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Fuse-din precision thermometer
374
CURRENT TOPICS
[J. F. I.
Mica Mat for I n s u l a t i o n . - - M i c a mat, a new, paper-like material made of m a t t e d flakes of mica, is being used for ground insulation in the General Electric C o m p a n y ' s Locomotive and Car E q u i p m e n t Department, Erie, Pa. Developed in Europe, mica m a t is manufactured b y G.E. in a newlyadapted process similar to paper making. General Electric engineers point out t h a t the operation at Erie is one of the first American production uses oJ this type of ground insulation. Mica m a t is being used in both a r m a t u r e windings and field coils in the manufacture of some motors and generators for electric and diesel-electric locomotives at Erie. T h e new material will stand about 600 volts per mil of thickness, G.E. engineers say. Its thickness is uniform within a fraction of a rail, and the thickness of a taped or wrapped conductor is now more constant than was possible with mica-glass cloth insulation. Engineers point out that mica mat also has fewer electrical "holes" than mica-glass cloth. T h e manufacture of the new material, G.E. engineers explain, is done by baking mica at 700-8000C. and then suddenly quenching it with cold water, causing the mica to explode into tiny flakes. The water-mica slurry is then fed into a paper-making machine and comes out as a dry, fragile paper. This paper is impregnated with a heat-resisting silicone varnish and applied to glass cloth for use as wrappers. Engineers add t h a t the finished product meets the specifications of class " H " insulation. F u s e - D i n Precision Therrnometer.--To satisfy the demand for a precision thermometer which is not as brittle as conventional platinum and glass thermometers, an Armored Precision T h e r m o m e t e r has been designed b y Weiller Instruments Corporation, New York City. T h e over-all length of this Fuse-Din Armored Precision T h e r m o m e t e r is 141 in. It is protected b y a stainless-steel tube ~ in. o.d. T h e thermometer head is 1 in. in diameter and 12 in. long. T h e four terminals are fused into a disc of borosilicate glass. Several types of Fuse-Din Precision Thermometers are available in this form. For temperatures up to 300°C., T y p e P B M , cast in lead thermometer, is recommended. T h e resistance unit is tungsten, fused into pryex. For higher temperatures up to 400°C., the same resistance thermometer is available, cast in zinc. Internal leads m a y be silver or gold, depending on the user's requirements. T o permit precision measurements up to a temperature of 1500°C., T y p e P P C is used. This is a platinum thermometer, fused into a ceramic matrix. T h e internal leads are platinum.
A special escape capsule for supersonic planes has been developed by the N a v y Bureau of Aeronautics, has been successfully tested in wind-tunnel speeds of over 1200 mph. T h e unit is pressurized, contains oxygen equipm e n t and a para-raft, can be used in fighter or multi-place planes. T h e capsule is constructed of armor plating and laminated fiberglass, thus protecting against fire and flak, will float, and can be fitted with heating unit for use in frigid areas. T h e parachute, in a reefed condition, acts as a stabilizer during the drop until a barometric control lets it open to full diameter to cushion the landing. N a v y stresses fact that this capsule is not in competition with ejection cockpit capsule formerly announced, which is for persons in the cockpit only.
CURRENT TOPICS
[J. F. I.
Mica Mat for I n s u l a t i o n . - - M i c a mat, a new, paper-like material made of m a t t e d flakes of mica, is being used for ground insulation in the General Electric C o m p a n y ' s Locomotive and Car E q u i p m e n t Department, Erie, Pa. Developed in Europe, mica m a t is manufactured b y G.E. in a newlyadapted process similar to paper making. General Electric engineers point out t h a t the operation at Erie is one of the first American production uses oJ this type of ground insulation. Mica m a t is being used in both a r m a t u r e windings and field coils in the manufacture of some motors and generators for electric and diesel-electric locomotives at Erie. T h e new material will stand about 600 volts per mil of thickness, G.E. engineers say. Its thickness is uniform within a fraction of a rail, and the thickness of a taped or wrapped conductor is now more constant than was possible with mica-glass cloth insulation. Engineers point out that mica mat also has fewer electrical "holes" than mica-glass cloth. T h e manufacture of the new material, G.E. engineers explain, is done by baking mica at 700-8000C. and then suddenly quenching it with cold water, causing the mica to explode into tiny flakes. The water-mica slurry is then fed into a paper-making machine and comes out as a dry, fragile paper. This paper is impregnated with a heat-resisting silicone varnish and applied to glass cloth for use as wrappers. Engineers add t h a t the finished product meets the specifications of class " H " insulation. F u s e - D i n Precision Therrnometer.--To satisfy the demand for a precision thermometer which is not as brittle as conventional platinum and glass thermometers, an Armored Precision T h e r m o m e t e r has been designed b y Weiller Instruments Corporation, New York City. T h e over-all length of this Fuse-Din Armored Precision T h e r m o m e t e r is 141 in. It is protected b y a stainless-steel tube ~ in. o.d. T h e thermometer head is 1 in. in diameter and 12 in. long. T h e four terminals are fused into a disc of borosilicate glass. Several types of Fuse-Din Precision Thermometers are available in this form. For temperatures up to 300°C., T y p e P B M , cast in lead thermometer, is recommended. T h e resistance unit is tungsten, fused into pryex. For higher temperatures up to 400°C., the same resistance thermometer is available, cast in zinc. Internal leads m a y be silver or gold, depending on the user's requirements. T o permit precision measurements up to a temperature of 1500°C., T y p e P P C is used. This is a platinum thermometer, fused into a ceramic matrix. T h e internal leads are platinum.
A special escape capsule for supersonic planes has been developed by the N a v y Bureau of Aeronautics, has been successfully tested in wind-tunnel speeds of over 1200 mph. T h e unit is pressurized, contains oxygen equipm e n t and a para-raft, can be used in fighter or multi-place planes. T h e capsule is constructed of armor plating and laminated fiberglass, thus protecting against fire and flak, will float, and can be fitted with heating unit for use in frigid areas. T h e parachute, in a reefed condition, acts as a stabilizer during the drop until a barometric control lets it open to full diameter to cushion the landing. N a v y stresses fact that this capsule is not in competition with ejection cockpit capsule formerly announced, which is for persons in the cockpit only.