JPS627969B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a quick-drying developing device used for liquid penetrant testing of steam generators and the like.

Liquid penetrant testing has high sensitivity to cracks and is considered indispensable for post-weld inspections. However, this inspection has traditionally been based on manual flaw detection, and there are significant technical problems in automating it, especially in quick-drying liquid penetrant flaw detection, which has not been automated at all.

That is, when performing quick-dry development, as shown in FIG. 1, the spray nozzle 1 is spaced about 30 cm from the surface to be inspected 2 to spray the developer, thereby ensuring that a uniform developed surface is obtained. Therefore, when attempting automation, this separation distance is a big problem, and the spraying time is also short, a few seconds, making it extremely difficult to control the spray.

In addition to this problem, the quick-drying developer also has the disadvantage that it dries and sticks, which tends to clog the spray nozzle and makes continuous operation difficult.

The present invention has been made in view of the above-mentioned circumstances, and its purpose is to spray only ultra-fine developer mist, eliminating the need to pay attention to the distance to the surface to be inspected, and achieving automation. Furthermore, the present invention provides a quick-drying developing device that can remove the developer remaining in the nozzle using high-pressure gas or liquid and prevent the developer from drying and sticking.

That is, the present invention has an air supply pipe and a developer supply pipe attached to one end of a cylindrical body containing a built-in gas-liquid mixing type spray nozzle, and a flexible guide pipe attached to the other end, and is switched to the developer supply pipe. The gist is that a cleaning pipe is connected through a valve, and the developer remaining in the spray nozzle is removed by high-pressure gas or liquid spouted from the cleaning pipe.

Embodiments of the present invention will be described in detail below based on the drawings.

FIG. 2 is an explanatory diagram showing the entire quick-drying developing device. This device has a flexible guide tube 12 attached to the tip of a cylindrical body 11, and a developing head 13 attached to the tip of this guide tube 12. , From here, test surface 1
4, a liquid mist of developer is sprayed.
Further, at the base end of the cylindrical main body 11, a developer supply pipe 15,
An air supply pipe 16, an air sweep pipe 17 for sending high-pressure air, and a drain pipe 25 are installed. Further, a switching valve 18 is attached to the developer supply pipe 15, and a developer supply pipe 19, a cleaning pipe 20 for sending high-pressure air, and a pair of piston operating hollow pipes 21a and 21b are attached to the switching valve 18.

As shown in FIG. 3, the cylindrical main body 11 is provided with a squeeze tube portion 11a having a gently tapered V-shaped cross section at its tip, and a guide tube 12 is attached through the squeeze tube portion 11a. Further, a gas-liquid mixing type spray nozzle 22 is built into the cylindrical body 11, and the developer supply pipe 1 is connected to the spray nozzle 22.
5 and an air supply pipe 16 are connected. Also, a liquid drain hole 23 is provided between the spray nozzle 22 and the inner wall of the main body.
is formed, and this drain hole 23 communicates with a drain pipe 25 via a space 24. Further, the air sweep pipe 17 opens into the space 24 .

Further, the switching valve 18 is provided with a liquid piston 26, and this liquid piston 26 is supported by a compression coil spring 2.
7 in the direction of arrow A, and by applying pressure from the piston operating hollow tubes 21a and 21b, the piston moves back and forth in the direction of arrow A and the direction of arrow B. Furthermore, the switching valve 18 is provided with liquid passages 28 and 29 that communicate with a developer supply pipe 19, and the liquid passage 29 communicates with a valve seat 31 through a small hole 30 provided at the tip of the liquid piston 26. , and further communicates with the liquid reservoir 32 and the developer supply pipe 15.
A poppet valve 34 which is normally closed by a compression coil spring 33 is attached to the liquid reservoir 32.
is communicated with the cleaning pipe 20 by opening the poppet valve 34. Note that 35 in the figure is a seal.

Next, the operation of the quick-drying developing device will be explained.

First, during development, when pressure is applied to the open piston actuating empty tube 21a, the liquid piston 26 moves in the direction of arrow B, the valve seat 31 opens, and the developer is transferred from the liquid passages 28, 29 to the valve seat 31 to the liquid. The developer passes from the reservoir 32 to the developer supply pipe 15 and is supplied to the spray nozzle 22. On the other hand, a spray nozzle 22 is connected from the air supply pipe 16.
air is supplied to. The developer and air thus supplied are mixed and sprayed to form a liquid mist.
When this liquid mist hits the inner wall of the main body 11, most of it is liquefied again and flows down the inner wall, passes through the drain hole 23 and the space 24, and is discharged from the drain pipe 25, as shown in FIG. In this case, coarse particles tend to be more easily liquefied, and the coarse particles and fine particles in the liquid mist are separated here. Further, since the recondensed liquid can be retained in the space 24, the tip of the spray nozzle 22 is prevented from becoming below the liquid level.

Next, the liquid mist that did not hit the inner wall of the main body 11 and the liquid mist made up of relatively fine particles that did not liquefy even after collision are guided to the guide tube 12, and repeatedly collide with and leave the inner wall. is liquefied, passes through the pipe wall, passes through the main body 11, and is discharged from the drain pipe 25. Even in this case, since coarser particles tend to liquefy more easily, only ultrafine particles remain until they reach the developing head 13, and a uniform fine liquid mist is sprayed from the tip.

In this way, a uniform fine liquid mist is sprayed,
High-sensitivity development is possible without particularly setting the distance to the surface to be inspected 14.

Next, when the development is completed, pressure is applied from the closing piston operating hollow pipe 21b to move the liquid piston 26 in the direction of arrow A, close the valve seat 31, and stop supplying the developer.

Next, when high pressure air or liquid is supplied to the cleaning pipe 20, the poppet valve 3 resists the spring force.
4 opens, and the high-pressure air instantly removes the developer remaining in the liquid reservoir 32, the developer supply pipe 15, and the spray nozzle 22, thereby preventing the developer from sticking.

Furthermore, when high-pressure air is supplied to the air sweep pipe 17, the developing solution adhering to the inner wall of the main body 11 is peeled off and separated, thereby preventing the passage from being narrowed due to the adhesion of the adhering liquid. Therefore, since the developer can be removed satisfactorily, development can be carried out continuously.

Further, since these operations are carried out through the developer supply pipe 15, air supply pipe 16, piston operating hollow pipes 21a, 21b, cleaning pipe 20, and air sweep pipe 17, remote automatic operation can be performed.

As explained above, according to the present invention, high-sensitivity development can be performed by spraying only a uniform fine liquid mist, and continuous development can be performed by remote automatic operation. This is extremely effective in ensuring the safety of workers.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of a conventional developing device, FIG. 2 is an overall explanatory diagram of a developing device showing an embodiment of the present invention, and FIGS. 3 and 4 are cutaways of different essential parts of the same developing device. The enlarged side view shown in FIG. 5 is an explanatory view of the operation of the developing device. 11... Cylindrical main body, 12... Guide tube, 13...
...Development head, 14... Test surface, 15, 19...
Developing solution supply pipe, 16...Air supply pipe, 17...Empty sweeping pipe, 18...Switching valve, 20...Cleaning pipe, 21a, 21b...Piston operation empty pipe, 22
...gas-liquid mixing type spray nozzle, 28, 29...liquid passage, 34...pouch valve.

Claims (1)

[Claims] 1 Attach an air supply pipe and a developer supply pipe to one end of a cylindrical body containing a built-in gas-liquid mixing spray nozzle, and a flexible guide pipe to the other end, and connect the developer supply pipe to the developer supply pipe via a switching valve. A quick-drying developing device, characterized in that a cleaning pipe is connected to the spray nozzle, and the developer remaining in the spray nozzle is removed by high-pressure gas or liquid spouted from the cleaning pipe.