614 



THE INDIA RUBBER WORLD 



[September 1, 1913. 



embodied in the text of the specifications should be omitted from 

 such tracings. The ink should be black and the lines drawn 

 slightly heavier than ordinary in order that a clear reproduction 

 may result. If impracticable to show all of the illustrations desired 



on one sheet 5 inches x 8 inches, other parts required should be 

 arranged so as to appear on one or more other sheets of the 

 same size. The drawing itself should not go beyond the limits of 

 Vj inch from the edge of the 5 inch x 8 inch slieet. 



New Navy Department Specifications. 



THE Navy Department is now issuing a number of revised 

 specifications to supersede those hitherto in force. The 

 princi|)al features of those issued up to the present time, 

 so far as they relate to rubber, are shown below : 



RUBBER E^VR CUSHIONS FOR FIRE CONTROL INST.\r.L.\TIONS. 

 (Specification No. 17C3a, July 5, 1913.) 



Material: To be properly vulcanized and to be made from 

 a compound containing not less than 45 per cent, of washed 

 and dried fine Para rubber, not more than 3.5 per cent, of 

 sulphur, with the remainder suitable mineral fillers. 



Tests : Permanent elongation not e.xceeding 20 per cent., 

 tensile strength at least 2,200 pounds per square inch. 



GAUGE GL.ASS GROMMETS. 

 (Specification No. 33Gla, July 15, 1913.) 

 M.-\terial: Rubber compound — to be properly vulcanized and 

 to be made from a compound containing not less than 35 per 

 cent, of washed and dried fine Para rubber, not more than 2.5 

 per cent, of sulphur, with the remainder suitable mineral fillers. 

 Tests : Permanent elongation not exceeding 25 per cent., 

 tensile strength at least 1,500 pounds per square inch. 



SHEET P.\CKING, CLOTH OR WIRE INSERTION. 

 (Specification No. 33P4a, July 15, 1913.) 



Material : Rubber parts — rubber layers to be properly vul- 

 canized and to be made from a compound containing not less 

 than 25 per cent, of washed and dried fine Para rubber, not 

 more than 2 per cent, of sulphur, with the remainder suitable 

 mineral fillers. 



Tests: To bend double in any direction without cracking; 

 to stand four hours' exposure to boiling water without injury 

 to layers, and after four hours' exposure to steam at 150 pounds 

 pressure to show considerable flexibility. 



RUBBER HOSE FOR USE IN ENGINEERS' DEP.XRTMENT. 

 (Specification No. 341163, July 15, 1913.) 



Material: Cotton canvas layers of duck (three plies), free 

 from unsightly defects. 



Rubber parts : Tube, cover and washers to be properly vul- 

 canized and to be made from a compound containing not less 

 than 35 per cent, of washed and dried fine Para rubber, not 

 more than 3 per cent, of sulphur, with the remainder suitable 

 mineral fillers. 



Tests : Tests on the hose as a wliole to be as indicated in 

 general specifications for rubber material. 



Guar.\ntee: Manufacturers to guarantee hose to be made ac- 

 cording to best principles of construction and free from defects 

 of material and workmanship ; if defects shown within 2 years 

 the rubber parts to be replaced with new hose. 



IJi-INClI RUBBER HOSE. 

 (Specification No. 34H9a, July 15, 1913.) 



Material: Cotton canvas layers (three plies) free from un- 

 sightly defects. 



Rubber Parts : Tube, cover and washers to be properly vul- 

 canized and made from a compound containing not less than 

 35 per cent, of washed and dried fine Para rubber — not more 

 than 3 per cent, of sulphur, with the remainder suitable mineral 

 fillers. 



Tests: Tests on the hose as a whole to be as indicated in 

 general specifications for rul)ber material. 



Tests of Rubber Compound : Adhesion of friction coat of 

 rubber between plies to stand a weight of 15 pounds without 

 plies separating at greater rate than 1 inch per minute. 



Tube and Cover: Tensile strength at least 1,500 pounds per 

 square inch in tube and not less than 1,300 pounds per square 

 inch in cover. 



RUBBER PUMP V.\LVES. 

 (Specification No. 45V3a, July 15, 1913.) 



Materi.vl : Hard valves. To be properly vulcanized and to 

 be made from a compound containing not less than 30 per cent, 

 of washed and dried fine Para rubber, nor more than 10 per 

 cent, of sulphur. Remainder mineral fillers. 



Medium valves. To be properly vulcanized and made from 

 a compound containing not less than 35 per cent, of fine Para, 

 nor more than 5 per cent, of sulphur. Remainder mineral fillers. 



Soft valves. To be properly vulcanized and made from a 

 compound containing not less than 35 per cent, of fine Para 

 rubber, nor more than 2.5 per cent, of sulphur. Remainder 

 mineral fillers. 



Tests : Test on valves as a whole. \'alves taken at random 

 to stand a dry heat of 270° F. for one hour, and 400° F. in 

 saturated steam for three hours, without disintegrating or 

 blistering. 



SHEET RUBBER TILING. 

 (Specification No. 59Tla, July 15, 1913.) 



Construction : To be built up in two layers, ' s inch thick 

 with backing of 10-ounce cotton duck. 



!M.\teri.\l: Top layer to resist ordinary wear. Bottom layer 

 of black India rubber, acting as cushion for top layer. Backing 

 of 10-ounce duck free from unsightly defects. 



Tests : Top layer, special test for elasticity. Bottom layer, 

 special test for stretch. Cotton canvas backing, special test for 

 being firmly secured to back of tiling. 



RUBBER LIFE BELTS. 

 (Specification No. 12Bla, March 31, 1913.) 



Material: The fabric to be of the best quality rubber and 

 cotton drill, the rubber having not less than 60 per cent, pure 

 Para rubber. 



Test: .-\ir pressure test of 5 pounds to the square inch for 

 8 hours. To support 20 to 22 pounds dead weight in water. 



Guarantee : Three years. 



RUHIiER M.\TTING. 

 (Specification No. 28M2a, July 15, 1913.) 

 Material: The rubber face made from a properly vulcanized 

 rubber compound free from fiber, to show on analysis not more 

 than 60 per cent, mineral matter, not more than 6 per cent, 

 organic acetone extract, nor more than 6 per cent, sulphur. The 

 composition shall be free from objectionable odors. 



RUBBER FIRE HOSE. 

 (Specification No. 34H3a, July 30, 1913.) 

 Material : The tube, cover and washer shall be properly vul- 

 canized and have not less than 45 per cent, of washed and dried 

 fine Para rubber, not more than 3.5 per cent, of sulphur, with 

 the remainder suitable mineral fillers. 



Tests : The hose shall be tested as indicated in general speci- 

 fications for rubber material. 33 R. 3 (latest issue). 



