Wear sleeves for heavy industrial applications (LDSLV4)
LDSLV4 wear sleeves are recommended for applications where operating conditions for the seals are difficult, particularly where solid contaminants can reach the seals, like in rolling mills, primary metal plants and in chemical and mineral plants.
The sleeves are made of SAE 1008 chromium-plated carbon steel to enhance wear and corrosion resistance. The sleeve outside diameter is specially ground to provide a precision counterface surface for the seal. The wall thickness of the standard sleeves is 2,39 mm (0.094 in.).
Using LDSLV4 wear sleeves
There are two alternative ways of using LDSLV4 wear sleeves (fig 2):
- The sleeve is positioned on the shaft until it covers the damaged part and a new seal, designed for a 4,78 mm (0.188 in.) larger shaft diameter, is used.
- The shaft is machined down by 4,78 mm (0.188 in.) in diameter, the sleeve is installed and the original seal size is used.
The reworked shaft surface for the sleeve should have a surface roughness between Ra 2,5 and 3,2 µm (100 to 125 µin.).
In applications where shaft damage and seal wear is expected, SKF recommends installing wear sleeves at the outset, i.e. before the application is operational. By doing so, whenever replacement is required, the original seal and sleeve sizes can be used and no reworking of the shaft is required.
The shaft tolerances for LDSLV4 wear sleeves, due to their heated slip-fit installation, are different from those for radial shaft seals. Contact SKF for assistance if the sleeves are to be used in systems with sustained temperatures higher than 75 °C (165 °F) and surface speeds in excess of 20 m/s (3 900 ft/min).
LDSLV4 wear sleeves are designed for a heated slip-fit installation and must therefore be uniformly heated prior to installation. The sleeve temperature should be approximately 180 °C (355 °F). Under no circumstances should the sleeve be heated to above 200 °C (390 °F). Any heating techniques normally used for bearings are suitable, such as induction heaters or heating cabinets.
The sleeves should be installed immediately after heating since they cool rapidly and could seize on the shaft before the correct position is achieved. If repositioning is necessary, use a soft faced hammer and a wooden block. After the sleeve is in the desired position, check the lead-in chamfer for any damage during installation.
LDSLV4 wear sleeves can be removed either by heating them or expanding them by light hammer blows.