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high-pressure hydraulic pump
high-pressure hydraulic pump

high-pressure hydraulic pump

Date1924-1937
Inventory Number1997-1-1819b
ClassificationHydraulic Pump
Subject
    Maker Percy Williams Bridgman 1882 - 1961
    Manufacturer Crosby Steam Gage & Valve Company fl. 1880s - 1930s
    Cultural Region
      Place of Origin
        Dimensions107 x 44 x 113 cm (42 1/8 x 17 5/16 x 44 1/2 in.)
        Material
          Accessories4 wrenches; 1 oil pan
          DescriptionSupported by a four-leg structure, this hand-activated pump is made of steel and is still oily. The pressure is built-up inside the rectangular steel compressing chamber by moving the lever up and down. Pressure is then transmitted to a gauge and to a hydraulic press via copper tubings. On the side, there is another compressing chamber to which can be attached several tubes. It serves as a distribution node, so the high pressure could be transmitted to several places at the same time. The gauge's units are in lbs per square inch, from 0 to 15,000, the smallest division being 250.

          Above, a cylindrical vessel containing oil. One copper tube transports oil into the piston chamber to lubricate the piston; one tube extracts oil and transports it back into the vessel. There was thus a continuous flow of oil going in and out of the high-pressure chamber. Excess of oil was collected into a metallic pan hooked underneath the chamber.

          Except for the pressure gauge, this pump was shop-built at Harvard by Bridgman's mechanic, Charles Chase. It is a Cailletet-type pump.
          Signedon gauge: CROSBY / BOSTON, U.S.A. / AIH / LBS. PER. SQ. INCH on 3 wrenches: Williams / FORGED IN USA on 1 wrench: The Billings / & Spencer Co / FORD. CONN. USA on 4 structure joints: MADE IN / WALWORTH / USA
          Inscribedon tag: 5/66 on tag: Basement
          Curatorial RemarksThough this pump may well have been built circa 1924, it is possible it was built later, to be used with the more powerful hydraulic press in the middle of the 1930s.
          FunctionThis high-pressure pump was used together with a hydraulic press, with which experiments were conducted on metals and other meterials under high pressures. Bridgman, for instance, measured compressibilities, electrical resistances, viscosities and later, with the higher pressure apparatuses, the effect of pressure on the mechanical strength and ductility of these substances (which were very large).

          Percy Bridgman conducted high-pressure experiments in the 1920s that ranged between 12,000 and 20,000 atmospheres (12,000-20,000 kg/cm²). Two such pumps were required to generate this effect, which was used with the hydraulic press #1997-1-1819d. In the second half of the 1930s, Bridgman expanded his range of pressures with a more powerful hydraulic presses, reaching between 30,000 and 50,000 atms (see #1997-1-1819a). To achieve this higher pressure, two and even three hand-pumps were required, each activating a separate compressing piston.

          ProvenanceJefferson Physics Laboratory, Harvard University
          Historical AttributesThe CHSI also has many samples produced by Bridgman's high pressure experiments with apparatuses like this one.
          high-pressure hydraulic pump
          Percy Williams Bridgman
          Date: 1924-1937
          Accessories: pressure-broken metal samples; parts for hydraulic press
          Object number: 1997-1-1819c
          Bridgman press
          Percy Williams Bridgman
          Date: 1924-1937
          Accessories: cardboard box of spare parts; rubber tube; yellow hand pump; metal wire; torque wrench; wrenches (3); 1 CD; 1 audio cassette; 1 user's manual; 1 graph
          Object number: 2004-1-0404
          Spare parts for Bridgman press box 1 of 2
          Percy Williams Bridgman
          Date: 1924-1937
          Object number: 2004-1-0404.1
          Spare parts/tools for Bridgman press Box 2 of 2
          Percy Williams Bridgman
          Date: 1924-1937
          Object number: 2004-1-0404.2
          wrenches for Bridgman press
          Percy Williams Bridgman
          Date: 1924-1937
          Accessories: two boxes of parts/tools for bridgman press (.1 & .2)
          Object number: 2004-1-0404.3
          Timing weights for use with Shortt and Synchronome clocks.
          William Hamilton Shortt
          Date: circa 1929
          Object number: 1998-1-0187a
          CENCO hydraulic press, partial
          Central Scientific Company
          Date: circa 1930
          Object number: 2008-1-0181
          double-barreled air pump
          W. & S. Jones
          Date: circa 1804
          Object number: 0021
          ionization chamber
          Harvard Cyclotron Laboratory
          Date: 1980-1984
          Object number: 2003-1-0294
          high-pressure hydraulic press
          Percy Williams Bridgman
          Date: circa 1924
          Accessories: high-pressure compressing chamber
          Object number: 1997-1-1819d
          ionization chamber
          Harvard Cyclotron Laboratory
          Date: 1960-1984
          Object number: 2003-1-0302
          steam engine indicator, no. 121
          Crosby Steam Gage & Valve Company
          Date: circa 1897
          Accessories: small corked glass bottle containing "watch oil"; screwdriver; elbow; mahogany handled stopcock
          Object number: 1996-1-0251