Page 96 - CITS - WCS - Mechanical

WORKSHOP SCIENCE - CITS

Screw Jack: A jack screw jack or jackscrew is a mechanical device used as a lifting device to lift heavy loads by
applying minimal forces. A hydraulic jack uses hydraulic power. The most common form is a car jack floor jack or
garage jack which lifts vehicles so that maintenance can be performed.

A jackscrew, or screw jack, is a type of jack that is operated by turning a lead screw. It is commonly used to lift
moderate and heavy weight, such as vehicles; to raise and lower the horizontal stabilizers of aircraft; and as
adjustable supports for heavy loads, such as the foundations of houses.

A screw jack is a gearbox assembly (either worm gear or bevel gear) and a transmission product (lead screw,
ball screw or roller screw) which through use of a motor is used to convert rotary into linear motion. They can be
used to push, pull, tension, lock, unlock, tilt, pivot, roll, slide and lift or lower loads, anything from a few kilos to
thousands of tonnes. Screw jack material: Aluminium AC43100, cast iron G25 UNI 5007, cast iron GS400 UNI
4544, stainless steel AISI 316 (ASTM A 351 CF8M).
Wheel and Axle: The wheel and axle is a type of simple machine used to male tasks easier in term of manipulating
force by applying the concept of mechanical advantage.

The wheel and axle consists of a round disk, known as a wheel, with a rod through the centre of it, known as the
axle.
Describe
Two rounded objects that move together

The larger object is the Wheel
The smaller object is the Axle
The larger the wheel ,The longer the distance and the greater the MA.

Various examples of what a wheel and axle is used for in our everyday life include:
• Car tires.
• Bicycle.
• Ferris wheel.
• Electric fan.

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CITS : WCS - Mechanical - Exercise 8 CITS : WCS - Mechanical - Exercise 8