VII. Translate the following sentences paying attention to Participle II.

1. A crane bridge is a latticed truss (ферма) supported by wheels.

2. Several jacks operated by one electrically driven pump are jointed together to raise structures weighing thousands of tons.

3. The fluid is forced into the cylinder from chamber by pump actuated by a lever.

4. Self-powered jib cranes can load materials excavated in small quarries.

5. For load handling the crane is operated by the motor mounted on the turntable.

6. Crawler and air-tyred cranes are driven by an engine mounted on the turntable.

7. Elevators are equipped with winches designed on the same lines as electrically driven cranes and construction winches.

VIII. Read and translate the following text.

LOADING EQUIPMENT

There are different types of loaders. They are classified as follows:

a) by the purpose: for handling piece and loose loads;

b) by the character of working process: for intermittent operation – single –bucket, for continuous operation – multi-bucket;

c) by the running gear: crawler and air-tyred;

d) by the kind of engine: with electric motors powered from the mains, with an internal combustion engine and with a diesel electric multi-motor drive.

S i n g l e - b u c k e t l o a d e r s

Single-bucket loaders can be subdivided into front loaders, swing loaders, rear loaders, and combination types. In front loaders the bucket is tilted forward. In swing loaders the bucket is swung sideways to be dumped. Front and swing loaders are provided with changeable equipment for maintaining various loose and piece loads (large and small buckets, grabs, forks, hooks, etc). Modern types of loaders have a hydraulic system for raising and lowering the bucket.

M u l t i - b u c k e t l o a d e r s

Multi-bucket loaders are available in chain and rotary types.

A crawler-mounted multi-bucket loader is employed for transferring sand, gravel, crushed stone, slag and other loose materials from stockpiles onto trucks. It can scoop the material in a quarry directly at the face, although it cannot operate on compacted and frozen loose materials. Multi-bucket loaders with a rotary operating member are also used for continuous service.

As compared with chain-type loaders, multi-bucket loaders have fewer but larger buckets. These buckets are arranged over the circumference of the rotor. As the rotor revolves the buckets become filled and going up dump the material onto a belt conveyor. The rotor is made in the form of a spherical head. The spherical head carries six buckets of the rotor. The rotor with the buckets is rotated around the carrying tube by an electric motor through a reduction gear, a shaft and a toothing. The buckets scoop the material, go up and discharge it onto the receiving belt conveyor located in the tube. The receiving conveyor delivers the material through the hopper onto the cantilever conveyor which discharges the load onto trucks. It should be noted that the cantilever conveyor can swing in a horizontal plane through 72 degrees both ways from the center line.