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major drawback of this type of machine is the reciprocating action of ram which is time wasting since the ram must be withdrawn after its power stroke and a new dolly of material inserted in the container.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

Explain the tool angle, What is Tool Angle? The several angles influenc...

What is Tool Angle? The several angles influence tool performance to a considerable extent & therefore their value should be selected with great care & consideration. a) It

Current-fundamentals of electricity , Fundamentals of Electricity Cu...

Fundamentals of Electricity Current: The flow rate of charge or electrons with respect to time is known as current. It is measured in ampere (A).

Crankshaft-basic components of engine , Crankshaft : It converts the recip...

Crankshaft : It converts the reciprocating motion of the piston into useful rotary motion. In the crankshaft of a single cylinder engine, there is a pair of crank arms and balance

Derive the expression of torque in closely excited system., Q.   Derive the...

Q.   Derive the expression of torque developed in closely excited magnetic system. Clearly explain then assumption made.   Sol. Double - Excited System   A doubly - ex

Split queue rules-priority rules-conventional priority rules, Split Queue R...

Split Queue Rules SPT*   Two queues prioritized as per to SPT. The operations for that t sj - u is negative form a high priority queue that is processed first. The order insid

Sketch merchants force diagram, Merchants force diagram. State the assumpti...

Merchants force diagram. State the assumptions made in development of such diagram.

Ultrasonic welding, ULTRASONIC WELDING This is a solid state welding p...

ULTRASONIC WELDING This is a solid state welding process for joining similar or dissimilar metals by application of high frequency vibratory energy to work pieces held togethe

DESIGN, HOW DO I DESIGN A COMPONENT FOR IMPACT STRENGTH FOR IMPACT LOAD AT ...

HOW DO I DESIGN A COMPONENT FOR IMPACT STRENGTH FOR IMPACT LOAD AT LOWER TEMPERATURE

Evaluate force and moment - mechanics, Evaluate force and moment: Wha...

Evaluate force and moment: What force and moment is transmitted to supporting wall at A   A force of 15 KN is transmitted to wall along with anticlockwise mome

Determine number of coils and length of the spring, Determine number of coi...

Determine number of coils and length of the spring: A close coiled helical spring ought to extend by 120 mm under an axial force of 1200 N. If mean coil radius is equal to 40

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