JPS58103472A - Apparatus for forming water curtain - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device for forming a water curtain for blocking leakage gas or flames, and is particularly effective for blocking leakage gas of liquefied petroleum gas (LPG) and diffusing and diluting it. The present invention relates to a water curtain forming device that is easy to carry.

In the event that LPG leaks locally due to an accident, it is important for safety to quickly shut off the leak and diffuse and dilute the LPG Q to below the explosion limit. For this reason, the leakage point is surrounded on all four sides with a water curtain. LP
It is known that when G leaks near the ground, if it is guided to a height of more than 5 degrees above ground, the LPG will be diffused and diluted to a degree below the explosive limit due to the difference in temperature with the air. Therefore, it is desirable that the height of the water curtain is sfI& or more.

For fixed LPG tanks, [i515m:
However, for moving equipment such as tank trucks and railway tank cars, or for plants where leakage may occur over a wide area, a portable water curtain can be installed. Portable water spring forming devices are usually supplied with water via fire hoses from fire trucks or fire hydrants. 65 A (2% B) is standard, and the water supply pressure at the hose end is less than 10 Kt/d, usually in the range of 2 to 3 cti to 6 to 8 o'clock/-.Therefore, the water curtain forming device 1rFi It must be possible to obtain the desired water curtain with water pressure and water volume within this range.

It has been known to use a water cannon with a spray nozzle attached as a water curtain forming device. Such a water curtain forming device is convenient to carry, but since the water curtain is cup-shaped rather than vertical, it is difficult to stabilize a water curtain of a light height that would cost $7'j above. It is difficult to form As another example of water curtain formation and installation, a fixed or portable device in which a plurality of water spray nozzles are arranged in parallel or radially has been proposed.

(%1 Publication No. 54-158100) However, even if such a device is portable, it is not very convenient to carry because it uses a plurality of nozzles, and also requires a large amount of water.

Attach a patch plate to the tip of the water discharge pipe, form a #1 semi-circular spout upward at the tip, and eject water from this semi-circular spout, and the ejected water will be #1. It spreads radially vertically and forms a nearly fan-shaped water curtain. However, as the injected hot water spreads radially, its thickness and velocity rapidly decrease, resulting in numerous radial cuts at the outer edge of the fan-shaped water curtain. Since the occurrence of such breaks reduces the effective area of the water curtain, it is desirable to prevent this occurrence as much as possible.

The present invention suppresses the occurrence of cuts as described above.

To provide a water curtain forming device capable of forming a fan-shaped water curtain having the most effective shape and spread for a given water spouting speed 1L and flow rate.

That is, in the present invention Vi, an upward semicircular ejection hole is formed and provided at the tip of the water discharge pipe that contacts the backing plate.

In the water curtain forming device of the present invention, the thin water streams arranged along the semicircular jet holes and ejected from the plurality of auxiliary waterways replenish the water amount to the outer edge of the M-shaped water curtain and merge with the water curtain. death,
Thus, it is possible to maintain a solid and stable water curtain with no breaks in the entire radius.

The plurality of auxiliary water channels arranged along the semicircular jet hole may be independent from the jet port.

Preferably, one end thereof is a groove communicating with the spout and extending in the axial direction of the water discharge pipe. Multiple ll11 with different lengths
It is more preferable that #ll be arranged alternately. Water streams spouted from auxiliary channels of different lengths.

This is because the water curtains are combined with the water curtains at different positions in the nine radial directions, which is more effective in preventing the cuts.

It is effective to provide as many auxiliary water channels as possible for reinforcing the water curtain, and it is desirable to provide them at intervals of KIO@ or less on the circumference of the semicircular jet hole.

The area of the spout is determined to obtain a jet velocity sufficient to maintain the desired water curtain height. The ejection velocity is at least about 1
It is essential that it be 0 inertia/#-〇.

In addition, in order to ensure the strength of the water curtain, it is necessary to give the water curtain a light thickness.In this case, K is the opening width in the longitudinal direction of the semicircular jet hole, and the jetting speed f is excessively reduced. It is effective to maintain the ejection flow rate at least 18 to 20 g1/hrK by increasing the amount as much as possible within the range that does not cause this.

When using the water curtain forming device i1M of the present invention, it is installed on a low support stand close to the ground <Km<, and the device is strongly pressed against the ground by the reaction force of the upward jet of water. This prevents the device from moving longitudinally due to the reaction force when water impinges on the caul plate, and thus allows the device to be fixed in place without the need for human intervention.

The device of the present invention can be connected to an existing fire hydrant or fire engine with a hose, and these can be used as a water supply source at any location with a width of approximately 15 f.
A water curtain can be formed covering I & more. By surrounding the leak point using the devices of the present invention + 14 units,
It is possible to prevent leakage from spreading to other locations.

Since the device of the present invention is easy to operate, it can quickly form a water curtain and perform its protective function after installation.

The device of the present invention is lightweight and can be carried and operated by one person. Also, since no special spray nozzle is used, manufacturing and maintenance costs are low.

The water curtain forming device of the present invention is particularly useful for diffusive dilution of LPG leaking from tank lorries, railway tank cars, or piping inside plants. In addition, since the water curtain has a radiant heat shielding effect, it can be effectively used to prevent burns in general fires and oil fires.

Next, a specific example of the water curtain forming device of the present invention will be explained with reference to the drawings.

In FIGS. 1 and 2, it is connected to a water supply source via a hose (not shown) attached to a water discharge pipe + 11Fi hose coupling (2). The upper half of the tip of the water discharge pipe is shallowly notched to form a notched end face (4) parallel to the end face (3) of the pipe. A plurality of long vertical grooves (5), . . . and short vertical grooves (6), . . . extending axially from the notch end surface (4) are alternately formed. . A relief plate (7) is attached to the end face (3) of the tube, even by Fi welding, and the plate (7), the notched end face (4), and K form an upward semicircular jet nozzle ( 8) is formed.

Water cannon! (1) is supported on the support stand (1) through the legs i91 f: the support stand (11) has four radial arms (12)
installed on top.

Examples of dimensions of the main wall portion of the above device are as follows. The inner diameter of the water discharge pipe is 68mm, the width of the semicircular spout (8) is sm,
Long vertical groove (5) length 5■, short vertical groove (6) length 2
5-1 The width of the vertical groove is 1.5 am, the vertical groove has a 5″ gap, and a total of 37
There are several. The backing plate (7) is 1!80aam horizontally,
At a height of 1301 m, the center of the backing plate (7) and the center of the pipe f11 almost coincide.

To form a water curtain, when the device w shown in Figure 1 is connected to a water supply source, such as a fire hydrant, the water that has entered the water discharge pipe (1) will still collide with the plate ()), and the semicircular spout (8) and It radiates almost vertically upward through the longitudinal grooves (5), (6), thus forming a continuous fan-shaped stable water curtain.

3 to 5 show other examples of auxiliary water channels.

In the example shown in FIG. 3, one end of the auxiliary water channel is connected to the jet hole (8) and consists of a vertical groove of equal length. The shape of the groove can be the rectangular Sendai shape shown in the figure, a threaded shape, a round shape, or a combination thereof.

FIGS. 4 and 5 are examples in which the auxiliary water channels are formed independently of and arranged in the vicinity of the circumferential spout (8),
Figure 4 shows an example in which the auxiliary channels (5)' are lined up along the spout (8), and Figure 5 shows the auxiliary channels (5)' and (6).
This is an example in which the bits are arranged in a staggered manner. The shape of the hole may be rectangular.

Further, the auxiliary water channel may be a combination of a formal water channel connected to the spout and an independent water channel.

EXAMPLE A friend who conducts a water curtain forming experiment using the water curtain forming device Wt having the same shape as shown in FIG. 1. release'! The inner diameter of +11 is 68cm, and the cross-sectional area is 361h♂.

Also, the width of the circumferential spout (8) is 311III, and the total cross-sectional area of the spout (8) and auxiliary channels (5) and (6) is 5.
34 Maro 3 and Atsuka.

9. Conduct experiments under three different water pressures (P).

Water flow 1 (Q), flow velocity (V 1) in the discharge pipe (11)
, the flow velocity at the spout (8) 0'I), the height A) of the water curtain and its width (V) are shown in the following table.

[Brief explanation of the drawing]

FIG. 1 is a front view showing an example of the water curtain forming device of the present invention, FIG. 2 is a perspective view of the water curtain forming device of FIG.
FIG. 5 is a partial front view showing another example of the auxiliary waterway of the water curtain forming device of the present invention. 1: water discharge pipe, 5: long vertical groove 6: short vertical groove, 7: backing plate 8: semicircular spout. 5/, 8/I independent and auxiliary waterway

Claims (1)

[Claims] L For a backing plate! A water curtain characterized in that an upward semicircular ejection hole is formed at the tip of the adjacent water discharge pipe, and a plurality of auxiliary water channels are provided in the center along the skeleton semicircular ejection hole. Forming device. 2. The water curtain forming device according to claim 1fJL, wherein the auxiliary water channel comprises a plurality of vertical grooves, one end of which is connected to the semicircular jet hole and extends in the axial direction of the water discharge pipe. The water curtain forming device according to claim 8, wherein the vertical grooves having different lengths are arranged alternately.