Abstract: A process of positioning a riser sleeve about a plug of a mold cavity pattern. The riser sleeve is positioned to engage the plug to prevent sand from entering the interstitial space between the riser sleeve and the plug. The riser sleeve may comprise a deformable annular lip for engagement with the perimeter of the plug. The riser sleeve may engage the plug in sealing relationship.

Abstract: A pneumatic control apparatus and method controls gas pressure inside a tire (40) mounted on a wheel (32) which rotates about the centerline of an axle (30). A bleeder valve (28) is mounted on a body coaxially aligned with the axle centerline and is in fluid connection through passages (14, 18) in the billet and tubing (24) with a pneumatic fitting (23) on the tire. The bleeder valve allows gas inside the tire to be relieved to the atmosphere when the gas is above a set pressure. The coaxial alignment of the bleeder valve with the axle centerline permits the bleeder valve to relieve gas pressure unaffected by centrifugal forces.