Abstract: The improved wellhead system includes a wellhead housing with an internal annular shoulder having a plurality of removed arcs to form an interrupted support shoulder. A casing hanger is provided with an external annular shoulder having a plurality of removed arcs which correspond with those on the wellhead housing. In a first orientation, the removed arcs of the casing hanger shoulder align with the arcs of the support shoulder in the wellhead housing to allow the casing hanger to pass through the wellhead housing or the wellhead housing to be lowered below the casing hanger. In a second orientation the remaining shoulder arcs of the casing hanger align with the support shoulder arcs to support the casing hanger. The casing hanger also includes a thread for attaching a tool whereby the casing hanger and casing attached thereto can be tensioned. An alternate embodiment of the improved wellhead system includes a wellhead housing with an internal support groove.

Abstract: Conveyor method and apparatus wherein there is provided a package carrying tray, a pair of endless control chains, a pair of endless load chains, and a motor and sprocket wheel-drive arrangement for rotating the chains in synchronism. The tray is so connected to points on the chains that the tray is maintained in substantially horizontal and vertical positions during portions of tray movement from and to package loading and unloading areas while compensating for changes in spacing between the points during movement from one position to the other. The connection involves providing a pair of pins each on an opposite side of one end of the tray, with each of the load chains secured to a pin at a point for pivotal movement. A pair of control arms are each secured to a pin at its end, and have a slide thereon which is fastened to a point on one of the control chains for pivotal movement. Fork assemblies, cooperable with the tray, provide for the loading and unloading of packages at designated stations.