Abstract: A safety interlock valve with two flow passages, which in one position allows flow through the flow passages and blocks flow between them, and in another position blocks flow through the flow passages and allows flow between them. The safety interlock valve can be used in hydraulic systems such as power tongs.

Abstract: A power tong is provided for rotating a pipe, the power tong comprising: a frame having a pair of arcuate front portions defining a throat for receiving the pipe; a ring gear mounted for rotation on the arcuate front portions about a center of rotation, the ring gear having an opening that is alignable with the throat; and a cage plate assembly mounted for rotation on the ring gear on a bearing arrangement that includes roller bearings and a bushing sliding segment on each side of the throat. Taking the throat as having a center line that defines a zero circumferential position within the power tong, the bearing sliding segments may be located within 90 degrees of the throat center line.

Abstract: A power tong for rotating a pipe, the power tong comprising: a frame having a pair of arcuate front portions defining a throat for receiving the pipe; a cage plate assembly mounted for rotation on the arcuate front portions about a center of rotation, the cage plate assembly having an opening that is alignable with the throat; a ring gear mounted for rotation within, and supported by, the cage plate assembly about the center of rotation, the ring gear having an opening that is alignable with the throat; the ring gear cooperating with jaws mounted on the cage plate assembly for gripping the pipe upon rotation of the ring gear.

Abstract: A safety interlock valve with two flow passages, which in one position allows flow through the flow passages and blocks flow between them, and in another position blocks flow through the flow passages and allows flow between them. The safety interlock valve can be used in hydraulic systems such as power tongs.

Abstract: A tong assembly is disclosed, comprising: a frame having at least a pair of posts spaced laterally from each other to receive a tong between the posts, each post extending vertically and having a lateral stabilizing surface on a side facing inward or outward; and a tong stabilized in relation to the frame by the lateral stabilizing surfaces and by each post being received by respective openings in the tong that have a cross lateral dimension sufficient to permit cross lateral movement of the tong in relation to the frame by at least one half of the cross lateral length of the lateral stabilizing surface.

Abstract: An apparatus for shutting off the hydraulic supply of a power tong when the door is opened comprises, in part, a ring gear and cage assembly having a throat. The ring gear and cage assembly are driven by a motor having a hydraulic supply. A door is mounted on a pivot on the ring gear and cage assembly for movement to open and close the throat. A cable is secured to the door at a point that is offset from the pivot. The cable extends through a sleeve to a valve end of the cable. A valve at the valve end of the cable has a valve housing and is operable by movement of a valve control to disengage the hydraulic supply from the motor. The valve end of the cable is connected to the valve control and the sleeve is connected to the valve housing.

Abstract: A power tong for rotating a pipe, the power tong comprising: a frame having a pair of arcuate front portions defining a throat for receiving the pipe; a cage plate assembly mounted for rotation on the arcuate front portions about a center of rotation, the cage plate assembly having an opening that is alignable with the throat; a ring gear mounted for rotation within, and supported by, the cage plate assembly about the center of rotation, the ring gear having an opening that is alignable with the throat; the ring gear cooperating with jaws mounted on the cage plate assembly for gripping the pipe upon rotation of the ring gear.

Abstract: A power tong with a cable operated door jammer valve for shutting off the hydraulic supply of a power tong when the door is opened.

Abstract: A rotor for a crushing machine has a central block mounted on a shaft for rotation. The central block has tapered blade mounting faces circumferentially spaced about the central block. A blade is secured to each tapered blade mounting face. Each blade has a tapered rotor mounting face matching the tapered blade mounting face. Each blade is secured to the rotor by a pin to pull the tapered rotor mounting face of the corresponding blade against a corresponding tapered blade mounting face of the rotor and lock the corresponding blade onto the rotor by frictional locking of the tapered blade mounting face and the tapered rotor mounting face. Each blade preferably has a square impact face with four cutting edges and the tapered blade. mounting face. and tapered rotor mounting face match in four rotational positions so that each blade is rotatable to place any one of its four cutting edges on the outer periphery of the rotor.

Abstract: A tubing spider includes a rigid support frame having a plurality of support posts and an upper and lower support ring separated by said support posts, a pyramidal frustum formed by a plurality of inclined planes rigidly attached to the support frame, a plurality of slips moveable along the inclined planes and hydraulic cylinders for actuating the slips. The pyramidal frustum and the range of travel of the slips extends substantially the entire length of the support frame between the upper and lower support rings. These slips define a cylindrical opening, the diameter of which changes as the slips move along the range of travel. In one embodiment, the support frame may be opened up as the upper and lower support rings are comprised of two hemispherical halves which are joined together in a hinged manner.

Abstract: A power tong system, comprising a frame having a rear support and a front support, the front support comprising a first front leg and a second front leg; and a power tong mounted in the frame with the power tong extending transversely between the first front leg and the second front leg, the first front leg and the second front leg forming a guide preventing transverse motion of the power tong while allowing vertical movement of the power tong. The system is also preferably provided with a backup tong. The sides of the power tong are preferably provided with rollers to prevent friction between the power tong and the guide. In a second power tong system, a load cell assembly is provided in which a load cell is linked by a series of links to the power tong such that movement by the power tong in either of two transverse directions loads the load cell.