Most rubber belt shrinking machines have the internal water spray installed in the wrong location. The internal water spray is used to lubricate the belt interior. Lubrication is important so that as the rubber belt elongates and becomes wider as it is squeezed at the nip point, it must slip easily against the surface of the pressure roll, otherwise elongation of the belt will be restrained and the capacity of the rubber belt to recoil and compact the cloth will be reduced. Severe abrasion to the rubber belt interior may also occur.

Therefore, the internal water spray should be located just below the pressure roll and after the water removal roll. Water sprays located at the back side of the rubber belt are very much less effective, since most water applied to the belt inner surface at this location, will be removed by the wiping action of the belt idler roll and the water removal roll (s), by the time it arrives at the pressure roll.