1) Mark these statements t or f according to the information in the text:

1. Antilock braking systems were available in 1988.

2. Usually discs are mounted on the four wheels.

3. Front and rear hydraulic circuits are separated.

4. Pistons push the brake shoes against the inner surface of the brake drum attached to the wheel.

5. Mechanical brakes were difficult to keep adjusted so that equal braking force was applied at each wheel.

2) Match heads and tails:

ABS installations consist of	because of their fade resistance.
Disc brakes have become increasingly popular	by hydraulic systems.
Further increases in vehicle weights and speeds in the 1950s made even hydraulic brakes difficult	between the movable ends of the brake shoes.
Mechanical brakes were replaced	for drivers to operate effectively.
The wheel cylinders are located	wheel-mounted sensors.

3) Match these terms with their definitions:

1. brake shoe	A. a long curved block, typically one of a pair, which presses on to the drum in a drum brake
2. drum brake	B. a type of vehicle brake in which brake shoes press against the inside of a drum on the wheel
3. hydraulic system	C. when the brake pedal is connected to pistons in master cylinders
4. ABS	D. wheel-mounted sensors that input wheel rotation speed into a microprocessor
5. disk brake	E. a type of vehicle brake employing the friction of pads against a disc that is attached to the wheel

4) Fill in the gaps:

Until the 1930s, most systems for stopping __1__were mechanically actuated __2__with internally expanding shoes; i.e., foot pressure exerted on the __3__was carried directly to semicircular brake shoes by a system of __4__. Mechanical brakes, however, were difficult to keep adjusted so that equal braking force was applied at each wheel; and, as vehicle weights and speeds increased, more and more effort on the brake pedal was demanded of __5___.

1. drum brakes

2. brake pedal

3. flexible cables

4. the driver

5. vehicles

Құрастырушы

Оқытушы _________________________ Жамалиева А.А.

(қолы)

«Шет тілдері» кафедрасының отырысында қарастырылған және бекітілген.

Хаттама № _ ________________ ж.

Д.СЕРІКБАЕВ атындағы ШЫҒЫС ҚАЗАҚСТАН МЕМЛЕКЕТТІК

ТЕХНИКАЛЫҚ УНИВЕРСИТЕТІ

Ақпараттық технологиялар және энергетика факультеті

Шет тілдер кафедрасы

БЕКІТЕМІН

каф.меңгерушісі

­­­­­________Сарсембаева А.А

_____________________ж.

Heavy equipment

Heavy equipment refers to heavy-duty vehicles, specially designed for executing construction tasks, most frequently ones involving earthwork operations. They are also known as, construction equipment, construction plant, earth movers, engineering vehicles, or simply equipment.

They usually comprise five equipment systems: implement, traction, structure, power train, control and information. Heavy equipment functions through the mechanical advantage of a simple machine, the ratio between input force applied and force exerted is multiplied. Currently most equipment use hydraulic machinery as a primary source of transmission.

Until the 19th century and into the early 20th century heavy machines were drawn under human or animal power. With the advent of portable steam-powered engines the drawn machine precursors were reconfigured with the new engines, such as the combine harvester.

The design of a core tractor evolved around the new steam power source into a new machine core traction engine, that can be configured as the steam tractor and the steamroller. During the 20th century, internal-combustion engines became the major power source of heavy equipment. Kerosene, ethanol and gasoline engines were used, but today diesel engines are dominant. Mechanical transmission was in many cases replaced by hydraulic machinery. The early 20th century also saw new electric-powered machines such as the forklift. Caterpillar Inc. is a present-day brand from these days, starting out as the Holt Manufacturing Company. The first mass-produced heavy machine was the Fordson tractor in 1917.

The first commercial continuous track vehicle was the Lombard Steam Log Hauler from 1901. Tracks became extensively used for tanks during World War I, and after the war they became commonplace for civilian machinery such as the bulldozer. The largest engineering vehicles, and the largest mobile land machines altogether, are bucket-wheel excavators, built from the 1920s.