JPH11237300A - Drum can leakage inspection device due to differential pressure method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To relatively easily and automatically detect the leakage of a drum can. SOLUTION: A leakage inspection device is provided with a pressurization pipe 3 that connects a reference drum can 1 without any leakage and a drum can 2 to be inspected and has a shut-off valve 5 in the middle, a pressurization line 4 for supplying a pressurization gas to the pressurization pipe 3, a differential pressure meter 8 for measuring a differential pressure across the both terminals of the shut-off valve 5 of the pressurization pipe 3, and a judging device 9 for detecting the leakage of the drum can to be inspected according to the measurement value of the differential pressure meter 8. The judging device 9 judges that the drum can 2 to be inspected leaks when a differential pressure is 0.0006 kgf/cm<2> or larger when 60 seconds pass after the differential pressure is measured.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a drum leakage inspection apparatus for detecting leakage of a container such as a drum by a differential pressure method.

[0002]

2. Description of the Related Art Steel drums are packed with various products, whether liquid or solid, and are used for transportation and storage. Used drums are appropriately removed of residues, washed, shaped, painted, and replaced with necessary parts, etc., and then put back on the market as containers for transporting and storing products.

[0003] A drum can is formed by joining a top plate and a main plate to a body, and this joined portion is called a winding portion. A used drum can leaks from a pinhole generated by the tightened portion or rust, and only the cans that have passed the leak inspection are put on the market. As a test method, after pressurizing a healthy drum can and a drum can to be tested to a constant pressure, visually measure the differential pressure between both drum cans with a differential pressure gauge. Was determined to have occurred.

[0004]

However, in the method of determining the pressure difference as described above, it takes two to three minutes or more to determine that the differential pressure has occurred due to the leakage, and it is desired to reduce the measurement time. Was rare. In addition, such detection is performed visually, and automation has been strongly desired.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has as its object to provide a drum can leak inspection apparatus by a differential pressure method for automatically and relatively quickly detecting a drum can leak.

[0006]

Means for Solving the Problems To achieve the above object,
Therefore, according to the first aspect of the present invention, a reference drum having no leakage is detected.
Pressurizing pipe connecting the drum to be inspected and having a shut-off valve in the middle
And a pressurizing line for supplying pressurized gas to the pressurizing tube, and
A differential pressure gauge that measures the differential pressure across the pressure valve shutoff valve;
Detects leaks from inspection target drums based on differential pressure gauge measurements
And a determining device for measuring the differential pressure after the differential pressure measurement.
The differential pressure when 60 seconds have passed is 0.0006kgf / cm ^TwoAbove
In this case, it is determined that the inspection target drum can has leaked.

The minimum pinhole diameter which can be clearly detected within 60 seconds by the differential pressure method was confirmed by a test and found to be 60 μm. Below this diameter, the differential pressure hardly changes over time, but if there is a pinhole with a diameter of 60 μm, the differential pressure rises with the passage of time and increases.
It turned out that the difference could be measured in seconds. Note that a test pressure of 0.1 to 0.3 kgf / cm ² is applied. According to this data, the differential pressure at 60 seconds after the differential pressure measurement was 0.
When it became 0006 kgf / cm ² or more, it became possible to judge that the drum to be inspected had a leak.

[0008]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a diagram showing a configuration of a leakage inspection device using a differential pressure method according to the present embodiment. Reference numeral 1 denotes a reference drum without leakage, and reference numeral 2 denotes an inspection drum to be inspected. Reference numeral 3 denotes a pressurizing tube having a solenoid valve 5 with a pressurizing tube in the middle,
Test pressure (0.1 ~
0.3 kgf / cm ² ) is applied. A pressurizing line 4 is connected to the pressurizing pipe 3 and has a solenoid valve 6 with a pressurizing line, and is supplied with pressurized air from an air source 7. A differential pressure gauge 8 is connected so as to take pressure on both sides of the solenoid valve 5 with a pressurized pipe, and an output of the differential pressure gauge 8 is connected to a computer 9 (judgment device). A monitor 10 is connected to the computer 9 and displays a measured value of the differential pressure and a leak determination result.

To measure the differential pressure, first, both solenoid valves 5 and 6 are opened, pressurized air is supplied from an air source 7 to both drums 1 and 2, and when the test pressure is within the range, a solenoid valve with a pressurizing line is first provided. 6
Is closed, and then the solenoid valve 5 with the pressure tube is closed. Solenoid valve 5
When the inspection drum 2 is leaked and closed, a differential pressure is generated over time. When the differential pressure at 60 seconds after the solenoid valve 5 is closed becomes 0.0006 kgf / cm ² or more, it is determined that the inspection target drum 2 has leaked.

FIG. 2 shows the results of an experiment performed to set a criterion. 0μm, 40μm, 60μ pinhole diameter
Test drums of m, 150 μm, 212 μm, and 450 μm were prepared, and each of these test drums and the reference drum were mounted on the apparatus shown in FIG. is there. When the pinhole diameter is 0 μm or 40 μm, the change in the differential pressure does not clearly appear over time, but when the pinhole diameter is 60 μm, the change in the differential pressure clearly appears over time. 60 at this time
The leakage of the drum can is detected using the differential pressure of 0.0006 kgf / cm ² in seconds as a criterion.

[0011]

As is apparent from the above description, according to the present invention, a criterion which can be determined in a short time when detecting the leakage of the drum by the differential pressure method is set. Can be detected. In addition, since the test results are performed by a computer, there is no variation in the inspection as compared with the case of performing the test visually.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating a configuration of an entire apparatus according to an embodiment.

FIG. 2 is a diagram showing a test result for determining a criterion for determining whether leakage is possible.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 Reference drum can 2 Inspection drum can 3 Pressurizing pipe 4 Pressurizing line 5 Solenoid valve with pressurizing pipe 6 Solenoid valve with pressurizing line 7 Air source 8 Differential pressure gauge 9 Computer 10 Monitor

Claims (1)

[Claims] 1. A pressurizing pipe having a shut-off valve connected between a reference drum can having no leakage and a drum can to be inspected, a pressurizing line for supplying pressurized gas to the pressurizing pipe, and a shutoff valve of the pressurizing pipe. A differential pressure gauge that measures the differential pressure at both ends; and a determining device that detects leakage of the inspection target drum from the measured value of the differential pressure gauge. A drum pressure leak inspection device using a differential pressure method, which determines that a drum to be inspected has a leak when the pressure becomes 0.0006 kgf / cm ² or more.