Transmitted torque

Various coupling designs are available to transmit torque from the driver, eg, electric motor, to a pump. In order to contain the pumped fluid inside the pump and prevent the pumpage from leaking, several types of sealing methods are used. A few options are described herein. 

Disk Coupling. Diaphragms are used to transmit torque between the iaside and outside diameters of the flexible element ia disk coupling (Fig. 14b). Up to 0.1-mm (0.004-ia.) parallel misalignment can usually be tolerated. Whereas no oil lubrication is required as compared to gear couplings, disks ate limited to moderate torques. 

An effective way of assembling a machine element such as a gear or pulley to a shaft is by shrink fitting. This involves setting up a radial pressure between a shaft with a slightly larger diameter than the inside diameter of the machine element, termed an interference fit. The part is heated to allow assembly and then on cooling the pressure on the inside diameter is established which maintains its ability to transmit torque from the shaft. 

Steady transmitted torque. Smooth nonfluctuating torque in electric motors, turbines, and a variety of smooth torque-absorbing load (driven) machines. 

Cyclically transmitted torque. Pulsating or cyclic torque in reciprocating prime movers and load machines such as reciprocating compressors, pumps, and marine propellers. 

There are three relevant bending moments caused by a gear coupling when transmitting torque with angular or parallel misalignment ... 

The torsionally soft or resilient coupling such as the quill shaft and the metal-metal resilient transmit torque can handle misalignment through springs, metal strips, coils, disks and diaphragms, They will tune the system by changing the spring constant K. 

Drivetrain efficiency depends on the rotational speed of individual components in the drivetrain and on the torque being transmitted. With a manual transmission, maximum drivetrain efficiency can be as high as 95 percent, but with an automatic transmission it falls closer to 85 percent. The pas-sciigcr-car transmission seldom runs at its maximum efficiency point, however. For both transmission types, drivetrain efficiency trends toward zero as the transmitted torque approaches zero. Note the following ... 

One-way A one-way or flywheel clutch is a device that transmits torque in one direction, but disengages in the opposite direction. The typical design of flywheel clutches incorporates a tooth profile that engages in one direction only. If rotation of the drive shaft is reversed, the drive hub will freewheel and cannot engage the driven hub. 

Positive intermittent power transmission, transmitting torque in one direction, disengaging in the opposite direction... 

E.3.4.2 An overrunning clutch (that is, a clutch that transmits torque in one direction and freewheels in the other) should generally be used between the HPRT and the train to allow the driven equipment to operate during HPRT maintenance and to permit start-up of the train before the HPRT process stream is hned up. 

C.3.4.3 An overrunning clutch (that is, a clutch that transmits torque in one direction and freewheels in the... 

Figure 274(a) depicts the drive system which was already part of the earliest machines (see Figure 225). More recent machines, instead of powering shaft (3) by transmission belts, apply a motor (5) with a torque-limiting clutch, a gear reducer (4), and a flexible coupling to drive gear shaft (3) mounted in or on the roller press frame. The gear on shaft (3) transmits torque to the coupled gears (2) on the roll shafts between two roller bodies (1).

Select a suitable factor for the pull-out torque Afp, (Afp, = 1.5 A/ for light duty and 2.5 Af for severe duty). If the blade runs into a solid obstruction it will experience a stalling side load at a point three quarters along the length of a blade. The transmitted torque increases from M, to Afp, and ... 

In some applications, torsion is applied to a press-fit assembly. Transmitted torque M is calculated by [6]... 

From Eq. 8.1, it can be seen that the transmitted torque is directly proportional to the horsepower and inversely proportional to the screw speed. The power to the screw is related to the motor power by ... 

The major function of a sprocket is to transmit torque. So, the main considerations in designing a sprocket tooth form are as follows. 

The ability of the sprocket to transmit torque largely depends on the tooth pressure angle. Note that there is no equation for pressure angle given in Figure 4-36. Values for pressure angles are given in ASME B29.10. 

In order to allow movement, we will have another question to answer will we transmit torque to wheels or will we use a water flow to provide propulsion Evenifthe second option was adopted, we still would need wheels and, even more importantly, we would need abigger pump. The biggest problem is that the equipment will not run if the... 

At this point, there is an interesting question to approach how do we transmit torque from the engine to the wheels Although this does not seem to be a problem, we must remember that each wheel will go a different distance when the equipment changes its direction. Therefore, there are two common ways to do this. 

Another design of a three-lobe bearing has three equal-diameter bores that are displaced 120° from each other by an amoimt equal to the bearing clearance less the oil-film thickness. This bearing is center-fed. It is used to support lightly loaded shafts, especially light gear shafts in which the load direction varies with the transmitted torque. 

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