Welch

Welch

  • Welch 1399 DuoSeal Belt Drive Vacuum Pump with Dayton capacitor-start motor mounted on base plate — left side view Welch 1399 DuoSeal Vacuum Pump rear and belt guard view showing dual belt covers and inlet/outlet fittings

    Welch 1399 DuoSeal Belt Drive Vacuum Pump 1/3 HP 115/230V 1725 RPM

    Welch

    $575.00
    Was: $1,200.00
    Welch 1399 DuoSeal Belt Drive Vacuum Pump 1/3 HP 115/230V 1725 RPMThe Welch 1399 is a belt-driven rotary vane vacuum pump designed for laboratory and industrial evacuation applications. The belt...
    47981
    SKU:
    47981
    Availability:
    In stock and ready to ship within 1-2 business days.
    Weight:
    65.00 LBS
    Brand:
    Welch
    Model:
    1399
    MPN:
    1399
    Type:
    Belt Drive Rotary Vane Vacuum Pump
    SKU:
    47981
    Motor Brand:
    Dayton
    Motor Model:
    4K929
    Motor Type:
    Capacitor Start A.C. Motor
    Horsepower:
    1/3 HP
    Voltage:
    115/230V AC
    Current Rating:
    6.8A (115V) / 3.4A (230V)
    Speed:
    1725 RPM
    Frequency:
    60 Hz
    Phase:
    Single Phase
    Motor Frame:
    48
    Insulation Class:
    Class A
    Drive Type:
    Belt Drive
    Current Wiring:
    115 VAC
    Pump Series:
    DuoSeal
    Manufacturer:
    Sargent-Welch Scientific Co.
    Seller Notes:
    Oil drained and not included. Wired for 115V, can be rewired for 230V.
    Country/Region of Manufacture:
    United States
    Form Factor:
    Benchtop
    Application:
    Laboratory, Scientific, Industrial Vacuum
    Review Status:
    Auto-Approved (needs review) 2026-07-04
    Condition Notes:
    Welch 1399 DuoSeal vacuum pump tested and in working order—powers on and produces vacuum. Currently wired for 115V; can be rewired for 230V. Oil drained, not included. Shows typical lab wear; may need servicing to reach factory specs.
    $575.00
    Was: $1,200.00
  • Welch Duo-Seal belt-drive vacuum pump mounted on steel base frame with Dayton motor and pulley assembly – front view Welch Duo-Seal pump head and oil sight glass detail – side view showing pump body

    Welch Duo-Seal Belt-Drive Oil-Sealed Vacuum Pump 3/4 HP 115/208-230V 1725 RPM

    Welch

    $750.00
    Was: $1,500.00
    Welch Duo-Seal Belt-Drive Oil-Sealed Vacuum Pump 3/4 HP 115/208-230V 1725 RPMThe Welch Duo-Seal is a classic oil-sealed rotary vane vacuum pump with belt-drive design, widely used in laboratory,...
    46991
    SKU:
    46991
    Availability:
    Usually ships within 2–3 business days via freight.
    Weight:
    230.00 LBS
    Brand:
    Welch
    Model:
    Duo-Seal
    MPN:
    Duo-Seal
    Type:
    Belt-Drive Oil-Sealed Rotary Vacuum Pump
    SKU:
    46991
    Motor Brand:
    Dayton
    Motor Model:
    6K376D
    Motor Power:
    3/4 HP
    Motor Voltage:
    115V / 208-230V AC
    Motor Current:
    10.8A (115V) / 5.3-5.4A (208-230V)
    Motor Speed:
    1725 RPM
    Motor Phase:
    Single Phase
    Motor Frequency:
    60 Hz
    Motor Frame:
    H56
    Drive Type:
    Belt Drive
    Drive Belt:
    4L490 Demco
    Ultimate Vacuum:
    Less than 0.05 micron at 300 RPM
    Vacuum Achieved (Tested):
    Approx. -28 in Hg (measured at our facility)
    Oil Type:
    Duo-Seal proprietary oil (required)
    Pump Design:
    Oil-sealed rotary, vintage belt-drive
    Manufacturer Location:
    Chicago, IL, USA
    Country/Region of Manufacture:
    United States
    Power Requirements:
    115V or 208-230V AC, 60 Hz, Single Phase
    Form Factor:
    Benchtop / Base-Mounted
    Shipping Method:
    Freight – oil drained prior to shipment
    Seller Notes:
    Tested working at facility. Ships freight with oil drained. Buyer must add Duo-Seal oil before use.
    Review Status:
    Auto-Approved (needs review) 2026-07-04
    Condition Notes:
    Welch Duo-Seal belt-drive vacuum pump tested and working at facility, pulling approximately –28 in Hg. Age-related wear, paint loss, surface rust on motor pulley and flywheel, intact belt.
    Motor Horsepower:
    3/4 HP
    Motor Current (115V):
    10.8 A
    Motor Current (208-230V):
    5.3–5.4 A
    Motor Frame Size:
    H56
    Tested Vacuum Performance:
    Approximately –28 in Hg
    Manufacturer:
    W.M. Welch Mfg Co
    Country of Manufacture:
    United States
    Compatible Applications:
    Laboratory, industrial, HVAC degassing, lab research systems
    $750.00
    Was: $1,500.00