Design And Construction Of A Mechanical Vibration System For Application In Sieving Of Sand.
Abstract
Sand is a valuable non-renewable commodity used for building in this rapidly growing global
construction market. It is one of the highest volumes of raw materials used in the construction
industry after water. Due to several advancements in techniques of construction, the quality of
sand has been critically considered. For example; plastering or wall finishes largely requires fine
smooth sand particles, foundry work also requires fine sand particles to ensure good surface finish.
This has led to processes like sieving where sand particles are separated according to particle sizes.
Various sieving machines have been invented such as rotary and vibratory sieving machines which
are electrically powered. However, the widespread use of these innovations is still low due to the
problem of unaffordability (high purchase prices), high daily expenses on electricity (1unit of
UMEME electricity is approx. Ugshs 700) and low incomes of users.
The builders and construction companies therefore, still rely on the traditional sieving method
which is equally inefficient because it requires 3 operators, it’s unsafe (due to dust emitted),
exhausting (requires lifting and shaking of sieve with hands) and produces a low output per unit
time (0.7m3 /hr.). This has often led to delays in work completion as well as increased operation
costs (paying operators).
In order to solve this problem, the author proposed the design and construction of a sieving
machine that uses a mechanical vibration system to sieve the dry sand. Several design procedures
were undertaken as illustrated in the proceeding Chapters to fabricate a working prototype of the
machine.
After various tests on the fabricated prototype, it was noted that the machine solved this problem
as it increased the sieving rate from 0.7m3 /hr. to 1.2m3 /hr. with only one operator. The machine
is energy efficient as it is only hand cranked periodically (no need to carry and shake). The machine
is also affordable (approximately Ugshs. 700,000) and maintainable since it’s made from readily
available materials. It is also comprised of some secondary features like portability and flexibility
(can be used to sieve and sort agricultural produce like beans)