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

Manufacturing methods of ceramics, Manufacturing Methods Of Ceramics Th...

Manufacturing Methods Of Ceramics The ceramics manufacturing consists in shaping along with or without pressure and firing to consolidate. The simplest and cheapest process of

Kinematics of machine, what is the cross head velocity in slider crank mech...

what is the cross head velocity in slider crank mechanism.

Elements of cad, Human Factor : The human factor is the key factor in th...

Human Factor : The human factor is the key factor in the success of CAD system. This concerns the training of the designer or the engineer without whom the CAD system become

Solved numarical, The following observations were made during a tensile tes...

The following observations were made during a tensile test on mild steel specimen 60 mm in diameter and X mm long. Elongation with 50 KN load (within the limit of proportionality)

Maximum stress in each material, The maximum stress in each material: ...

The maximum stress in each material: A copper tube of external diameter 60 mm and internal diameter 40 mm is closely fitted to a steel rod of 40 mm diameter to compose a compo

What is the pressure difference between the stations , (Bernoulli equation ...

(Bernoulli equation along a streamline) Water flows from station (1) to (2) around an expanding corner pipe, 3m high. The speed along the center streamline is 10 m/s at (1) and 5

Selection of electrodes and filler metals, Q. Selection of Electrodes and F...

Q. Selection of Electrodes and Filler Metals? Only low hydrogen electrodes shall be used for SMAW of all carbon and low alloy steels, except for root pass welding of single wel

Best air pressure, Research on Best air pressure :             Once we ...

Research on Best air pressure :             Once we had green light to go on with sand blasting process. We had conducted a few experiment testing and analysis. First of all we

Determine the bending stress, The cantilevered beam made from the Z section...

The cantilevered beam made from the Z section is subjected to the two loadings as shown. (a)  Determine and show the orientation of the neutral axis on the cross section (angle

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