JP6912617B1 - Jig for inspection of water spray equipment for tunnels - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily inspect even a place where a water collector of a water spray equipment inspection vehicle cannot be used, such as a pit interval of a water spray head or various obstacles in a tunnel, and without taking up space. Inspection of water spray equipment for tunnels, where parts can be installed, the hose can be connected in a stable state without the hose itself turning when using the hose, and water stoppage is perfect as a measure against water leakage. Provide a jig for use. SOLUTION: A clamper 8 is formed by a ring having a grooved projection piece for locking on the outer periphery to be attached to a water spray nozzle side, and a catch hooked on the side portion with a grooved projection piece 9 for locking the clamper. A clip 17 is attached, and one end of the clamper 8 is in contact with the clamper 8 to form a cylindrical coupling joint 16 that accommodates a water outlet of a water spray nozzle inside. [Selection diagram] Fig. 1

Description

The present invention relates to an inspection jig for a water spray facility for a tunnel.

Tunnels such as highways are equipped with water spray equipment to deal with fires.

The water spray equipment includes a water spray nozzle arranged at a predetermined interval (for example, every 5 m) at the upper part in the axial direction of the tunnel, a valve device for controlling the supply of water to the water spray nozzle, and a pump for pumping water. Equipped with a device.

The water spray nozzle is formed by fixing the nozzle head to the tip of a branch pipe connected to a water distribution pipe extending in the axial direction of the tunnel, and is uniformly sprayed into the tunnel according to the shape and dimensions of the tunnel. As described above, various nozzle heads such as a long-distance casting head and a short-casting head are provided, an arbitrary number of nozzle heads are provided, and the water discharge direction of the nozzle heads is adjusted.

When a fire is detected in the tunnel, the pump device is activated by remote operation or automatic control, the valve device is opened and operated to supply water to the water spray nozzle, and atomized water is discharged from the water spray nozzle. Fill the tunnel with mist of water. As a result, the cooling effect due to the evaporation of water and the oxygen deficiency effect due to the filling of water droplets are exhibited to suppress fire and protect the tunnel.

It is necessary to check the water discharge performance of such a water spray device in a tunnel at a certain frequency (about once every two years) and check for clogging of the water spray nozzle due to deformation, rust, or the like.

In the conventional inspection of clogging of the water spray nozzle, the traffic in the tunnel is completely blocked and water is actually sprayed from the water spray nozzle, and the clogging of the water spray nozzle is individually checked by the operator's visual inspection or manual weighing. However, this inspection method has a large impact on traffic because the road is completely closed.

Therefore, as described in the following patent documents, conventionally, an inspection vehicle for a water spraying facility equipped with a container that receives water from a water spray nozzle and an electromagnetic flow meter that measures the flow rate of the water received by the container has been proposed. ..
Japanese Patent No. 4002674

As shown in FIGS. 21 and 22, the inspection vehicle 1 of this water spraying facility is provided with a workbench bucket 3 that can be raised and lowered via a lifter 2 for raising and lowering, and the workbench bucket 3 is provided with various devices in addition to various devices. The longitudinal arm 4 of the tunnel is provided to be telescopic, rotatable around the vertical axis, and horizontally movable in one direction, and the arm 4 is provided with 3 to 3 water collectors 5 as containers that individually surround the water spray nozzles. Five pieces are provided so that they can slide sideways and move back and forth.

As shown in FIG. 23, the water spray nozzle installed in the tunnel is surrounded by the water collector 5 whose position can be adjusted up and down, left and right, and front and back, and the spray amount can be measured without scattering the water spray around.

This function enables inspections under lane restrictions and avoids complete road closures in tunnels.

In addition, the amount of spray is measured in real time by an electromagnetic flow meter, transmitted from the slave unit to the master unit by SS radio (specific low power type radio), and the measurement result is recorded on the personal computer in the vehicle cabin where the master unit is installed. Will be done. Air is removed from the water received by the container with a gas-liquid separation tank, the flow rate is measured with an electromagnetic flow meter, and then the air is discharged to a drainage ditch on the road.

The following patent documents have been proposed as the use of a special vehicle is not essential and the cost of the vehicle used for inspection can be effectively reduced.
Japanese Patent No. 5166361

As shown in FIGS. 24 and 25, the patent document 2 is a water spray nozzle used in a water spray facility for a tunnel, and a nozzle head that discharges atomized water and the nozzle head. Also exposed on the wall surface side of the tunnel, connected to the attachment of the inspection device of the water spray equipment for the tunnel, and the attachment connecting part that accommodates the nozzle head and forms a sealed water collection chamber together with the attachment. Be prepared.

The water spray nozzle 11 is installed at the upper part of the tunnel 7 and is arranged on the water distribution pipe 12 extending in the axial direction of the tunnel at predetermined intervals in the axial direction of the tunnel. An attachment 32 connected to the nozzle 11, a gas-liquid separation device, a flow meter, and a drainage device are sequentially configured.

The attachment 32 has a stainless steel box-shaped body 21 having an opening on one surface, and a urethane packing 24 as a sealing member is provided around the opening 21a of the box-shaped body 21.

Two operating portions 36 for snap locks are provided on both side surfaces, the top surface, and the opening 21a side of the bottom surface of the box-shaped body 21, and two couplings 23 are provided on the bottom surface of the box-shaped body 21 at the lower end. The discharge pipe 22 provided with the above is fixed.

To attach the attachment 32 to the water spray nozzle 11, the nozzle head 14 and the tip of the branch pipe 13 are housed inside through the opening 21a of the attachment 32, and the packing 24 of the attachment 32 is brought into close contact with the edge of the connecting plate 15. In this state, the operation portion 36 of the snap lock of the connecting plate 15 is operated to connect the attachment 32.

By manual operation, the pump device of the water spray facility is started and the valve device is opened and operated to start pumping water to the water distribution pipe 12. When water is pumped to the water distribution pipe 12, water is supplied to each water spray nozzle 11 through the branch pipe 13, and water is discharged from the nozzle head 14 of the water spray nozzle 11. The water discharged from the nozzle head 14 is collected without leakage in the water collecting chamber formed by the attachment 32 and the connecting plate 15, and sent to the gas-liquid separator through the discharge pipe 22 and the hose of the attachment 32, and is sent by the flow meter. The flow rate is measured.

In the case of the water spray equipment inspection vehicle, it is necessary to continue to support the water collector while accommodating the water spray nozzle while discharging the water from the water spray nozzle. Must be held in position.

If the location where the water spray nozzle is installed is a narrow space or there is a blower or other obstacle in the vicinity, the water spray nozzle installed in the tunnel cannot be surrounded by the water collector, making it unusable.

In Patent Document 2, the attachment is made of a stainless steel box-like body having an opening on one surface, and has an attachment connecting portion that accommodates two nozzle heads and forms a sealed water collecting chamber together with the attachment. In preparation for forming a catchment chamber, it becomes large as a whole and takes up a lot of space.

Further, regarding water stoppage, since the space between the box-shaped body and the attachment connecting portion is sealed with a sealing member, it is said that leakage of water discharged from the water spray nozzle from the water collecting chamber can be effectively prevented. However, it is difficult to expect effective water stoppage only with such snap locks and sealing members.

An object of the present invention is to solve the above-mentioned inconvenience of the conventional example, and to easily inspect even in a place where the water collector of the water spraying equipment inspection vehicle cannot be used, such as the pit spacing of the water spraying head and various obstacles in the tunnel. In addition, parts can be installed without taking up space, the hose itself can be connected in a stable state without turning when using the hose, and water stoppage as a measure against water leakage is also possible. The purpose is to provide a perfect inspection jig for tunnel water spraying equipment.

In order to achieve the above object, the present invention according to claim 1 has a clamper formed by a ring having a grooved protrusion for locking on the outer periphery thereof to be attached to the water spray nozzle side, and the clamper is locked on the side portion. The gist is that a catch clip that hooks on a grooved protrusion is attached, and one end of the clamp comes into contact with the clamper to form a cylindrical coupling joint that houses the water outlet of a water spray nozzle inside.

According to the first aspect of the present invention, the jig comprises a clamper with a ring and a cylindrical coupling joint in which one end abuts on the clamper to accommodate the water outlet of the water spray nozzle. Since it can be attached to each of the outlets, it does not take up space, and the water discharged from each outlet can be sent to the flow meter without leaking by connecting a hose, and a water spray facility for tunnels. Can be inspected.

Further, since the cylindrical coupling joint is fixed to the clamper by the catch clip, if there are catch clips on the left and right, there is no possibility that the hose will rotate as in the case of using the cam lock type joint or the Machino type joint.

The gist of the present invention according to claim 2 is that the cylindrical coupling joint has an engaging screw formed on the outer circumference or the inner circumference of the end opposite to the end abutting the clamper.

According to the second aspect of the present invention, even when a water pipe or the like is connected to a cylindrical coupling joint, it is easily connected by an engaging screw provided on the outer or inner circumference of the end opposite to the end that contacts the clamper. can do.

According to the third aspect of the present invention, the recess provided in the clamper and the inner space of the end portion of the cylindrical coupling joint that abuts on the clamper form a recess for accommodating the overhanging portion of the water spray nozzle. A seal packing by an O-ring is arranged in the inner space of the end of the cylindrical coupling joint that abuts on the clamper, and this is pressed near the water discharge port of the water spray nozzle to allow water from the water discharge port to reach the clamper. The gist is to stop the water so that it does not go.

According to the third aspect of the present invention, a seal packing with an O-ring is arranged and pressed near the water discharge port of the water spray nozzle to stop the water from the water discharge port from going to the clamper. Therefore, the connection between the cylindrical coupling joint and the clamper is only pressure welding with a catch clip, and there is no need to pay special attention to water leakage.

The gist of the present invention according to claim 4 is that an inward flange is formed at the bottom portion of a recess provided in the clamper.

In the present invention according to claim 4, the inward flange is useful for fixing the clamper, and by sandwiching the clamper with a hexagon nut or the like, the clamper can be fixed near the water discharge port of the water spray nozzle.

As described above, the inspection jig for the tunnel water spraying equipment of the present invention can be easily inspected even when the water spraying equipment inspection vehicle cannot be used, and there are narrow spaces or obstacles in the surrounding area. It can be installed without removing it, the hose can be connected stably without turning even when using a hose, and the water stoppage as a measure against water leakage is perfect.

It is a side view of the use state which shows 1 Embodiment of the inspection jig of the water spray equipment for a tunnel of this invention. It is a perspective view which shows one Embodiment of the inspection jig of the water spray equipment for a tunnel of this invention. It is the whole view of the tunnel at the time of inspection of the water spray equipment for a tunnel using this invention. It is a side view which shows an example of the water spray equipment for a tunnel. It is a vertical sectional side view of a main part which shows an example of the water spray equipment for a tunnel. It is a front view of the main part which shows an example of the water spray equipment for a tunnel. It is a side view of the state before the catch clip of the cylindrical coupling joint which shows 1st Embodiment of the inspection jig of the water spray equipment for a tunnel of this invention can be removed. It is a longitudinal side view of the state before the catch clip of the cylindrical coupling joint which shows 1st Embodiment of the inspection jig of the water spray equipment for a tunnel of this invention can be removed. It is a top view of the state before the catch clip of the cylindrical coupling joint which shows 1st Embodiment of the inspection jig of the water spray equipment for a tunnel of this invention can be removed. It is a bottom view of the state before the catch clip of the cylindrical coupling joint which shows 1st Embodiment of the inspection jig of the water spray equipment for a tunnel of this invention can be removed. It is a perspective view of the clamper which shows 1st Embodiment of the inspection jig of the water spray equipment for a tunnel of this invention. It is a top view of the clamper which shows 1st Embodiment of the inspection jig of the water spray equipment for a tunnel of this invention. It is a longitudinal side view of the clamper which shows 1st Embodiment of the inspection jig of the water spray equipment for a tunnel of this invention. It is a side view of the state before removing the catch clip of the cylindrical coupling joint which shows the 2nd Embodiment of the inspection jig of the water spray equipment for a tunnel of this invention. It is a longitudinal side view of the state before the catch clip of the cylindrical coupling joint which shows the 2nd Embodiment of the inspection jig of the water spray equipment for a tunnel of this invention can be removed. It is a top view of the state before removing the catch clip of the cylindrical coupling joint which shows the 2nd Embodiment of the inspection jig of the water spray equipment for a tunnel of this invention. It is a bottom view of the state before removing the catch clip of the cylindrical coupling joint which shows the 2nd Embodiment of the inspection jig of the water spray equipment for a tunnel of this invention. It is a perspective view of the clamper which shows the 2nd Embodiment of the inspection jig of the water spray equipment for a tunnel of this invention. It is a top view of the clamper which shows 1st Embodiment of the inspection jig of the water spray equipment for a tunnel of this invention. It is a longitudinal side view of the clamper which shows 1st Embodiment of the inspection jig of the water spray equipment for a tunnel of this invention. It is a side view of the inspection vehicle of a water spray facility. It is a rear view of the inspection vehicle of a water spray facility. It is a perspective view of the inspection vehicle of a water spray facility. It is a perspective view which shows the attachment of the inspection device of the water spray equipment for a tunnel in the conventional example. It is a perspective view which shows the water spray nozzle which inspects the water discharge by the inspection device of the water spray equipment for a tunnel in the conventional example.

Hereinafter, embodiments of the present invention will be described in detail with respect to the drawings. FIG. 1 is a side view of a usage state showing one embodiment of the inspection jig for the tunnel water spraying equipment of the present invention, and FIG. 2 is a perspective view showing one embodiment of the inspection jig for the tunnel water spraying equipment of the present invention. The jig of the present invention has a clamper 8 made of a ring having a protrusion 9 with a locking groove 10 formed on the outer periphery thereof to be attached to the water spray nozzle side, and a locking groove 10 of the clamper 8 on the side surface. A catch clip 17 that hooks on the projecting piece is attached, and one end thereof abuts on the clamper 8 to form a cylindrical coupling joint 16 that houses the water outlet of the water spray nozzle inside.

First, the water spraying equipment for a tunnel to which the jig of the present invention is attached will be described. As shown in FIGS. 4 to 6, for example, one automatic valve device is installed in each water discharge section at intervals of 25 meters, and stands up from the automatic valve device. The water spray nozzle 11 is connected to the tip of the head pipe to which the branch pipe 13, the elbow joint, and the pipe are connected, which is raised and lowered from the water distribution pipe 12 arranged along the upper wall surface of the tunnel.

When the fire detector detects that a fire has occurred in the tunnel, the fire detector sends a fire signal to the control device to start the pump, and the pressurized water stored in the water tank is pumped through the water supply pipe. Then, the automatic valve device installed in the fire area is operated to supply pressurized water to a plurality of water spray nozzles and discharge the water all at once.

The water spray nozzle 11 is divided into a long-distance discharge port 18 and a near-cast water discharge port 19 by a body 20 in a direction of about 90 degrees, and the long-distance water discharge port 18 is attached with a deflector 37 by a presser nut 25.

The near-throw water discharge port 19 is composed of an internal nozzle 38 and an external nozzle 39, and forms a spiral 40 inside.

In the figure, reference numeral 30 denotes a plastic dustproof cap that covers the long-distance discharge port 18 and the near-cast water discharge port 19.

Both the clamper 8 and the cylindrical coupling joint 16 are made of stainless steel and are heavy and robust. The clamper 8 will be described first. As shown in FIGS. 11 to 13 and 18 to 20, it has a disk shape. The ring forms a circular recess 26 (Φ41.5, 42) that opens on the upper surface around the penetrating portion.

Further, the clamper 8 is formed by integrally forming a donut ring-shaped inward flange 6 at the bottom portion of the circular recess 26.

The flange 6 can be used for fixing the clamper 8, and by sandwiching the flanger 8 with a hexagon nut or the like, the clamper 8 can be fixed near the water discharge port of the water spray nozzle.

The projecting piece 9 with the locking groove 10 is rectangular, and the number thereof is determined according to the number of catch clips 17 described later, and the locking groove 10 is downward so as to cross the rectangular projecting piece 9 in the width direction. Open.

Although not shown, the clamper 8 is provided with a rectangular projecting piece at a symmetrical position in addition to the projecting piece 9 with a locking groove 10, the entire projecting piece is divided into half, and the projecting piece is screwed. It is possible to tighten and tighten as a so-called choker type that stops with.

The cylindrical coupling joint 16 is a coupling in the sense that the long-distance discharge port 18 and the near-cast water discharge port 19 of the water spray nozzle 11 are housed inside, but there are two catch clips 17 provided on the outer side thereof. Is attached. A catch clip is a metal fitting that is also called a "patch lock" or "buckle", and the lever hook is pulled and fixed by the force of a spring. The catch clip 17 is preferably equipped with a lock 17a.

As shown in FIGS. 7 to 10 and 14 to 16, the outer circumference of the cylindrical coupling joint 16 has a reduced diameter in the upper half, and reaches the end opposite to the end 28 in contact with the clamper 8. A joint screw 27 was formed. The engaging screw 27 may be formed on the inner peripheral side instead of the outer peripheral side.

The inside of the cylindrical coupling joint 16 is a thick portion protruding inward, and is divided into an upper vacant space 29 and a lower vacant space 30, and the upper vacant space 29 is a water discharge port 18 of the water spray nozzle 11 or a near space. It serves as a housing for the water outlet 19.

Further, the lower vacant space 30, which is a vacant space inside the end portion 28 that abuts on the clamper 8, has the same diameter as the circular recess 26 of the clamper 8, and is combined with the circular recess 26 to form an overhanging portion of the spray nozzle (FIG. 5. In FIG. 6, a recess for accommodating the portion b (for example, a hexagon nut) is formed.

In the figure, 31 is a concave groove, and although not shown, a seal packing by an O-ring is arranged here. In the case of the cylindrical coupling joint 16 shown in FIGS. 7 to 10, the concave groove 31 is formed on the inner peripheral surface of the thick portion divided into the upper space 29 and the lower space 30, and is shown in FIGS. 18 to 20. In the case of the cylindrical coupling joint 16, it was formed on the lower surface of the thick portion.

The hole penetrating the side wall of the cylindrical coupling joint 16 is a screw insertion hole for attaching the catch clip 17.

Next, the usage will be described. The clamper 8 and the cylindrical coupling joint 16 of the present invention are attached to the long-distance discharge port 18 and the near-cast water discharge port 19 of the water spray nozzle 11, respectively, and the cylindrical coupling joint 16 shown in FIGS. 7 to 10 The clamper 8 shown in FIGS. 11 to 13 is attached to the water discharge port 19 for near casting, and the cylindrical coupling joint 16 shown in FIGS. 18 to 20 and the clamper 8 shown in FIGS. 18 to 20 are attached to the water discharge port 18 for long casting. It is to be attached.

First, the clamper 8 is attached to the water spray nozzle 11 side. FIG. 5a corresponds to the portion where the clamper 8 fits, and the root portion of the long-distance discharge outlet 18 corresponds to this.

The clamper 8 may be fixedly installed on the water spray nozzle 11 at all times.

An overhanging portion of the spray nozzle (part b in FIGS. 5 and 6 such as a hexagon nut) is placed in a recess formed by bringing the end 28 into contact with the clamper 8 and combining the lower space 30 and the circular recess 26. The water discharge port 18 for long-distance casting and the water discharge port 19 for short-distance casting are housed in the upper space 29 of the cylindrical coupling joint 16, and the clamper 8 and the cylindrical coupling joint 16 are fixed by the catch clip 17.

The catch clip 17 hooks the lever hook into the locking groove 10 of the projecting piece 9 of the clamper 8 and rotates the handle of the operating portion to pull the engaging portion and hold it in the towed state.

In this case, the seal packing by the O-ring arranged in the concave groove 31 is pressed against the water discharge port of the water spray nozzle, specifically, the portion c (hexagon nut or the like) shown in FIGS. 5 and 6. The water discharge port 18 for long-distance casting and the water discharge port 19 for short-distance casting are stopped so as not to go to the clamper 8.

A hose 35 provided with a Machino-type joint 34 is connected to the cylindrical coupling joint 16 via an engaging screw 27 via a joint hardware 33, and this hose 35 is, for example, a gas-liquid separator provided in an inspection vehicle 1 of a water spray facility. Lead to a flow meter.

The Machino type joint 34 is a joint specified in Japanese Industrial Standards JISB 9911, and is composed of male and female metal fittings that fit in the axial direction. The male and female metal fittings can be connected and disconnected with a single touch. There is.

Specifically, at the time of connection, the claw member provided inside the female metal fitting and urged inward in the circumferential direction engages with the annular protrusion provided at the tip of the male metal fitting to connect the male metal fitting and the female metal fitting. The state is retained. On the other hand, when the connection is released, when the annular push ring provided on the hose side of the male metal fitting is slid toward the female metal fitting, the tip of the push ring comes into contact with the inclined surface of the claw member in the female metal fitting, and the claw member Evicted outward in the radial direction.

As a result, the engagement between the claw member of the female metal fitting and the protrusion of the male metal fitting is released, and the connection between the male metal fitting and the female metal fitting is released.

In this way, the connection can be made by inserting the tip of the male metal fitting into the inside of the female metal fitting, and the connection can be released by sliding the push ring of the male metal fitting toward the female metal fitting.

The hose 35 is preferably a transparent crystal hose whose inside is visible.

The destination to which the hose 35 leads is a device in which these gas-liquid separation devices, flow meters, and drainage devices are installed on a trolley, etc., in addition to the gas-liquid separation device and flow meter provided in the inspection vehicle 1 of the water spray equipment as described above. It may be.

When the jig of the present invention has been attached to all the water spray nozzles 11 to be inspected, the pump device of the water spray facility is started and the valve device is opened and operated by manual operation to pump water to the water distribution pipe 12. To start.

When water is pumped to the water distribution pipe 12, water is supplied to each water spray nozzle 11 through the branch pipe 13, and water is discharged from the long-distance spray discharge port 18 and the near-spray water discharge port 19 of the water spray nozzle 11. ..

The water discharged from the long-distance discharge port 18 and the short-distance discharge port 19 is removed by separating air with a gas-liquid separator through a cylindrical coupling joint 16, a joint hardware 33, a Machino type joint 34, and a hose 35. , The flow rate is measured with a flow meter.

When the measurement of the water discharge flow rate of the water spray nozzle 11 is completed, the pump device of the water spray facility is stopped and the valve device is closed to stop the pumping of water to the water distribution pipe 12.

As a result, the discharge of water from the water spray nozzle 11 is stopped. When the water discharge of the water spray nozzle 11 is stopped, the cylindrical coupling joint 16 is removed from the water discharge port 18 for long-distance casting and the water discharge port 19 for near-casting of the water spray nozzle 11.

1 ... Inspection vehicle for water spray equipment 2 ... Lifter for raising and lowering 3 ... Worktable bucket 4 ... Arm 5 ... Water collector 6 ... Flange 7 ... Tunnel 8 ... Clamper 9 ... Projection 10 ... Locking groove 11 ... Water spray Nozzle 12 ... Water distribution pipe 13 ... Branch pipe 14 ... Nozzle head 15 ... Connecting plate 16 ... Cylindrical coupling joint 17 ... Catch clip 17a ... Lock 18 ... Long-distance water discharge port 19 ... Near-cast water discharge port 20 ... Body 21 ... Stainless steel Box-shaped body 21a ... Opening 22 ... Discharge pipe 23 ... Coupling 24 ... Packing 25 ... Presser nut 26 ... Circular recess 27 ... Engagement screw 28 ... End 29 ... Upper vacant space 30 ... Lower vacant space 31 ... Recessed groove 32 ... Attachment 33 ... Fitting hardware 34 ... Machino type fitting 35 ... Hose 36 ... Operation unit 37 ... Deflector 38 ... Internal nozzle 39 ... External nozzle 40 ... Spiral

Claims (4)

A clamper with a ring having a grooved protrusion for locking on the outer circumference to be attached to the water spray nozzle side and a catch clip for hooking on the grooved protrusion for locking of the clamper are attached to the side portion, and one end is attached. A jig for inspecting water spray equipment for tunnels, which comprises a cylindrical coupling joint that comes into contact with the clamper and accommodates a water discharge port of a water spray nozzle inside. The jig for inspecting a water spray facility for a tunnel according to claim 1, wherein the cylindrical coupling joint has an engaging screw formed on the outer circumference or the inner circumference of the end opposite to the end abutting the clamper. A recess provided in the clamper and a vacant space inside the end of the cylindrical coupling joint that abuts the clamper form a recess for accommodating the overhanging portion of the water spray nozzle, and the cylindrical coupling joint is said to have a recess. A seal packing by an O-ring is arranged in the inner space of the end portion that comes into contact with the clamper, and this is pressed near the water discharge port of the water spray nozzle to stop water from the water discharge port so that it does not go to the clamper. The jig for inspecting the water spray equipment for a tunnel according to claim 1 or 2. The jig for inspecting a water spray facility for a tunnel according to any one of claims 1 to 3, wherein an inward flange is formed at the bottom of a recess provided in the clamper.

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