Designed specifically for vacuum distillations...
a superior new pump that ends costly corrosion and oil dilution problems! Here's a totally new vacuum pump for the organic chemist who per forms distillations in the range of Y2 mm. Hg. abs. and above. This quiet-operating, direct-driv en new pump eliminates irritat ing problems due to low boiling solvents, water and corrosive gases. True, traps remove most of these vapors and diluents before they've passed through a pump. How ever, some of these by-products sooner or later pass through the traps. In an ordinary vacuum pump, this fouls the oil and you have these irritating problems: (1) Pump vacuum decreases due to oil dilution; (2) Vane springs fail because of corrosive action; (3) Permanent pump ef ficiency is affected by corrosive deterioration of close mechanical tolerances.
How the Langdon Pump ends these problems • Contaminated oil can be quickly eliminated. T h e Langdon Pump employs a small volume (70 ml.) of inexpensive, easily-obtained (SAE 30) motor oil, which you can change in seconds while the pump is operating. • Spring failure is eliminated be cause the Langdon Pump has no springs. T h e Teflon vanes are seated, not by troublesome springs, but by a unique combination of hydraulic and centrifugal forces.
HEVI-DUTY
Single-stage, rotary, oil-sealed, watercooled, high-speed Langdon Vacuum Pump. Capacity: 35 1/min. (free air). Ultimate vacuum: 50 microns.
• Efficiency is essentially inde pendent of wear. Reason: the Langdon Pump employs relatively large clearances which are sealed by degassed oil films. These clear ances are also adjustable. • Cleaning is quick and easy. T h e Langdon Pump can be disassem bled, cleaned and reassembled in just 30 minutes by the average operator. Compare the Langdon Vacuum Pump point-by-point with other pumps. You'll agree that none match it for laboratory use. For information, write for liter ature or see the leading laboratory dealer in your area.
Dept. AC-5 Hevi-Duty Heating E q u i p m e n t Division
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Laboratory Furnaces, Ovens and Hot Plates
Circle No. 61 on Readers' Service Card 92 A
