Small Packless Valve

A 35/20 male spherical joint is heated 10 mm. from the ground. «edge and a ridge formed ... 15,521A as lubricant on the ground-glass surfaces, six of...
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Figure P (Left and Above). Component Parts and Completed Oil-Sealed Spherical Joint

SECTION A-A

A 35/20 male spherical joint is heated 10 mm. from the ground edge and a ridge formed which will equal the 28-mm. hole in the large tube. The male joint is then inserted into the large tube and the two pieces are fused together. The oil-retaining cup is placed on the male joint rather than on the female joint to allow disassembling without the necessity of removing the oil.

Small

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Vol. 17, No. 11

INDUSTRIAL A N D ENGINEERING CHEMISTRY

742

Dimensions and constructional details are shown in Figure 1, and the component parts and the completed assembled joints are shown in Figure 2. Any size of joint may be used if proportionate changes in dimensions are made. Using Apieaon oil J for the oil seal and Cenco grease No. 15,5218 as lubricant on the ground-glms surfaces, six of these oilsealed spherical joints are being used satisfactorily to obtain lo-' Pressure in the large high-vacuum system at mm* of Armour Research Foundation.

Packless

T IS frequently necessary to manipulate pure gases under con-

ditions where glass stopcocks cannot be used. One such instance is the transfer of pure gas from a small pressure container to a vacuum system where leakage cannot be tolerated. Ordinary packed valves of the Hoke type are not suitable for this service because of contamination resulting Prom the ptcking as well as leakage under vacuum. Furthermore, packless valves available at present on the market are much too bulky to be fitted to the small pressure containers it is frequently desirable to use. Consequently a small packless valve which is readily fabricated in any machine shop was devised. The body of the valve is a l/&nch brass Hoke body with the internal stem threads drilled out to take a 6/I6-inch copper bellows. The bellows is soldered to the lower portion of the stem and to the upper portion of the body, providing a vacuum- and pressure-tight seal of both sides of the valve. The diameter of the flange on the needle is fixed by the size of the collar on the bellows into which the flange fits snugly before soldering. No difficulty with seating of the needle has been experienced, and because of the small movement of the aeedle relative to the seat, no appreciable wear due to rubbing of the bellows on the side walls is to be expected nor has any been found, The diagram shows the constructional details. This valve has already been used for the service described and has proved completely satisfactory.

Valve

W. S. YOUNG, The Atlantic Refining Co., Philadelphia, Pa. 3

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ACKNOWLEDGMENT

Acknowledgment is made to R. G. Simard for his part in the final design and testing of this device.

a $ l c 0.0. I . 0ELlOWS -TYPE

a K H 4 Y E VALVE

BODY

CLIFFOKD MFC. CO.

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