Loading high torque

Torque the rotating force developed by a motor for starting and carrying loads. Some loads require high torque motors. 

The tool features a spline assembly that transmits high torque loads to the bit through its outer tube, while the inner assembly absorbs vibration through a series of steel-disc springs. The spring system works in both suspension and compression. 

DC motor drives have always offered high torque at all speeds and exact control of motion speed. AC induction motors have reliably converted electricity into rotary power for many years, and recently adjustable-frequency controls add variable-speed capability. While AC motors were originally relegated to relatively simple tasks, such as varying the flow rates of fans or pumps, advances in both motor and control technologies have allowed their use in higher performance operations. They are reliable sources of fixed-speed and variable-speed rotating power. Electric drives with appropriate closed-loop control operate only when required. However, to avoid unsuccessful apphca-tions, it is important to properly match the load, motor, and controller. 

McCarthy CT, Gray PJ. An analytical model for the prediction of load distribution in highly torqued multi-bolt composite joints. Compos Struct 2011 92(2) 287—98. 

High-torque motors—for heavy loads with high inertia. 

Provide motors of optimum horsepower and torque if viscous fluids are to be handled, since high torque is required for operating at heavy starting loads (e.g. cmshers/grinders). 

Figure 2.23 The bolt tension generates friction which is manifest in the torque required to remove the nut (Figure 2.22). This is additional to the combined effects of adhesion and crushing load induced by anaerobic adhesives (Figure 2.21). Here, with the two sets of curves combined, it may be seen that very high torques can be required to initiate movement.

Single-rotor and twin-rotor hammer crushers are usually driven by slip-ring motors via a V-belt transmission system. As a rule, slip resistors are provided in order to ensure flexible behaviour of the drive motor. In the event of a drop in rotation speed due to impact loading of the rotor, the motor will still develop a high torque and the V-belt drive will be less severely strained. The drive pulley, which serves as a flywheel, is overhung-mounted on the rotor shaft - even on the largest crushers hitherto built - and is fixed by means of locking sleeves or similar devices. 

C Double-cage, high-torque Ball mill, loaded reciprocating compressor, large conveyor, hammer mill, high-viscosity liquid mixer, kneader, rotary kiln. 

Current-ramp units can be applied on variable-torqne, some constant-torqne, and high-inertia loads. They are not recommended for loads that vary considerably since they may not be able to start the load sometimes. As with any type of rednced-cnrrent or soft-starting means, it is necessary to evalnate high-starting-torqne appUcations to determine feasibihty. Some loads demand such high torque at locked rotor that any kind of rednced cnrrent will not allow the motor to start. 

Flexible shaft or spring couplings are generally used in small equipment applications that do not experience high torque loads. Figure 11.8 illustrates a typical flexible shaft coupling. 

Small equipment that does not experience high torque loads Torsional stiffness while allowing flexibility in axial movement Light- or medium-duty applications running at moderate speeds Gradual acceleration and limited maximum torque for flxed operating speeds (e.g., compressors)... 

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