Leak Test Method and Warranty Coverage

When “No Leakage” is selected under the [Basic Information] menu in the Welded Sheet Metal Service, a leak test will be performed after welding.

Types of Leak Tests

Depending on the material and product shape, either a dye penetrant test or a snoop test will be selected and performed at the factory.

If you require a water-filling test, please specify this request in the Additional Instructions field and request a quote from meviy Support.

Color Check

The color check test method is described below.

①Remove any debris adhering to the product
②Apply color check to the welded area
③Apply the developer to the back side where the color check was applied
④Leave for approximately 30 minutes
⑤Visually inspect the weld area from the weld side for any red color reaction (leakage).

*During color checks, depending on the shape, the developer may flow around from the back side at the product edges or plate thickness surfaces. Therefore, even if there are no abnormalities in the weld quality, a red reaction may appear at the edges.

Schematic showing developer seeping into edges and causing red reactions at edges

Snoop Test

The test method for the Snoop test is described below.

①Remove any debris adhering to the product
②Apply Snoop solution to the welded area
③Blow air from the back side of the coated weld area
④Visually inspect for the presence of bubbles

*1 Spray for approximately 10 seconds per welded area to confirm

Scope of Leak Test Warranty

Applicable Product Usage Environments

The following products are covered by the guarantee for leak-free continuous welded joints and socket welded joints:

Products used indoors at temperatures between 10°C and 30°C
Products where no pressure is applied to the welded area
Products handling water and oil at temperatures between 11°C and 49°C
Applications involving the temporary storage or discharge of water and oil

Product usage environments not covered by warranty

The following product applications are not covered by warranty.

When used outside the indoor temperature range of 10°C to 30°C (e.g., in freezers or boiler rooms)
When used under pressure at the welded joint
When used with fluids other than water and oil (e.g., corrosive liquids such as sulfuric acid or liquid nitrogen)

Product Appearance After Leak Testing

During the color check, if a red reaction appears where the penetrant and
developer come into contact by penetrating the welded joint, the product is judged
to have a leak and will not be shipped.

Products that pass the leak test will have the penetrant and developer used in the color check wiped off before shipment.

Depending on the product shape, the dye color (red or white) may remain in areas

where wiping is difficult or on minor irregularities on the weld bead.

However, this does not affect the quality assurance of leak-free products.

Appearance before wiping

Appearance after wiping

Leak Test Warranty Provisions

Other warranty provisions for leak testing shall comply with the warranty provisions in the MISUMI Warranty Agreement