From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
The features and principle of operation for Cone Type Hytor vacuum pumps and compressors.
| Identifier | ExFiles\Box 122\4\ scan0142 | |
| Date | 13th May 1938 guessed | |
| NASH ENGINEERING CO., (Great Britain) Ltd. In the Cone Type Hytor new standards for efficiency and range in a rotary vacuum pump or compressor have been established. These pumps reliably maintain vacuums up to 28 inches of mercury, and pressures up to 35 pounds per square inch. They show their best efficiency from 10 to 25 inches when used as vacuum pumps, and from 4 lbs. to 24 lbs. when employed as compressors. They can also be recommended for services above and below these limits in cases where absolute dependability is more important than a slight saving in horsepower, or on particularly severe services, such as the handling of dust-laden gases, or gases containing high percentages of liquids. These great efficiencies are obtainable only in the Cone Type Hytor, owing to numerous new features of pump design. The flow of air through the pump structure is as near as possible in a straight line. There are no abrupt changes in flow direction, and consequent air losses. Because of the cone construction there is no restriction of the inlet area of the rotor buckets, and it is therefore possible to design a rotor smaller in diameter, with higher rotating speed, a much smaller pump structure for a given capacity, with economies in space and horse power. The capacity and dimension tables on pages 7 and 8 should tell an engineer a very interesting story. The principle of operation of the pump is shown in the cuts on pages 4 and 5. A rotor (5) in hydraulic balance revolves freely without contact in an elliptical casing (6) (10) containing a liquid, usually water (4). This rotor (5) is a circular casting consisting of a series of blades (11) which project from a cylindrical hub to form pockets or chambers (13). Ports are arranged at the bottom of each chamber. A cone shaped casting (cut page 2) containing two inlet and two outlet ports as at (1) fits without contact into the rotor hub. Starting at point "A" the chambers are full of water. The water turning with the rotor and constrained to follow the casing (7) by centrifugal force alternately recedes from (4) and is forced back into the rotor (3) twice in a revolution. As the water recedes from the rotor (7) it draws air from the pump inlet into the cone, through the cone inlet port and into the rotor by means of the ports in the bottom of the rotor chambers. When the water is forced back into the rotor by the converging casing the air is discharged through the ports at the bottom of the rotor chambers, through the cone outlet ports and out the pump discharge. A small amount of seal water must constantly be supplied. Most of the water stays in the pump. Excess water is carried over with the air and is usually run to waste. In addition these pumps possess all the other unusual advantages that have been outstanding features of Hytor Vacuum Pumps and Compressors for many years. Diagram Labels: INLET PORT DISCHARGE PORT INLET DISCHARGE ROTATION IS CLOCKWISE Page Numbers: 4 5 | ||