Abstract: A pulley for a transmission system, including a central rotatable hub having a circumference; and a plurality of adjoining identical pulley segments rotatably mounted about the central hub circumference, wherein the adjoining pulley segments form an approximately circular stepped pulley shape and each of the pulley segments includes two sections providing two curved shelf surfaces for engaging a flexible drive member, each shelf having a different radius, forming higher and lower steps, and further wherein each of the pulley segments are independently rotatable about a radial axis with respect to the central hub.

Abstract: A pulley for a transmission system, including a central rotatable hub having a circumference; and a plurality of adjoining identical pulley segments rotatably mounted about the central hub circumference, wherein the adjoining pulley segments form an approximately circular stepped pulley shape and each of the pulley segments includes two sections providing two curved shelf surfaces for engaging a flexible drive member, each shelf having a different radius, forming higher and lower steps, and further wherein each of the pulley segments are independently rotatable about a radial axis with respect to the central hub.

Abstract: A drill pipe identification system automatically provides an identification number for each drill pipe as the drill pipe is being lowered into or withdrawn from the well. The system has a SAW identification device which is mounted in a cylindrical cavity which is formed within a tool joint of each section of drill pipe. The cavity has an aperture leading to the exterior of the tool joint to allow radio frequency signals to be received and reradiated. The SAW device receives signals from a transmitter and receiver, modulates the signals and reradiates them in a manner that corresponds to an encoded number in the SAW device.