GB637306A - Improvements in apparatus for testing the bursting strength of papers and other sheet material - Google Patents

Abstract

637,306. Testing physical qualities of materials. BALSTON, Ltd., W. & R., and BALSTON, F. W. March 19, 1947, No. 7583. [Class 106 (ii)] Apparatus for testing the bursting strength of paper, non-fibrous films and like sheet materials comprises a container for a fluid and having an outlet in combination with clamping means arranged to hold one side of the test piece at the outlet so as to close it in a fluidtight manner with the said side in direct contact with fluid flowing into the container to increase the pressure therein, while the opposite side of the test piece is exposed to atmospheric pressure and means for indicating and/or recording the pressure of the fluid in the container when the test piece bursts..The test sheet 34 is held over an aperture in a plug 24 secured to a tube 16 by an apertured clamp 50 carried by a pivoted arm 36 engageable by a pivoted hand-lever 44. Water is fed into the tube 16 through an inlet 60 until the specimen bursts, when the pressure is indicated by a float 70 secured by a wire 68 passing over one or more pulleys 66 to a counterweight 72 of identical mass, the height of which may be read against an adjustable scale 62. With the float in its zero position, the weight 72 is adjusted on its threaded rod 76 until it exactly fits in a bracket 86 and the weight 72 may be used as a bob co-operating with an index 88 on a lower bracket when levelling the tripod support 12 for the apparatus which may then be clamped to a baseboard or the like. When testing stronger sheets, a gaseous fluid is used and the pressure is measured by one or more pressure gauges of different ranges connected through stop-cocks to the top of the tube 16 in place of plugs 114, a cap which screws on to a thread 112 serving to close the tube 16. The pulleys 66 are carried by a bracket which has a bayonet-joint connection to the support 12 so as to be readily removable. In a modification for use at high pressures only, the support 12 and tube 16 are short and the latter is permanently closed by a cap having connections to one or more pressure gauges. Specification 221,234, [Class 106 (ii)], is referred to.