Process selection and sequencing, Mechanical Engineering

Assignment Help:

Process Selection and Sequencing

In this, some factors, which have an influence in all processes, are discussed. The factors include size, shape complexity, tolerances and production volume.

After product consideration, selection of sequence of process is greatly influenced by the characteristics of the manufacturing processes. Hence a brief treatment of various manufacturing process right from casting to welding are discussed.

In all casting processes, a metal or alloy is melted, poured into a mold, allowed to solidify and the part thus produced is released from the mold. Very broadly, casting processes fall into two groups: expendable-mold and permanent-mold processes. Choice of process and mold material is greatly influenced by the melting point of the alloy.

All plastic deformation processes exploit the ability of metals and alloys to change shape by plastic flow. The ability to deform without fracture is highly variable. Bulk deformation processes impose material flow in all directions, and the ability to deform is expressed as workability; in sheet metal working processes deformation is essentially two-dimensional, and limits of deformation are referred to as formability. It is important to recognize that the limits of plastic deformation are the outputs of a system and these are greatly affected by the stress state prevailing in the process.

Powder processing involves a sequence of operations. The powder is produced by various techniques: reduction of an oxide, thermal decomposition, electrolysis, hydrometallurgy, or breaking up (atomizing) a melt. Particle size is controlled during powder production or by comminution; size fractions are separated by sizing. After cleaning (and possibly annealing), alloying elements and lubricants are added by blending. There are several process routes to arrive at finished parts.

Parts produced by casting, deformation, and powder processing techniques frequently require some metal removal to create the final shape, meet tolerances, or obtain the requisite surface finish. Machining may also be an economical alternative to create the shaper from a semi fabricated product such as bar or plate. Metal may be removed by chip formation or by less conventional, noncutting techniques.

A good manufacturing sequence is always determined by selecting suitable terminal points. Hence such a sequence must begin and end with part prints. Before formulating any process plan, the process engineer find out what is wanted in the final product. At the end of manufacturing sequence, the process engineer must again make reference to the part print to determine by comparison whether or not the final product can meet all design specifications.


Related Discussions:- Process selection and sequencing

Rich mixture-mixture requirement , Rich Mixture: It generally ranges...

Rich Mixture: It generally ranges from approximately 7 : 1 to 13 : 1 proportion of air to fuel by weight. To get a high power rich mixture is required. In fact to start the e

Steam generator master pressure control, Q. Steam Generator Master Pressure...

Q. Steam Generator Master Pressure Control? The combined header pressure is controlled by a regular P.I.D. controller which ultimately trims the water flow to each boiler. A

Physics, show that the avogadro constant is the number of atoms in 0.072kg ...

show that the avogadro constant is the number of atoms in 0.072kg of carbon-12

Trippaing, how thw trippaning process work

how thw trippaning process work

Construct the load displacement diagram, A suspended walkway in an undergr...

A suspended walkway in an underground cavern consists of a deck supported by three tie rods placed symmetrically about the centre as shown below: The rods are each of

What will be the alteration of pressure, A copper tube 1.2 m long, has 80mm...

A copper tube 1.2 m long, has 80mm internal diameter and 2 mm wall thickness. It has closed ends, and is filled with water under pressure. What will be the alteration of pressure i

Rotational-mechanics, A straight rod of length L is released on a friction ...

A straight rod of length L is released on a friction less horizontal floor in a vertical position . As it falls( also slips) , the distance of a point on the rod from the lower end

Define advantages of welding process, Advantages of welding process Wel...

Advantages of welding process Welding results in a good saving of material and reduced labour content of production. Low manufacturing costs. Dependability of the me

Explain concept of tapping of radial drilling machine, Explain concept of T...

Explain concept of Tapping of radial drilling machine Tapping:- Tapping is the method by which internal threads are produced. It is performed either by hand or by machine.

Explain the application of electro chemical machining, Explain the Applicat...

Explain the Application of Electro Chemical Machining? 1. EBM has been used to perforate holes in glass fiber spinning head made from a heat resistant supper alloy. 2. Slott

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