Abstract: A swivel assembly for interconnecting a pair of relatively displaceable conduits comprises a pair of outer swivel fittings each connected via a respective outer pipe to a respective one of the conduits, and a pair of inner pipes each connected between the other side of each of the outer swivels and a respective side of a single inner swivel. The outer side of each of the outer swivels is clamped fixedly on the respective conduit so that there is no strain in the outer pipe between each of the outer swivels and the respective conduit. To this end each such outer pipe may include a U-shaped section lying in a plane including the swivel axis of the respective swivel fitting and perpendicular to the axis of the respective conduit.

Abstract: A grate is formed of a plurality of grate elements each in turn having a horizontal elongated support tube extending above and parallel to a supply tube. One end of the supply tube is connected via an upright connector tube or the corresponding end of the support tube and a plurality of posts extend vertically down from the support tube to the supply tube with their lower ends connected to the support tube. One end of the supply tube is fixed and the rest of the supply tube can move relative to its fixed end so when a heat-exchange fluid is passed through the supply tube, connector tube, and support tube the supply and support tubes will expand or contract thermally and displace the upper and lower ends of the connector tube and posts to the same extent.

Abstract: An improved articulated pipe coupling for connecting a stationary pipe connection to a movable pipe connection is disclosed. The pipe coupling consists of two articulated pipes which are joined together and to the pipe connections by three interchangeable ball pipe joints. These pipe joints permit the articulated pipes to rotate relative to one another. The improvement to the pipe coupling consists of a resilient tension member connected between the uppermost pipe joint and the midpoint of the upper articulated Z-shaped pipe to apply a force to the upper pipe joint for all positions of the pipe coupling. This applied force has a component which acts on the upper pipe joint in a direction opposing the weight applied to the upper joint by the weight of the pipe coupling to relieve the weight loading thereon.