Waterproofness testing

Testing of detonators by Sand Test, Lead-Plate Test, Waterproofness Test and the Run-Down Test)... 

Waterproofness Test. The following test is contained in Military Standard-Fuze and Fuze Components, Environmental and Performance Tests for , MIL-STD-331A (15 Oct 1976). This standard establishes uniform environment and performance tests for use in the development and production of US fuzes and fuze components. Its purpose is to provide engineering in-... 

The waterproofness test is used during development of fuzes to check the ability of the fuzes to withstand submersion in shallow water. 

This waterproofness test is effective in determining whether the design of the fuze is adequate to withstand conditions of submersion which might be encountered, for instance, in a flooded magazine or a beach operation. 

Waterproofness Test for Use in Development of Fuzes Salt Spray (Fog) Test for Use in Production of Fuzes 5-ft Drop Test for Use in Production of Fuzes... 

The waterproofness test method for surgical dressings is described in the BP. The waterproofness test apparatus consists of the application of a hydrostatic head of 500 mm of water to a circular area about 20 cm of the nonadhesive side of the dressing. A filter paper (55 mm in diameter) is applied to the adhesive side. The dressing is deemed to comply with the waterproofness test if no water passes through it in at least five of a total of six specimens tested. 

The Kit Test (T-559 pm-96) can be used to measure oU repeUency when there is no physical barrier to oU penetration such as that provided by a film, foU, or waterproof coating (71). Another measure of oU repeUency is the Turpentine Test (T-454 om-89) (71). If a physical barrier is present, tests that measure the weight of oU pick-up or show-through under conditions that simulate the end use are appropriate. 

Further properties which a detonating fuse should have are the ability to initiate blasting explosives (tested with suitable relatively insensitive mixtures usually of TNT and ammonium nitrate) resistance to low temperatures without cracking on flexing and to hot storage without desensitisation and toughness to prevent damage from stones, etc. The fuse must always be waterproof and must often withstand diesel oil, which can separate from ANFO. 

A few miscellaneous tests that fall under neither input nor output characteristics, are surveillance tests, delay times, waterproofness, workmanship, duds, tumbling and some others... 

If the total elapsed time between original acceptance of any detonator (or primer) lot and assembly of that lot into the ammunition component with which it is issued exceeds two months or if the detonators (or primers) have been subjected to adverse conditions at any time since previous tests, the lot shall be subjected to, and must satisfactorily pass, the check test for sensitivity and waterproofness as described above. Should any lot fail the retests it shall be rejected... 

Immersion Test. This test, serving to check the waterproofness of packing, is conducted by immersing the packing in a tank of water at RT to a depth of 10 ft for ca 30 mins. Upon removal the packing is examined for evidence of leaking... 

Military Standard. "Fuze and Fuze Components, Environmental and Performance Tests for MIL-STD-331 (1966 1967) Class 100. Laboratory Tests - Jolt (101) Jumble (102) Forty-Foot Drop (103) Transportation Vibration (104) Temperature Humidity (105) Vacuum Steam Pressure (106) Salt Spray (Fog) (107) Waterproofness (108) Rain Test (Exposed Fuze Storage) (109) Fungus Resistance (110) Five-Foot Drop (111) Extreme Temperature Storage (112) Thermal Shock (113) Rough Handling (Packaged)... 

The chemical tests include Determination of the moisture and ash detection and determination of the dressing, qualitative test of the nature of the fibre, quantitative determination of the different kinds of fibre in the sample, investigation of the nature of the dye and of its fastness, determination of the nature and extent of the waterproofing, detection and estimation of the weighting of silk, and distinction between certain crude and bleached products. The methods used are as follows. 

A piece of the material is boiled in a reflux apparatus successively with ether, carbon tetrachloride, benzene, and alcohol, the treatment being stopped when the waterproofing material passes into solution in one of the solvents. This may be tested by ascertaining if the material treated in this way and well dried in the air has lost its impermeability totally or in part, and also by evaporating the extract in a porcelain dish on a water-bath and examining the residue the latter should consist of oil or fat, tar or fatty acids. 

Investigation of the Waterproofing Qualities.—The efficiency of the waterproofing may be tested as follows ... 

Ammonit V-3 v Poroshke (in powder). Contd AN (not waterproof) 82.0, TNT 16.5, asfal tit 1.0 paraffin 0.5%. Brisance 14mm Trauzl Test Value 360cc (Ref 112, p 52)... 

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