The spray rating tester comprises a metal framework allowing distilled water to be sprayed through a nozzle onto a test specimen at 45° and 150mm below the nozzle. The appearance of the specimen is compared against an standard photographic scale.A certain volume of distilled water is sprayed into the center of the fixed sample.
Before testing is carried out the specimen shall be conditioned for at least 24hours in the standard atmosphere. Water sprayed against the taut surface of a test specimen under controlled conditions produces a wetted pattern whose size depends on the relative repellency of the fabric.
-To carry out the test, first of all fasten the test specimens securely in the metal hoop of the water repellency tester so that it represents a smooth wrinkle free surface and place it face up on the tester.
-Adjust the metal hoop so that the centre of the spray coincides with the centre of the metal hoop. Later pour 250 ml of distilled water at normal temperature into the funnel and spray the whole quantity on the test specimen for a period of 25 - 30 sec.
-Now detach the metal hoop from the stand. Confirm whether water had penetrated to the back of the test specimen. With the face side of the test specimen down, hold the metal hoop by one edge and tap the opposite edge lightly once against the table.
-Then rotate it 180°C and similarly tap again once on the point previously held to remove any excess water drop.
-The final step is to compare the wetting of the test specimen with a photographic rating standard and grade it accordingly.
The Water Repellency Tester confirms with the international standards and comes under warranty. All this help provide customer satisfaction that promotes long term customer relationship which is our ultimate objective at B-Tex Engineering.
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