 31 is in the position shown in FIG.
is closed to the pump primary side of the oil feed pipe 7 and the connections n and F 5 t.

When performing a leakage test, rotate the spherical valve body 31 clockwise from position n in Figure 3(a) to
When stopped at the position shown in Figure (c), the return pipe RP is connected to the valve body 31.
It communicates with the communication pipe 5 through the large-diameter through-flow path 32 and the small-diameter cloudy flow path 33, but is blocked from the primary side of the pump of the oil supply system 7.

In the case of Fig. 1, if valve vb is left open intentionally or carelessly for fraudulent purposes under normal conditions, once i
t hl Some of the oil was returned without being refueled 11? Rp
Since the fuel is returned to the primary side for flow rate via the flow rate, there is a risk of fraud in which the measured value and the actual oil supply J:'C do not match. According to the 116th commandment in Figures 2 and 3 (\), the three-way valve Vd cannot be rotated counterclockwise from position i'+1 in Figure 3 (a), and the three-way valve Vd in Figure 3 (C) cannot be rotated counterclockwise. 1. Therefore, no matter which rotational position of the three-way valve Vd is in place, the connection pipe 5, the oil feed ff7, and the return pipe RP cannot be rotated in the clockwise direction. are not communicated at the same time, and the third
Since refueling is performed only at the 1st position in Figure (a), there is no possibility of unauthorized refueling.

In the configuration t7y in FIG. 4, the valves 8 and Vb in FIG. 1 are not used, and a removable short pipe SP is used in place of the valve 4, and the return pipe RP is also removable.

When used for normal refueling, install the smoke pipe SP and connect the communication pipe 5 and the primary side of the oil feed pipe 70 of the refueling device 1,
The return rib RP is removed and the connection portion between the return member 9RP and the connection m W 5 and the secondary end portion 71 of the oil feed pipe is sealed 17 with a cap, plug Oa, or the like.

When performing a leakage test, remove and return the cap Oa, attach IIT; RP, remove the short pipe SP, and close the connection port with the pipe 5.7 with a gap or plug cb. The state in which Va is closed and Vb is opened, or the state in which the three-way valve in FIG.
If there is no check valve 3 near 0, an open rJJ valve Vc may be provided as described above, but instead of such a valve, for example, a structure similar to the short pipe SP in Fig. 4 may be used for communication. It is also possible to provide that the pipe 5 can be shut off from the tank 20 close to this tank.

Although the illustrated refueling system is of the above-ground membrane "L type," it goes without saying that the method of the present invention can be applied to leakage inspections of ceiling-suspended refueling systems, liquid supply systems other than refueling systems, and other equipment with general e-piping. It is.

As described above, according to the present invention, it is possible to quickly, accurately and safely inspect piping for leakage using a simple device.

[Brief explanation of the drawing]

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 Fig. 3(a) (13(c) is a A vertical sectional view of a three-way valve used in the device showing different operating states, and FIG. 4 is a schematic 17G diagram of another oil supply device. 3.8...Check valve, 5. ...Connection pipe, 7...Oil pipe, 9...Oil supply bonder, 13...Air separator, 1
4... Flow rate bar 1.15... Flow rate pulse transmitter, 19... Non-null switch, 20... Control circuit, 21... Display, I(P・
...Return pipe. 2I21 Figure 3(b) (C)

Claims (2)

[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 a display for displaying the measured liquid amount of the flow meter. A liquid supply device;
a liquid storage tank; and a communication pipe line having a 1g:CI between the primary side of the pump and the liquid storage tank and a check valve inserted near the liquid storage tank, In a liquid supply system in which liquid pumped from a tank is supplied via the liquid supply pipe, a) the connecting pipe is closed to the pump t near the primary side connection part of the pump, or 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; and C) operating the pump to Increase the secondary side pressure of
A method for inspecting leakage in a pipe line, comprising the step of transmitting this liquid pressure to the communication pipe line via the return pipe line. (2) A pump, a liquid supply pipe connected to the secondary side of the pump, a liquid supply pipe connected to the secondary side of the flowmeter, and an indicator that displays the m-side flow rate of the flowmeter. a liquid supply device having a temperature of 0;4, a liquid storage tank, and a communication pipe connecting the primary side of the pump and the liquid storage tank, the liquid pumped from the liquid storage tank by the pump to the supply liquid? In a liquid supply system adapted to supply liquid via a pipe, the steps include: a) closing or blocking the connecting pipe to the pump in the vicinity of the downstream connection of the pump, and b) communicating the liquid supply pipe with the 71p connecting pipe via a return pipe on the side of the liquid storage tank at the closed or cutoff position; a step of closing or shutting off the liquid storage tank 1; and C) a step of operating the pump to increase the secondary side pressure of the pump and transmitting this liquid pressure to the connecting pipe via the return pipe. A method for inspecting leakage of pipes, characterized in that: