英文翻译答案

英文原文

1. General description of the SIEMAG disc brake unit

This brake unit is the electro-hydraulic control system of a gearless disc brake for winders. The brake unit operates on the exhaust principle, i.e. the braking force is generated by sets of disc springs and released by hydraulic pressure.

The braking force generators with the brake shoes directly act axially on the brake disc. The braking force is generated by sets of disc springs and transmitted onto the brake shoes. The number of brake elements determines the respective braking force required.

As soon as the brakes are being released, the brake shoes are lifted form the brake disc with the aid of pressure oil. During the braking, the oil flows back into the tank and the brake shoes are being pressed against the brake disc.

The braking force generators type BSFG 408 are s series product supplied by the Swedish firm ASEA-Hagglunds. They have a maximum press-down force of2X7906 kN.

For reasons of better system availability, the hydraulic pressure is generated by two regulating pumps that are each driven by an electric motor. Both pumps are started when the system is being switched on. Any failure of a pump will be signaled.

The oil filtration is undertaken by a pressure filter‘6.2’provided in front of the braking force generators. Furthermore, two gear pumps that are directly coupled with the regulating pumps, maintain a permanent oil cooling and filtering circuit during system operation (filter‘6.1’and cooler ‘14’). Both filters have an electrical contamination control. The mesh size of the filters is specified by the supplier to be 10μm (see TAS No.3.9.6.4). The equipment includes a controlled electrical tank heating. The fluid level in the tank is monitored as well.

The service braking is done with the aid of two electrically controlled proportional pressure relief valves‘43.1’and‘43.2’that are hydraulically connected in series.

The safety braking is done with the aid of position-controlled 4/2-way electro valves‘53.1’、‘53.2’、‘39.1’、‘39.2’、‘58.1’、‘58.2’、‘66.1’，and‘66.2’which are electrically actuated in closed-circuit connection.

In the event of a safety braking, the directional control valves‘39.1’and‘39.2’are switched off, separating thus the pump pressure from the remaining brake releasing system(hydraulic shunt).

During the safety braking, the directional control valves‘6.1’and‘66.2’are acting as pilot valves for the 2/2-way valves‘65.1’and ‘65.2’which again release the pressure relief valves‘64.1’and‘64.2’.

The electro valves‘53.1’and‘53.2’operate as outlet valves according to TAS No.3.9.5.9.

The mechanically controlled pressure relief valves‘60.1’and‘60.2’are arranged in the outlet line of these valves. They determine the residual pressures in the course of safety braking. These residual pressures (pressure stages 1 and 2) are maintained by bladder-type accumulators.

The gas pressure of the respective accumulator used is monitored.

The march of pressure is adjusted with the aid of mechanical skids which are adapted to the braking process desired.

A hand-operated pump‘48’is provided for assembly purposes, when the controlled main stop cocks‘46.1’and‘46.2’in the outlet line of the brake elements are locked.