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Welding-site conditions and welding-wire diameter govern efficiency and size of power supply required for a job. Select a 100-A unit that runs from single-phase 115-V input for low-duty-cycle welding of sheet to l/s in. thick, feeding wire to 0.030-in. diameter. Medium-duty power supplies, 150-200 A, normally take single-phase 220-V input drillpressbasecabinet to weld drillpressbasecabinet steel to 3/16, in. drillpressbasecabinet and 0.035-in. wire at low-duty cycles. For high-duty cycles, as in mechanized welding, select a 250-A machine, single or three-phase input at various voltages-these weld material to 1/2 in. thick with wire as large as 0.045-in. diameter. Taking three-phase input only and wire up to 1/6-in. diameter, 400-A units serve for mechanized continuous-welding applications. For pulsed GMAW, shops use inverter and transistor power sources, constant-current drillpressbasecabinet or constant-voltage, that offer independent setting of pulse parameters. They employ synergic controls preprogrammed for a range of wire-feed speeds-the operator sets only one dial, for average current. CONSTRUCTION: Bethlehem Steel Corp., Singapore,1975, Rebuilt, 1982; Modernized 1985.PERFORMANCE: Water depth--250''; Drilling depth--25,000''.QUARTERS: 74 persons, plus 3-man sick bay.HULL: 166'' x 132'' x 16''.HELIPORT: 83'' drillpressbasecabinet x 83''.STORAGE: Mud & Cmt Bulk--6,030 cf; Sackstorage--3,000 sks; Liquid Mud--1,800 bbl;Fuel--l,719 bbl; Water for Drilling 5,575 bbl; Potable Water--474bbl.DRILLING drillpressbasecabinet EQUIPMENT: Drawworks--Nat''l 1625DE, three 800 hp motors; Pumps--two Nat''l 12-P-160triplex, 1,600 hp; Prime movers--two EMD
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