Interview Questions.

Question 1. What Is The Application Of Dowel Pins?

Answer :

Dowel Pins are typically used to align two elements for assembly.

Question 2. What Is The Effect Of Grain Direction In Sheet Metal Bending?

Answer :

When Sheet metal is synthetic with bloodless rolling manner, Grain shape of sheetmetal is aligned within the course of rolling. For the softer materials if bending is executed in rolling direction it will bring about cracks. It is always prefered to do bending inside the course perpendicular to rolling course.

Mechanical Engineering Interview Questions
Question three. What Are Commonly Used Sheet-steel Assembly Process?

Answer :

Screws: Self tapping Screws, Machine Screws
Welding : Arc Welding, TIG Welding, MIG Welding
Folding Techniques: Lap Joint, Hem Joint Riveting
Press Fitting: PEM Inserts
Question four. What Is Some Common Reinforcement Techniques Used To Improve The Strength Of The Sheet Metal Parts?

Answer :

Generally following Techniques are used:

Bending: ordinary bend, hem bend
Forming tools: sheet-steel rib, louver, lance & Tab 
Question five. What Are Some Common Design Parameters Need To Be Considered While Material Selection For Sheet Metal Parts Is Done?

Answer :

Following are the commonly parameters want to keep in mind:

Product IP-Rating
Working Temprature
Corrosion Resistance
Part Strength Requirement
Part Weight
Final Finish Requirements
Part joining Methods (Riveting/Welding/Screw)
Question 6. What Is Minimum Hole/slot Distance From Edge?

Answer :

Minimum Distance = three X Sheet Thickness + R (Inside Bend Radius)

Question 7. What Is The Minimum Flange Length In Sheet-metallic Bend?

Answer :

The minimum flange length should be kept 4 instances of sheet thickness plus interior radius

Minimum Flange duration = four X T (sheet thickness) + R (Inside Bend Radius)

Question eight. Explain What Is Blue Print Reading?

Answer :

Blueprint reading is sort of a structural map that covers the steel structure.  It is a detail drawing of metal shape, and it incorporates a label or piece mark to distinguish one metal bar or structure from others.  Each piece or segment of metal structure has a unmarried blueprint with particular information before it end up the a part of the whole.  It consists of data even small as hole sizes, size, etc.

Question nine. Mention Few Surface Coating Process Form Sheet Metal Brackets?

Answer :

Phosphate coating ZP12,,
CED Black Coating ,
CATION type electro deposition coating after Phosphating
Question 10. What Is The Necessity Of Surface Treatment Process In Sheet Metal Components?

Answer :

Surface remedy is important for sheet metal parts in-order to prevent corrosion , protect the element shape mechanical harm, guard the component because of temperature adjustments, to provide extra strength, sturdiness, to enhance aesthetic appearance, to guard towards rust.

Zinc plating, Nickel plating, Anodizing, Tinning, Dip coating and powder coating are some of the familiar floor remedy techniques accompanied for sheet steel additives.

Question 11. What Are All The Surface Finish Processes Used For Sheet Metal Fabrication?

Answer :

Powder coating is a usually used floor finishing technique. It is a type of coating this is carried out as a loose-flowing, dry powder.

Question 12. What Is K-thing In Sheet Metal Fabrication?

Answer :

As defined in bend allowance, when sheet steel is bent, the inner floor of the bend is compressed and the outer surface is stretched, but somewhere inside the thickness of the metallic lies its Neutral Axis, that's a line inside the metal that is neither compressed nor stretched.

The area of the impartial line varies relying on:

the material itself, 
the radius of the bend,
the ambient temperature, 
path of the cloth grain, 
and the technique by way of which it's miles being bent, and many others. 
The vicinity of this impartial line is known as the K-component.

Many CAD programs also training session bend allowances robotically by way of the usage of K-element calculations.

K-element is a ratio that represents the vicinity of the neutral line with admire to the thickness of the sheet steel.

Mechanical Engineering Interview Questions
Question thirteen. What Is Meant By Bending Allowance In Sheet Metal Fabrication ? How To Calculation Bending Allowance?

Answer :

Bend allowance comes from the fact that when sheet steel is bent, the internal floor of the bend is compressed and the outer floor of the bend is stretched (elongated).

So, while we need a 90 diploma bend wherein one panel side has a length of A, and the other panel aspect has a period of B, the total period of the flat piece will NOT be A+B, however as a substitute equals A+B plus a bend allowance or A+B minus a bend deduction(depending on how we measure A and B).

So bend allowance is a term which describes how tons material is needed between two panels to house a given bend. Determining bend allowance is usually referred to as “bend improvement” or definitely “development”.

Question 14. What Common Methods Of Welding, Would Be Associated With Sheet Metal Fabrication?

Answer :

Depending on your sheet metal layout, you can choice spot-welded enclosures or fully seam-welded enclosures. With many enclosure designs, consisting of our popular U-form (clam shell), no welding is required. One section of the enclosure includes small flanges with self-clinching nuts and the alternative phase of the enclosure is mounted using mechanical fasteners consisting of system screws or sheet metallic screws.

Spot welding might be utilized in cases in which disassembly isn't required. Fully seam welded edges will also be a requirement, mainly if the application requires a greater tightly sealed enclosure.

Question 15. What Is The Standard Bending Radius Followed During Sheet Metal Fabrication?

Answer :

Sheet steel enclosures are normally fabricated via 'bloodless forming' approach, wherein the metal is clamped and bent in machines known as 'press brakes'. Because of this, metal usually can not be fashioned into a real ninety degree corner. Instead, the corners are curved or filleted in practical that is technically denoted as bend radius,

Different tiers of curvature may be executed and Note that bend radius is detailed as the radius of the INSIDE surface of the bend

Question sixteen. What Are Precision Sheet Metal Components?

Answer :

Sheet metallic additives which can be made the use of excessive precision dies with sheet of close tolerance in machines with excessive balance are generally known as as precision sheet metallic components. The precision of the element has to be decided based on the cause that the additives goes to serve,

Question 17. How Is Sheet Metal Components Formed?

Answer :

Sheet steel components are commonly metallic fashioned through diverse forming techniques majorly involving Bending, deep drawing, Roll forming, Stamping, Punching, Piercing etc. The sheet metals are initially received as Rolls and cut into plain blankets after which fashioned into favored shape the use of above stated tactics particularly bending and stamping.