measure the rotary table torque and is applicable to a mechanical rig without set screws and with the rotary table

The sensor is used to measure the rotary table torque and is applicable to a mechanical rig without set screws and with the rotary table driven by a chain case. 

During drilling, the diesel motor drives the drawworks and rotary table through a series of driving devices and then the driving chain, and the rotary table drives the drill string to realize drilling. The tension degree of the driving chain can be corresponding with the table torque. When the downhole drill string is out of order or the formation lithology is changed, the table torque will change, thus affecting the variation of the chain tension force. Based on this principle, place a tension pulley type table torque sensor below the driving chain. The sensor converts the chain tension force into oil pressure, and then a pressure sensor converts the outputted oil pressure signals into electric signals. The electric signal intensity reflects variation of the table drive torque and makes for timely knowing downhole conditions. 

See the following Figure for the system composition of the SK-8N02 tension pulley type table torque sensor. The system includes: (1) SK-8Y21A pressure sensor (6Mpa), (2) high pressure hose, (3) tee quick coupler, (4) base plate, (5) spacing bolt, (6) high pressure oil cylinder,  

(7) suspension, (8) tension pulley, (9) adjusting screw, (10) short foot plate, (11) long foot plate and (12) oil injection quick coupler etc. In order to be convenient for injecting pressure oil, a quick coupler is used to connect the pressure sensor with the high pressure hose of the tension pulley type table torque sensor to make for assembly and disassembly.

Mounting position: the tension pulley type table torque sensor has two mounting modes for different rigs; however, for both mounting modes, the sensor is mounted at the tension side of the stressed driving chain.

SK-8N02 Tension Pulley Type Table Torque Sensor