Describe the extrution process, Mechanical Engineering

Assignment Help:

Q. Describe the extrution process?

The extrusion process, in many cases produces material in an intermediate form for subsequent reprocessing to its final component form. The process is the same as for metals, that is, the expulsion of material through a die of the required cross-section. Simplicity in operation and a controlled pressure which can be virtually high as required. If the polymer can be plasticized by pressure, then the ram extruder is advantageous in view of its simplicity. But for plastics which require heat, the separate pre-processing mat be regarding as a draw back. Another major drawback of this type of machine is the reciprocating action of ram which is time wasting since the ram must be withdrawn after its power stroke and a new dolly of material inserted in the container. Also, with many materials, the die office must be cleaned between each working stroke.

Nowadays, the ram machine is mainly used for "wet extrusion" that is for extruding plastics which have been softened by the addition of solvents. Solvent has to be removed.

For extrusion of plastics, single-screw machine has completely replaced the ram type machine. There are two basic types of screw extruders: the melt extruder and the plasticizing extruder. In the formal, the material is delivered to the extruder already melted and thus the function of the extruder is merely to push the material to the die and through the orifice. In the plasticizing extruder the material is in the form of granules or particles and so the extrude has to compress and work it until it melts before delivering it, under pressure, to the die orifice.


Related Discussions:- Describe the extrution process

Determine the reactions at beam, Determine the reactions at bea: A can...

Determine the reactions at bea: A cantilever AB, 1.8 m long is fixed at A and carries uniformly distributed load of 20 kN/m over its entire length and a point load of 30 kN at

Sizing a solar pv system, The Rusk's own fairly large house near San Franci...

The Rusk's own fairly large house near San Francisco and the following spreadsheet shows their month to month power use for two years.  1. What is their monthly average power us

Ventilation process of plant, Q. Ventilation process of plant? Due to t...

Q. Ventilation process of plant? Due to the possibility of accidental discharges of flammable gas and flashing liquid (e.g. leaks, incorrect valve opening, sampling, etc.); ade

Trippaing, how thw trippaning process work

how thw trippaning process work

Advantages-disadvantages of transparent polymeric, (a) List several advanta...

(a) List several advantages and disadvantages of using transparent polymeric materials for eyeglass lenses. (b) Cite four properties (in addition to being transparent) that are

Automobiles industry growth , AUTOMOBILES INDUSTRY GROWTH: The Indian auto...

AUTOMOBILES INDUSTRY GROWTH: The Indian automobile industry has a significant labour cost advantage. India's automotive sector has the world's second largest pool of skilled labou

Explain about surface preparation, Q. Explain about Surface Preparation? ...

Q. Explain about Surface Preparation? All oil, grease, salts, and any other contaminants detrimental to the formation of a good coating bond or coating quality must be removed

Boilers, What is meant by boiler mountings

What is meant by boiler mountings

Calculate additional force required to maintain equilibrium, Calculate Addi...

Calculate Additional force required to maintain equilibrium: Fo r the system shown in figure find the additional single force required to maintain equilibrium. Sol.: L

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd