New Concepts in Scientific Glassware
NEW PRODUCTS
HIGH NEW! CAPACITY! TWO-STAGE WELCH "DUO-SEAL" VACUUMPUMPNo.1398 50 CFM (1400 UTERS/MINUTE)
Unique new 0-RING joints are grease-free Delmar's new O-Ring joints provide positive sealing with a groove and several pressure ridges which engage a ring of Buna-N or Viton-A, a new fluorine elastomer resistant to many petrochemicals and silicate esters. Features include : • • • •
Leakproof joints Xo contamination Fast assembly—no greasing Yiton O-Rings hold pressures down to l(P 6 rmn, in tempera tures from — 4I)°F to +50(I°F.
Components
Three new components-diffusion p u m p , water-cooled chevron ring baffle, and sorbent t r a p - c a n be assembled quickly into a complete ultra-high-vac uum pumping system. Pressures in the region of Ι Ο 9 to Ι Ο 1 0 T o r r are attainable. T h e m a t c h e d sets of stain less steel components are available in 2, 4, 6, and 10 inches to permit choice of pumping speed and through p u t . Applications include gas particle behavior studies, electron microscopy, and environmental simulation. Con solidated Vacuum C o r p . 433
The Delmar-l'rry needle valve has a glass body and glass stems. I t can be used wherever a greased stopcock of the usual type is utilized. Fitted in the body is a stem fabricated of Teflon, grooved and fitted with (Vi ton-A) O-Rings usable for pressures from Κ Γ Ί Ι Ι Γ Ι , in temperatures from - 4 0 ° F to +5()0°F. Available in sizes for 0-4nmi and 0-10mm. Price $10.00 each.
Delmar SCIENTIFIC LABORATORIES 317 MADISON ST., MAYWOOD, ILL A SUBSIDIARY OF COLEMAN INSTRUMENTS, INC. Circle No. 136 on Readers' Service Card
T H E YOUNGEST, BUT LARGEST MEMBER of the Welchfamily of "Duo-Seal" oil sealed rotary vacuum pumps makes its appearance as the No. 1398. This new pump offers very high capacity and ex cellent ultimate vacuum characteristics with no sacrifice of long life, low mainte nance, freedom from vibration and mini mum noise level. These features have long made Welch "Duo-Seal" pumps the most widely used of all rotary vacuum pumps. 1398's, like all Welch "Duo-Seal" Pumps, are thoroughly run-in at the factory and tested until they exceed their vacuum guarantee. The new 1398 is highly recommended for all industrial and laboratory applications requiring high pumping capacities and low pressures. Typical uses are electron tube evacuation, vacuum distillation, de hydration, reduction, sublimation, metal lizing, metal processing, leak detection, hermetic sealing and back-filling, impreg nation and general scientific studies. IMPORTANT FEATURES: • High pumping speed — 50 CFM (1400 liters/minute) • Low ultimate pressure — 1 χ 10-< mm Hg (McLeod) • Quiet, vibration-free operation • Compact, rugged design • Air-cooled • Vented Exhaust Valve • Flanged, O-Ring-Sealed Intake Port • Totally Enclosed Belt Guard • Air Intake Screen • Exhaust Filter
New! Greaseless Hi-Vacuum Stopcock
For full details on these new Delmar items, ask for Catalog 61-MA
1 χ 10-» mm Hg (tu MICRONS;
Environmental chamber which is dust and vibration free has remote re frigeration. Temperature range is - 1 2 5 ° to + 3 5 0 ° F. Inside dimen sions are 1 5 " χ 1 5 " χ 1 5 " . There is forced-air circulation within the chamber. Temperatures are pro grammed, recorded, and controlled. Model WT-2-125+350. Webber Manufacturing Co., Inc. 432 U l t r a High Vacuum
:
• T r o u b l e - f r e e , low m a i n t e n a n c e WELCH "DUO-SEAl" PUMPS ARE CARRIED IN STOCK BY AUTHORIZED DEALERS ;
Hydrogen generator eliminates need for hydrogen tanks and incorporates " f a i l - s a f e " feature. Hydrogen flow is variable from 0 to 4 0 m l . / m i n . and air flow rate is constant at 3 0 0 ml./min. Aerograph Model A-650. Wilkens Instrument & Research, Inc. 434
Welch Duo-Seal Vacuum Pumps are manufactured in wide variety of capac ities and ultimate vacuum character istics. They range in capacities from 21 to 1400 liters/minute and ultimates4 from 2 χ 10-' mm Hg down to 1 χ 10 mm Hg. WRITE FOR DUO-SEAL CATALOG and BULLETIN 1398 for full description and prices.
SINCE 11880 I
THE WELCH SCIENTIFIC CO. foremost manufacturera of scientific equipment
1521'Sedgwick St. ·
Chicago 10,111.
Circle No. 109 on Readers' Service Card
VOL 34, NO. 3, MARCH 1962
•
137 A
