Motors hydraulic

A mud motor (Fig. 3.17) is a positive displacement hydraulic motor, driven by the circulated drilling fluid. A continuous seal is formed between the body ( stator ) and the... 

The principle of operation of the hydraulic reciprocating pump is similar to the beam pump, with a piston-like sub-surface pump action. The energy to drive the pump, however, is delivered through a hydraulic medium, the power fluid, commonly oil or water. The power fluid drives a downhole hydraulic motor which in turn drives the pump. A separate surface pump delivers the hydraulic power. The power fluid system can be of the closed loop or of the open type. In the latter case, the power fluids are mixed with the produced fluid stream. The performance of the hydraulic pump is primarily monitored by measuring the discharge pressures of both surface and sub-surface pumps. 

Why do we use the word driver We tend to think that pumps are powered by r-r motors. However, some pumps are powered by internal combustion engines, or with turbines or hydraulic motors. Not always are pumps and drivers connected h a direct coupling. Some pumps are coupled through pulleys, chain drives, gearboxes or even transmissions. 

The bearing of top and bottom driven filters, that supports the rotating plate stack and its sealing, is complex since it has to withstand the internal pressure and the side forces imposed by the mechanical drive. However, side loads on some machines are eliminated by the use of hydraulic motors. 

The energy within a hydraulic system is of no value until it is converted into work. Typically, this is accomplished by using an actuating device of some type. This actuating device may be a cylinder, which converts the hydraulic energy into linear mechanical force a hydraulic motor, that converts energy into rotational force or a variety of other actuators designed to provide specific work functions. 

An actuator is a device that converts fluid power into mechanical force and motion. Cylinders, hydraulic motors, and turbines are the most common types of actuating devices used in fluid power systems. This chapter describes various types of actuating devices and their applications. 

Dual drive magnetic clutch Two or four cylinder open compressor Hydraulic motor... 

Power, Energy, and Drives. Centrifuges accomplish their function by subjecting fluids and solids to centrifugal fields produced by rotation. Electric motors are the drive device most frequently used however, hydraulic motors, internal combustion engines, and steam or air turbines are also used. One power equation applies to all types of centrifuges and drive devices. 

An injection molding machine is operated by hydraulic power and equipped with an dectric motor and hydraulic pump. The maximum hydraulic oil pressure is ca 14 MPa (2000 psi). A hydraulic cylinder opens and closes the mold and holds the mold dosed during injection another cylinder forces the screw forward, thereby injecting the mdt into the mold. A separate hydraulic motor turns the screw to plasticate, homogenize, and pressurize the mdt. Control of these movements is a combined function of the hydraulic and electrical systems (35—37). 

Fig. 13. Injection mol fling machine A, hydraulic motor for turning the screw B, hydraulic cylinder and piston allowing the screw to reciprocate about three diameters C, hopper D, injection cylinder (a single-screw extruder) E, nozzle F, fixed platen G, tie rods H, mold I, movable platen J, hydraulic cylinder and piston used to move the movable platen and supply the force needed to keep the mold closed and K, machine base.

As the removed solids begin to build up on the mesh screen, the pressure differential increases until, at typically 7 to 8 psi, a solenoid-actuated rinse valve is opened, allowing some of the water to flow to drain. The sudden reduction in pressure within the rinse area and the lower chamber, caused by the rinse valve opening, permits an internal hydraulic motor (containing top dirt collection nozzles and bottom rotary nozzles) to spin. 

As the hydraulic motor turns, a back-flush stream resulting from the reduced pressure sucks dirt from the mesh screen and through the motor s collection nozzles. The combined dirt stream and rinse water are ejected from the motor s rotary nozzles, scouring the entire screen surface and removing all traces of dirt. The rinse cycle is automatic, occurring at time intervals relative to the dirt content of the water. Each cycle takes only a few seconds and does not interrupt normal water flow. 

The metering b.in has a capacity of 1.6 m3 and has a live bottom discharge. A hydraulic motor drives the drag chain conveyor. A hydraulic power unit equipped with an electrically driven pump, flow regulator valve, pressure relief valve, and solenoid valve control the flow and pressure of hydraulic fluid... 

The rate of addition of solid fuel is controlled from the metering bin. A hydraulic system drives the metering bin conveyor. When the metering bin conveyor is stationary the electrically driven pump on the hydraulic power unit recirculates the hydraulic fluid to the reservoir. To start the metering bin conveyor a solenoid valve is opened allowing hydraulic fluid to turn the hydraulic motor. The flow and pressure of fluid to the hydraulic motor and ultimately the conveyor speed is controlled by a 12 position regulator valve on the hydraulic power unit. 

Rotational speeds are very low, in most cases ranging between 50 and 200 RPM. The low-speed hydraulic motors develop very high torques on the shafts, providing considerable shearing power to the cutting discs. This power makes shear shredders effective in difificult-to-cut materials. This equipment has been used to shred materials such as metals, truck and car tires, wood, pallets, bulky objects, and electrical and electronic devices, for example, in relatively coarse particle size. On the contrary, they are not capable of shredding materials into fine size (less than 10 mm). The main advantage of shear shredders is that... 

Other developments have not been as dramatic, but they have nevertheless contributed significantly to the process efficiency. The electric screw drives were replaced by hydraulic motors with a gear box on the reciprocating screw unit. In the future the hydraulic motor may in turn be replaced by a direct hydraulic drive (19). The Introduction of stack molds has also increased productivity. In a stack mold, two cavity plates are placed on top of each other so that the projected area is the same and twice as many parts can be formed with the same clamping tonnage. This technique works best with thin wall, flat parts with short cycle times. 

The operation of the injection and clamp units and other components of the injection molding machine (opening and closing of the mold and melting and injection of the polymer material) requires power, which is supplied by an electric motor. The orderly delivery of this power depends on auxiliary systems the hydraulic and control systems. The hydraulic system, the muscle for most maehines, transmits and controls the power from the electric motor to the various parts of the maehine. Maehine functions are regulated by a careful control of the flow, direction, and pressure of the hydraulic fluid. The elements of the hydraulic system for most injection molding machines are essentially the same fluid reservoir, pumps, valves, cylinders, hydraulic motors, and lines (Figure 11.8). 

Having determined the power requirement of the agitator, the next problem is that of designing a suitable method of transmitting this power from the electric or hydraulic motor. 

The hydraulic motor drive was a piston-type, nine-cylinder, fixed-stroke imit and provided a rated 40 hp at 6000 rpm with 25-gpm oil at 3000 psi. This accommodated a high-output pump performance of 100 psi shutoff head at 8500 rpm, and 1510 gpm at... 

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