JPS58106433A - Inspecting tool for leakage of long cylindrical member - Google Patents

Abstract

PURPOSE:To shorten leakage inspecting operation time by fixing an annular casing consisting of plural blocks windingly through a band and forming annular negative pressure spaces around the circumferential seam of a long cylinder part. CONSTITUTION:The annular casing 20 is positioned at the seam 2 of welding of the long cylindrical tube 1; and the band 37 is run in grooves 26 and 27 by using a handle 44 and a wind engaging hole is engaged with a hook 42. Consequently, for example, three blocks 21-23 constituting the annular casing 20 are held around the outer circumference of the tube 1. In this state, when a worm shaft 34 is rotated through the handle, a worm wheel 41 is driven to secure the band 37; and sealed spaces 47-49 are formed around the outer circumference of the tube 1 of the blocks 21-23 and evacuated by a vacuum pump, etc., to obtain annular negative pressure spaces where no external air is entered. If leakage occurs in the tube 1, gas such as helium in the tube 1 is sucked by the vacuum pump together with air and thus detected. Consequently, even if the tube is long, the inspection is speeded up to shorten leakage inspecting operation time.

Description

[Detailed description of the invention] The present invention relates to a tool for detecting leakage in a cylindrical member.

The most reliable inspection method for detecting minute leaks in welded parts (generally circumferential welded joints) of pipes and the like is the vacuum cover method. In this method, the welded part to be inspected is surrounded by a helium root, etc., and helium gas is put inside the pipe.At the same time, the air inside the tube is sucked out and sent to the helium tester.

Leakage is detected based on the presence or absence of helium content.

However, there are drawbacks such as a long detection time when the pipe to be inspected is very long.

The present invention has been made in view of the drawbacks of the conventional methods.Helium gas is introduced into the long cylindrical member that is the object to be inspected, and the internal gas is sucked out from the sealed space defined outside the part to be inspected. and provides tools for testing for leaks.

The inspection tool according to the present invention has an annular casing consisting of at least two arcuate blocks.

Therefore, it is easy to attach and detach from the object to be inspected, and the volume of the defined annular space can be made small regardless of the length of the object to be inspected, which is extremely effective in reducing the time required for leakage inspection work.

The present invention will be explained below based on illustrated embodiments.

FIG. 1 is a partial cross-sectional view of an inspection tool 10 according to the present invention.

In the figure, 1 is a cylindrical pipe which is the object to be inspected, and has two circumferential welded seams 2, and this is the part to be inspected for leakage.

The annular casing 20 is an arcuate block 2 having the same shape.
1,22.28, block 22 is block 23
It is rotatably connected to the block 28 by a hinge 24 and a pin 25 fixed to the block 28 .

Similarly, the block 21 is connected to the block 23 via a hinge 24, and when the casing 20 is removed from the pipe 1, it is opened from the joint of the blocks 21 and 22.

At this time, the blocks 21 and 22 rotate around the pin 25.

Grooves 26 and 27 are formed on the outer periphery of the blocks 22 and 21, respectively, and the worm shaft 34 is attached to the support 29 whose lower part is inserted and fixed into the socket 27 via bushes 81 and 82. There is.

A thread 85 inserted through the tip of the worm shaft 34 is used for tightening a band, which will be described later.

The proximal end of a band 37 is attached to the leg on the left side (in FIGS. 1 and 3) of the flock port 29, and this band 37 is attached to the leg 27 of the flock 21. Block 22 Lecture 2
6 and the block 23 through an unillustrated groove.

The worm 5 and the worm 39 of the worm shaft 34 are engaged with the worm 39. The worm wheel 41 has an arc-shaped part with a circumference of about 1/6 and is in sliding contact with the bottom of the worm 27 of the worm 21, and has a hook at its tip (the right end in the figure). 42 is formed.

As shown in FIG. 4, a hook hole 45 is bored at the tip of the bunt 37 with a handle 44 attached thereto, and when the casing 20 is taken, a hook 42 is inserted into the hook hole 45 as shown in the figure. There is.

Inside the blocks 21, 22, 28 are respectively defined arcuate spaces 47, 48, 49 which are open at both ends, and define an annular space in the attached state as shown in FIG.

In the grooves formed on the inner circumferential surfaces and both end mating surfaces of the flocks 21, 22, 28, gaskets l having the shape shown in the perspective view of FIG.
-51 is fitted, and furthermore, a nostle 52 that communicates with the space 47 is protruded from the block 21, and this is connected to a suction device M (not shown) via a hose or the like during inspection.

The structure of the T tool 10 in the E-mounted state has been described above, but first, the mounting work will be explained.

With hook 42 and band 37 removed.

Block 22. '2B is hanging down from block 21.

The casing 20 is positioned so that the joint 2, which is the part to be inspected, is surrounded by the arcuate space 47°48.49, and the blocks 21 and 2228 are held along the outer surface of the tube 1. At the end, while holding the state of ＼, hold the handle 44 of the band 8.
7 through the grooves 26 and 27, and wind it through the hole 45 with the hook 4.
Hang on to 2.

Next, grab the handle 85 and turn the worm shaft 84.
The worm wheel 41 meshed with the worm 39 moves to the left in FIG. 2 and tightens the band 37.

Further, to explain the state in which a leakage test is performed using the tool 10, the tube 1 is filled with helium gas.

By means of a suction device (not shown), for example a vacuum pump.

The air in the spaces 47, 48, 49 is drawn, and since the rings touch each other and the outer surface of the tube 1, no external air enters into the spaces 47, 48, 49.

If there is a leakage point due to a welding defect or the like at or near the seam 2, the helium gas inside will leak into the space 47°48.49, and the leaked helium scum will be drawn by the vacuum pump and sent to the helium detector.

That is, the presence or absence of leakage at the joint 2 is inspected based on the presence or absence of leaked helium scum.

The tool 10 can be removed by reversing the above-described operation.

According to the embodiment described above, the T-tool 10 can be easily attached and detached, and the spaces 47, 48, and 49 are set to the minimum necessary size, so the inspection work including the vacuuming work can be completed in an extremely short time. I can do two things. Especially when the tube 1 is long, the effect of shortening the inspection work time is extremely large compared to the conventional tube.

[Brief explanation of the drawing]

Fig. 1 is a front view of the second embodiment of the present invention, Fig. 2 is a side view, Fig. 3 is a plan view, Fig. 4 is a partially detailed view of the embodiment, and Fig. 5 is a detailed view of the embodiment. It is a heron perspective view showing - of a component. 1...Pipe, 2...Joint, 10...Tool, 20...
・Annular casing, 21, 22, 28...block. 24... Hinge, 25... Pin, 26.27...
groove. 29... Support l-, 81, 82... Bunyu, 8
4... Worm l1ld1.85... Handle, 8
7...Band. 89...worm, 41...worm wheel. 42...Hook, 45...Hole for hanging, 47,48°4
9... Space, 51... Nozzle, 52... Caskerato.

Claims (1)

Claims: An annular caning comprising at least two arcuate blocks and selectively defining an annular space inside. A tightening member including a band wound in contact with the outer peripheral surface of the casing and attached to one of the blocks, and a nozzle penetrating through at least one of the blocks and extending outward and communicating with a suction device. A leakage inspection tool for an elongated cylindrical member, which is attached to the outer surface of an elongated cylindrical part shrine having one circumferential joint and defines a negative pressure annular space around the circumferential joint.