Heavy Machine

Heavy Machine: The Hydraulic Drive Truck Crane



Heavy Machine: The Hydraulic Drive Truck Crane

Hydraulic drive truck crane

The hydraulic drive truck crane is based on a simple concept -- the transmission of forces from point to point through a fluid. Most hydraulic machines use some sort of incompressible fluid, a fluid that is at its maximum density. Oil is the most commonly used incompressible fluid for hydraulic machines, including hydraulic cranes. In a simple hydraulic system, when a piston pushes down on the oil, the oil transmits all of the original force to another piston, which is driven up. In a simple hydraulic system, when one piston is pushed down, another piston is pushed up. A hydraulic pump creates the pressure that moves the pistons.

Hydraulic drive truck cranes operate with a single hydraulic pump (Fig-01). Speed control actuators combined: changing speed of the pump (due to changes in motor speed gear) and throttling the working fluid in the channels of control valves.

The motion of the box is transferred from the engine base car through its clutch, gearbox and driveshaft. Working fluid pipeline passes through a rotating joint on the rotary part of the crane and then to the hydraulic motors working mechanisms. This drive is called the multiengine with individual hydraulic working mechanisms. Hydraulic actuator in the tap-2571A COP-1 is made by open odnonasosnoy scheme. The flow of hydraulic fluid from the pump through dvuhpozi-tional control valve is directed to either the control valves, and through him to the hydraulic cylinders 2, 3, outriggers and lock mechanism spring or through a rotating joint (central collector) to the control valves (to drive the crane mechanisms). Flow control valve from the working fluid is sent to the cargo winch motors to the hydraulic cylinder boom mechanism for motors slewing platform. Hydraulic circuit (Fig. 01) allows the combination of the following business operations: lifting (lowering) with the rotation of the rotary arm of the ascent (descent) of cargo with the rotation of the rotary part.

Figure 01

1 - headroom Boom 2 - the boom, 3 - hydraulic cylinder telescopic boom, 4 - Cylinder boom, 5,8 - motors, 6 - reducer 7 - cargo winch, 9 - frame rotary, 10 - turning mechanism; 11 - geometrical axis of positioner, 12 - Pump 13 - PTO, 14 - transmission, 15 - engine. Combining operations is provided by a special section in the intermediate valves. ...