1. QUALITY
Careful selection always pays in the end. Radial Lip seals are engineered to give optimum performance and long service life.
They are precision manufactured and subject to stringent quality control throughout all stages of production.
1. DESIGN
Operating conditions obviously affect the choice of seal. A wide range of special types is available but the following standard designs satisfy the majority of applications.
Open Seal - Type SC
Rubber-covered case. The most common and versatile type. The rubber-covered case provides effective protection against corrosion and good sealing round the housing bore.
Open Seal - Type SB
Metal case. Risk of damaging seal minimized, but fairly large force required when fitting.
Fully-Enclosed Seal - Type SA
Metal case. Very stable construction. Sealing member better protected than in open type. Particularly suitable for larger sizes.
3. FITTING
Correct fitting is of vital importance to the performance and life of a seal. A badly fitted seal can, moreover, cause damage to bearings and rotating parts, leading to costly downtime. Seal replacement should take place in as clean and dust-free surroundings as possible. The shaft should be thoroughly clean. Remove all burrs, sharp edges, uneveness and particles, and apply a thin coating of pure mineral oil. Keep the seal in its wrapping until just before use. Carefully smear the sealing lip with pure mineral oil. Take care to fit the seal at right angles to the shaft, while ensuring that the lip is not damaged. Remember the lip diameter is somewhat less than that of the shaft.
If the shaft has a square shoulder, a special sleeve should be used when fitting the seal. The diameter of the sleeve must be somewhat larger than the shaft's so that the seal can be eased over the edge without damaging the lip.
Use a bell tool or similar to distribute the load when pressing the seal into position.
If the seal is to be fitted with the open side outwards, a special tool may be required. Be careful with the sealing lip. It is sometimes necessary to remove the spring in order to position the seal properly.
4. LEAKAGE
Any appreciable leakage is very seldom the fault of the seal itself. It is most often the result of defects on the shaft or in the seal housing. It can also be due to the seal being of the wrong type or careless fitting. Try to trace the leak. If the leakage appears to come from the seal itself, carefully remove it and wipe it clean, and examine it.
