Linear Bearings Let Mobile Hospital Expand

The 53-ft-long mobile hospital unit designed by the Special Vehicles Co., Pfafftown, N.C. needed more space than the tractor trailer on which it was mounted would allow. So the company planned to add a 3 × 10-ft slide-out that would hold up to 2,000 lb of cabinets, refrigerators, and analysis equipment. Although the company usually uses hydraulics to support slide-outs and help them move easily, this approach would have been expensive and would have compromised the structural stiffness of the trailer and unit. Designers instead employed compact-rail linear bearings from Rollon Corp., Sparta, N.J., because of their cost, ease of installation that would not effect stiffness, and the bearings’ ability to handle positioning errors and misalignments. The bearings also have raceways on the inside of their rails which protect them from damage and contaminants. Three six-roller slides were installed and proved more than capable of handling the 2,000-lb weight.