A COMPARISON OF THE OPERATING CHARACTERISTICS OF FLAT-FACE AND HYDRODYNAMICALLY LUBRICATED ROTATING MECHANICAL SHAFT SEALS IN HIGH PRESSURE WATER
Flat-face seals can be hydrostatically balanced to give low leakage rates and moderately low contact loads at the faces but the seal balance is extremely sensitive to changes in operation conditions. An increase in temperature or a decrease in pressure is followed by D large decrease in leakage, making it difficult to maintain a proper balance over a wide range of conditions. Excessive unbalance causes scuffing of the faces which leads to a greater unbalance and ultimately to failure. Taper-face seals however, develop a hydrodynamic film between the faces that adjusts to changes in pressure and temperature and can be designed to operate over a wider range oi conditions than the flat-face seals. They can be balanced so that the leak rate is almost independent of the system pressure and only slightly affected by a change in water temperature. On the other hand, the leak rate increases rapidly with speed and the balance must be adjusted to compensate for this. Starting is often difficult because the hydrodynamic film is not available to provide the proper balance, but this can be overcome. When the seals are properly balanced the friction torque of both flat-face and taper-face seals is less than 2 lb in. at 1900 rpm in water at 800lb/in/sup 2/. The results of numerous tests on both flat- face and taper-face seals operating under different conditions are presented in graphical form. (auth)
- Research Organization:
- Atomic Energy of Canada Ltd., Chalk River, Ont.
- NSA Number:
- NSA-16-031691
- OSTI ID:
- 4762485
- Report Number(s):
- CRE-1104; AECL-1588
- Resource Relation:
- Other Information: Orig. Receipt Date: 31-DEC-62
- Country of Publication:
- Canada
- Language:
- English
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