Coaching Notes MC Design 3

One of the great advantages to using the conjugate beam method to compute beam deflections is that the method can handle beams:

with varying cross section and different materials

The easiest, most straight forward method for method beam deflection is the

table look up method

The conjugate beam method of calculating beam deflection allows deflection to be found by drawing

Moment diagrams

When an axial stress is applied eccentrically to a beam, the combined stress due to compression (tension) and bending may be found by

Simple addition

The disadvantage of using the Goodman design criterion of Soderberg design criterion is that it

Requires the material’s ultimate strength to be known

A test for pipe used for coiling in sizes 2 inches

blend

The size of an equal leg length fillet weld shall be based on the length of the largest

Isosceles right triangle

A machine used in testing steel generally strike the specimen with an energy from 220 to 265 ft-lb

Charpy test

One important skill that operators of machine tools must have an understanding of measurements demands:

precision

Which of the following metal is easy to chisel?

cast iron

During the quenching process in heat treating steel, agitation of the fluids used in the quenching has what effect on the severity of the quenching?

Increase quenching severity

In the design of mechanical members, the separation that takes place along in the direction of the highest shearing stress is

Ductile fracture

It is a square key with the bottom two corners are beveled

Barth key

Change in metal structure by which the surface structure recovers from its unstable condition

aging

The ability of a material to absorb energy within its proportional limit

resilience

In kinematics, the occurrence of linear and rotational motion simultaneously is known as

rotakinematics

In kinematics, a single degree of freedom which permits only sliding motion is

prismatic pair

It is the ability of material to absorb plastic deformation

Toughness

Tooth breakage on gear is usually

A tensile fatigue

Pitting is a function of the Hertzian contact stresses between two cylinders and is proportional to the square root of the

Applied load

Is the angle through which the gear turns from the time a given pair of teeth are in contact at the pitch point until they pass out the mesh

Angle of recess

Is the angle through which the gear turns from the time a particular pair of teeth come into contact until they go out of control

Angle of action

A type of coupling that allows slight amount of torsional/ angular flexibility due to introduction with some material cylindrically wrapped around the bolts in the flange

Elastic material bushed coupling

In uniformly loaded beam, the maximum vertical shearing force occurs

At the end supports

A type of roller bearing in which the balls are assembled by the eccentric displacement of the inner ring

deep groove ball bearing

The effectiveness of the brake may greatly decrease shortly after it begins to continuously

fade

Occurs when the oil film fails, but in this case, the load and the speed are so high that the surface metal is melted and the metal is smeared down the profile

scoring

The extra tooth in gear which is used to distributes the wear more evenly

Hunting tooth

A gear that has an advantage of smoother tooth engagement, quietness of operation, greater strength and higher permission speeds

spiral bevel gear

Amount of automatic feed in shaper is increased by taking the crank pin

Away from the center of a crank disc

In a shaper, the feed (metric) is usually expressed in

mm/stroke

For cutting gear teeth in a shaper, the

form

Shaper tool bit should not extend in tool holder beyond

15 mm

The standard ratio of cutting to return stroke in shaper is

3:2

A tipped tool is more useful than a H.S.S tool because

all of the above

The feed in a shaper takes place at

the end of return stroke

When two touching surfaces have high contact pressure and when these surfaces have minute relative motion, a phenomenon called

fretting

Is the process of cold works where a limited amount of material, resulted to a higher strength and it leaves a surface under compressive stress

surface rolling

When a hot part is cooled suddenly by quenching , there is momentarily a high temperature gradient that includes a stress gradient. Some metal parts under certain conditions crack as a result of this phenomenon which is called

thermal-shock failure

Is a low cost spring material, suitable where service is not a severe and dimensional precision is not needed

hard drawn wire spring

Is a spring wire with good quality for impact loads and moderately high temperature

chromium-silicon

Is a type of coil where the helical coil i9s wrapped into a circle forming an annular ring

garter spring

In a planer the feed is provided

at return stroke

In a planer the cutting speed depends upon

material of job, material of tool and feed rate  

If length of the planer stroke is 450 mm, number of stroke per minute are 10, then cutting speed will be

7.5 meter/min.

The planer tool differs from the lathe tool because it has

less front and side clearance  

The cutting action in on both strokes in

universal planer

The straddle milling is done by means of two

side milling cutters

The formula to find out the number of turn of the crank simple indexing is

T=40/N

A method whereby a gear is run with another gear that has abrasive surface material

lapping

The ability of the material to absorb energy within its proportional limit is known as

resilience

In pure torsion, the maximum torsional stress is at the center of the

long sides

When tested in compression, ductile materials usually exhibit __________ characteristics up to the yield strength as they do when tested in tension

approximately the same

In a pressure vessel, the ratio of minimum strength of joint to the strength of solid joint is known as

relative strength

A tolerance where the size of a part is permitted to be either larger or smaller than the given dimension

bilateral

If a clearance of a cutting edge is 15 deg, the lip (wedge) angle in 75 deg, the rake angle will be

10 deg

The cross feed rod is 5mm pitch and the graduated collar has 250 graduation. If 15 divisions depth of cut is given, the reduction in diameter will be

0.3 mm

The approximate hardness of HSS end mill cutter is

62 HRC

The over arm of a milling machine is used to support

arbor

Where the feed motion takes place in a slotting machine

after each double stroke

Which of the following conditions may cause error during knurling?

to much longitudinal feed  

Mark the milling method during which the formation of the chatter marks is very likely

during up cut milling with a straight tooth cutter  

Intrinsic silicon becomes intrinsically conductive with electrons as majority carriers, when doped with which of the following?

Antimony

All of the following group of plastics and thermoplastics, EXCEPT

Phenolics, melamine and epoxy

All of the following statements about rusting of iron are correct, EXCEPT

Pitting occurs in oxygen rich anodic areas and the rust is deposited nearby

At quite low temperature (say -75 C) the notched bar impact value of steel

Decreases significantly

Materials with low values of thermal expansion are desirable for

Pyrex glassware

Individual rigidity values

Have no significance

An advance motion along the longitudinal axis of a twist drill is called

Feed

In internal cylindrical grinding, the grinding wheel and the work rotate in

Opposite direction

For grinding materials having low tensile strength which abrasive is used

Silicon carbide

The size of grinding wheel is taken from

All of the above

Which centre is used for supporting open end of pipes, shells, etc. turning or thread cutting in a lathe?

Pipe centre

When outside diameter of a job is turned in relation to the internal hole, the job should be held

On lathe mandrel

Included angle of a dead center is

60 deg

Machining of properties of steel can be improved by adding

Sulfur, lead, phosphorous

A behavior of metals wherein strength of metal is increased and ductility is decreased on heating at a relatively low temperature after cold working, is called

Strain aging

Point of arrest of iron corresponds to

Stages at which allotropic forms change

The column of splice is used for increasing

Length of the column

A rolled steel shaft designed as 50 ISF 8 means

The flat is 50 mm wide and 8 mm thick

A shaft rotating in anti-clockwise direction at low speed inside a bearing will be

Towards left side of the bearing metal to metal contact

Which gauge is used to check the internal threads?

Thread plug gauge

In case of a limit plug gauge which size will not enter into the hole

‘not go’ size

Limit gauge is made to the _______ sizes of the work to be measured

Maximum and minimum

‘Go’ limit is

Both

Lapping is done

All of the above

In which method a bore is finished to a vey close tolerance

Honning

Jig bushing is generally made of

Tools steel

A tolerance where the size of a part may larger only, or smaller only, than the given dimension

unilateral

Is the relatively finely spaced irregularities of the surfaces

roughness

Is the irregularities or departures from the nominal surface of a greater spacing than the roughness

waviness

It has been said that 80% of the failure of the machine parts have been due to

fatigue

In a part uniform temperature and not acted upon by an external load, any internal stresses that exist are called

form stress

Is a process of prestressing or overstressing a hollow cylindrical member beyond the elastic range by hydraulic pressure

autofrettage

Which of the following quick return mechanism is most widely used in most of the slotters

Whitworth mechanism

In a slotter the cutting speed depends upon

Material of the slotter tool

If the clearance angle is more than the required on a slotter tool, the support on cutting edge will be

less

Convex shaped slotter tools are used for machining

Concave surface

The clamping block to be used in a slotter to support the end of the strap is made of

wood

The table for slotter has feeding movements

all of the above