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WorksheetsMACHINE SHOP & DESIGN PRACTICES
Total questions: 201
Worksheet time: 10hrs 3mins
This radial distance in a gear is measured between the addendum and dedendum circle, and is the sum of the addendum and the dedendum? How do you call this distance?
a) Addendum
b) Whole depth
c) Working depth
d) Space width
What is the polar section modulus of a solid shaft with a diameter of 101.6 mm?
209.5 cm3
209.5 cm4
205.9 cm3
205.9 cm4
This minimum distance is measured between the non-driving side of a tooth and the adjacent side of the mating tooth. It is the amount by which the width of a tooth space exceeds the thickness of the engaging tooth measured on the pitch circle. What is this distance?
Circular pitch
Whole depth
Backlash
Space width
With the water interruptions prevailing in your town, you have been asked to design an upright cylindrical water tank 6 meters in diameter and 6 meters high, vented, and to be filled completely with water. Determine the minimum thickness of the tank plate if the stress is limited to 40 Mpa.
3.3 mm
4.4 mm
5.5 mm
8.8 mm
What is the algebraic difference between the maximum limit and the corresponding basic size?
Fundamental deviation
Upper deviation
Lower deviation
Tolerance
A steel shaft 1.75 inches in diameter transmits 40 Hp at 1800 rpm. Assuming a modulus of rigidity of 12 x 106 psi, find the torsional deflection of the shaft in degrees per foot length.
0.0073
0.0037
0.0063
0.00013
What is the algebraic difference between the minimum limit and the corresponding basic size?
Fundamental deviation
Upper deviation
Lower deviation
Tolerance
A helical-coil spring has a mean coil diameter of 1 inch and a wire diameter of 1/8 inch. Determine the curve correction factor of the spring.
1.144
1.44
1.1144
1.1414
This is either the upper or the lower deviation, depending on which is closer to the basic size. How do you call this deviation?
Fundamental deviation
Upper deviation
Lower deviation
Tolerance
A vise is equipped with a 1-inch single square thread, with 4 threads per inch. The frictional radius of the collar is 0.5 inch. The coefficient of friction for both the collar and threads is 0.20. How much external torque must be applied to produce a force of 200 lb against the jaws of the vise?
39.73 in-lb
33.97 in-lb
37.93 in-lb
39.37 in-lb
What is the difference between the maximum and minimum size limits of a part?
Allowance
Tolerance
Deviation
Basic size
A helical-coil spring has a mean coil diameter of 1 inch and a wire diameter of 1/8 inch. Determine the Wahl factor of the spring.
1.148
1.184
1.418
1.814
It is the capacity of a material to absorb energy when it is deformed elastically and then, upon unloading, to increase this energy. What is this capacity of a material?
Resilience
Toughness
Rigidity
Ductility
A helical-coil spring has a mean coil diameter of 1 inch and a wire diameter of 1/8 inch. Determine the value of Bergstrassar factor of the spring.
1.172
1.712
1.217
1.271
How do you call the strain energy per unit volume required to stress a material from an unloaded state to the point of yielding?
Modulus of roughness
Modulus of elasticity
Modulus of rigidity
Modulus of resilience
Compute the tooth thickness of a 14.5o spur gear with diametral pitch of 5.
0.23140 inch
0.31416 inch
0.43140 inch
0.03140 inch
How do you call a structural member designed to support loads perpendicular to its longitudinal axis?
Cantilever beam
Beam
Overhanging beam
Column
Compute the speed of the gear mounted on a 52.5 mm diameter shaft receiving power from a driving motor with 250 Hp.
2 182 rpm
2 071 rpm
2 265 rpm
2 341 rpm
It is a load applied transversely to longitudinal axis of member. How do you call this load? a) b) c) d)
Bending load
Combined load
Distributed load
Cyclic load
What is a load distributed over an entire area?
Bending load
Combined load
Distributed load
Cyclic load
Compute the working strength of 1 inch bolt which is screwed up tightly in packed joint when the allowable working stress is 13000 psi.
3 600 lb
3 950 lb
3 900 lb
3 800 lb
It is a design approach where no catastrophic loss can occur as a result of a component failure. What is this design approach? a) b) c) d)
Fail-safe design approach
Fault free analysis approach
Manifest danger approach
Redundancy approach
. Compute the nominal shear stress at the surface, in MPa, for a 50 mm diameter shaft that is subjected to a torque of 0.48 kN-m. a) b) c) d)
16.95
21.65
19.56
25.12
How do you call a statistical data used to identify the most likely failure modes?
Finite element analysis
Fault free analysis
Failure analysis
Random analysis
A hollow iron pipe to be designed as a column has an outside diameter of 240 mm and is subjected to a force of 80 KN. Find the pipe thickness if the compressive stress is limited to 16 MPa.
5.85 mm
6.85 mm
7.85 mm
8.85 mm
It is a computational method used for solving complex shapes, such as those found in machinery; replaces the complex shape with a set of simple elements interconnected at a finite set of a specific purpose. What is this computational method?
Finite element analysis
Numerical method of analysis
Fault free analysis
Synthesis
A uniform beam 12 meters long is fixed at one end. It has a uniform weight of 50 kg/m along its length. A load of 20 kgs. is suspended on the beam 4 m from the free end. The moment at the fixed end is
3760 kg-m
0.0 kg-m
60 kg-m
4800 kg-m
When a hot part is cooled suddenly by quenching, there is momentarily a high temperature gradient that induces a stress gradient. Some metal parts under certain conditions crack as a result. How do you call this phenomenon?
Thermal-shock failure
Thermal fatigue
Honing
Quenching
A 20o straight-tooth bevel pinion having 14 teeth and a diametral pitch of 6 teeth/inch drives a 42-tooth gear. The two shafts are at right angles and in the same plane. Find the pitch angle of the pinion.
18.4o
20o
14.5o
20.5o
. How do you call the diameter of the imaginary cylinder that bounds the crest of an external thread and the roots of an internal thread?
Mean diameter
Stress diameter
Minor diameter
Major diameter
A 20o straight-tooth bevel pinion having 14 teeth and a diametral pitch of 6 teeth/inch drives a 32-tooth gear. The two shafts are at right angles and in the same plane. The pinion is to transmit 1800 rpm and transmitting 50 hp. Determine the pitch diameters of the gears.
2.33 inches and 5.36 inches
3.23 inches and 3.56 inches
5.36 inches and 6.36 inches
2.33 inches and 2.33 inches
It is a measure of the change in length of a material subjected to a change in temperature. How do you call this property of the material?
Toughness
Coefficient of thermal expansion
Thermal conductivity
Electric Resistivity
A 1-inch diameter shaft has a single disc weighing 75 lb mounted
midway between two bearings 20” apart. Find the lowest critical
speed in rpm. Neglect the weight of the shaft. Assume that the
modulus of elasticity is 30 x 106
psi.
a) b)
c) d)
2038 rpm
2308 rpm
2380 rpm
2038 rpm
What is a condition where one surface is comparatively free of stress? a) b) c) d)
Octahedral plane
Biaxial or Plane stress
Strain plane
Principal normal stress
. A flywheel weighing 457 kg has a radius of 375 mm. How much energy, in N-m, does the flywheel loss from 3 rps to 2.8 rps? a) b) c) d)
368
150
1474
38
How do you call the circle on a gear that corresponds to the contact surface of the friction wheel?
Addendum circle
Root circle
Pitch circle
Base circle
A triple threaded worm has a pitch diameter of 3 inches. The wheel has 25 teeth and a pitch diameter of 5 inches. Material for both the wheel and the wheel is phosphor bronze. Determine the helix angle of the gear.
11.31o
13.11o
11.13o
10.13o
This material is the most popular alloy spring steel for conditions involving higher stresses than can be used with the high-carbon steels and for use where fatigue resistance and long endurance are needed; this is also good for shock and impact loads.
Chrome silicon
Chrome vanadium
hard-drawn wire
Oil-tempered wire
What is the largest roller chain size that can be used for power transmission at a sprocket speed of 1000 rpm?
RC 35
RC 50
RC 80
RC 60
These are gears with teeth formed on conical surfaces and are used
mostly for transmitting motion between intersecting shafts. How do
you call these gears?
a) b)
c) d)
Spur gears
Helical gears
Bevel gears
Worm gearings
A single square thread power screw is to raise a load of 70 kN. The screw has a major diameter of 36 mm and a pitch of 6 mm. The coefficient of thread friction and collar friction are 0.13 and 0.10 respectively. If the collar mean diameter is 90 mm and the screw turns at 60 rpm, find the axial linear speed of the screw. a) b) c) d)
5 mm/s
6 mm/s
7 mm/s
5.5 mm/s
A double thread ACME screw driven by a motor at 400 rpm raises the attached load of 900 kg at a speed of 10 m/min. The screw has a pitch diameter of 36 mm; the coefficient of friction on threads is 0.15. The friction torque on the thrust bearing of the motor is taken as 20 % of the total input. Determine the lead angle. a) b) c) d)
12.465o
14.265o
15.462o
16.452o
What Hp can a 1-inch diameter short shaft transmit at 380 rpm?
3 Hp
18 Hp
10 Hp
7.1 Hp
A spur pinion rotates at 600 rpm and transmits 25 kW to a mating gear. The pitch diameter of the pinion is 100 mm, and the pressure angle is 20o . Determine the tangential load, in N.
7660
6790
3900
3098
A bearing that primarily guides the motion of a machine member without specific regard to the direction of load application.
Journal bearing
Clearance bearing
Guide bearing
Thrust bearing
A multiple-disk clutch, composed of three plates with a small diameter of 150 mm and large diameter of 200 mm, is designed to transmit 100 kW at 3000 rpm at a coefficient of friction of 0.5. Determine the spring force needed to engage the clutch.
2820 N
2428 N
5460 N
3638 N
A wire rope lifts a load of 10 kips at a maximum speed of 1000 feet per minute, attained in 5 seconds starting from rest. The rope has a metallic cross sectional area of 0.4 in2 . Determine the maximum tensile stress on the rope in ksi.
26.2
25.0
27.6
32.4
What is the bursting steam pressure of a hemispherical steel shell with a diameter of 100 inches and made of 0.0635-m thick steel plate, if the joint efficiency is 70 % and the tensile strength is 60 000 psi?
4 020 psi
4 200 psi
2 400 psi
2 040 PSI
0. A cylinder having an internal diameter if 508 mm and external diameter if 914.4 mm is subjected to an internal pressure of 69 MPa and an external pressure of 14 MPa. Determine the hoop stress at the inner surface of the cylinder. a) b) c) d)
90.11 MPa
91.10 MPa
911.0 MPa
19.10 Mpa
What length of a square key is required for a 4-in diameter shaft transmitting 1000 hp at 1000 rpm? The allowable shear and compressive stresses in the key are 15 ksi and 30 ksi, respectively.
2.1 inches
2.8 inches
3.2 inches
4.2 inches
What length of a square key is required for a 4-in diameter shaft transmitting 1000 hp at 1000 rpm? The allowable shear and compressive stresses in the key are 15 ksi and 30 ksi, respectively. a) b) c) d)
2.1 inches
2.8 inches
3.2 inches
4.2 inches
Which of the following are the compositions of stainless steel 302? a) b) c) d)
18 % chromium and 8 % nickel
18 % nickel and 8 % chromium
18 % chromium and 8 % phosphor bronze
18 % bronze and 8 % vanadium
The root diameter of a double square thread is 0.55 inch. The screw has a pitch of 0.2 inch. Find the number of thread per inch.
0.2 threads/inch
10 threads/inch
5 threads/inch
2.5 threads/inch
A single square thread power screw is to raise a load of 70 kN. The screw has a major diameter of 36 mm and a pitch of 6 mm. The coefficient of thread friction and collar friction are 0.13 and 0.10 respectively. If the collar mean diameter is 90 mm and the screw turns at 60 rpm, find the combined efficiency of the screw and collar. a) b) c) d)
15.32 %
12.53 %
13.52 %
15.97 %
Determine the power capacity of a cone clutch under uniform pressure and assuming the following conditions: major diameter = 250 mm; minor diameter = 200 mm; length of conical elements in contact = 125 mm; rotational speed = 870 rpm; coefficient of friction = 0.30; and allowable pressure = 70 kPa. a) b) c) d)
25.74 Hp
24.75 Hp
27.45 Hp
24.57 Hp
Three extension springs are hooked in series that support a single weight of 100 kg. The first spring is rated at 4 kN/m and the other two springs are rated 6 kN/m each. Determine the equivalent stiffness of the three springs. a) b) c) d)
1.71 kN/m
5 kN/m
2.71 kN/m
3.71 kN/m
These springs are made from one or more flat strips of brass, bronze, steel or other materials loaded as cantilevers or simple beam. a) b) c) d)
Torsion springs
Leaf springs
Garter springs
Drawbar springs
A flat belt is 6 inches wide and 1/3 inch thick and transmits 20 Hp. The center distance is 8 ft. The driving pulley is 6 inches in diameter and rotates at 2 000 rpm such that the loose side of the belt is on top. The driven pulley is 18 inches in diameter. The belt material is 0.035 lb/in3 and the coefficient of friction is 0.30. Determine the belt net tension. a) b) c) d)
201 lb
210 lb
102 lb
120 lb
A pulley 600 mm in diameter transmits 40 kW at 500 rpm. The arc of contact between the belt and pulley is 155o , the coefficient of friction between belt and pulley is 0.35 and the safe working stress of the belt is 2.1 MPa. Determine the belt tensions ratio, neglecting the effect of centrifugal force. a) b) c) d)
2.578
2.857
5.287
5.782
. This refers to the space between adjacent coils when the spring is compressed to its operating length. a) b) c) d)
Coil clearance
Pitch
Lead
Deflection
Select a deep-groove ball bearing to carry a radial load Fx = 800 lb and a thrust load Fz = 700 lb at 1750 rpm. The service is 8 hr/day, but it is not continuous; design for 20 000 hr. The operation is smooth with little vibration; the outer ring rotates. Determine the design life in mr with no more than 10 % failure. a) b) c) d)
20100 mr
2100 mr
2001 mr
1200 mr
Determine the Hp lost when a collar is loaded with 2000 lb, rotates at 50 rpm, and has a coefficient of friction of 0.15. The outside diameter of the collar is 4 inches and the inside diameter is 2 inches. a) b) c) d)
0.7314 Hp
0.3714 Hp
0.4713 Hp
0.4371 Hp
. In a lathe machine, it is the diameter of the largest workpiece it can rotate in a chuck or between centers without hitting the bed.
Chuck diameter
Swing
Distance between centers
Spindle diameter
What load in N must be applied to a 25 mm round steel bar 2.5 m long (E = 207 Gpa) to stretch the bar 1.3 mm? a) b) c) d)
42 000 N
52 840 N
53 000 N
60 000 N
This is a general term that refers to the mating of cylindrical parts such as bolt or a hole; it is used only when the internal member is smaller that the external member. How do you call this?
Clearance
Interference
Allowance
Tolerance
A 50-mm diameter shaft is to transmit 12 kW power at a speed of 500 rpm, determine the mean diameter of the pin, under double shear, for a material having a safe unit stress of 40 N/mm2 . a) b) c) d)
11.08 mm
12.08 mm
13.08 mm
10.08 mm
This is a lubrication condition where non-conformal surfaces are completely separated by lubricant film and no asperities are in contact. How do you call this lubrication condition? a) b) c) d)
Elastohydrodynamic lubrication
Boundary lubrication
Hydrodynamic lubrication
Hydrostatic lubrication
. A 1200 mm cast iron pulley is fastened to 112.5 mm shaft by means of a 28.13 mm square key 175 mm long. The key and shaft have a shearing stress of 14 000 psi. Determine the force acting at the pulley that will shear the key. a) b) c) d)
10 015 lb
11 005 lb
11 050 lb
10 501 lb
A 75-mm diameter shaft is transmitting 350 kW at 650 rpm. A flange coupling is used and has 6 bolts, each 18 mm in diameter. Find the required diameter of the bolts circle based on an average shearing stress of 27.5 MPa. a) b) c) d)
245 mm
254 mm
452 mm
425 mm
How do you call the flattened end of a shank, and intended to fit into a driving slot in the socket?
Handle
Tang
Relief
Tip
If a sleeve bearing has an outside diameter of 38.1 mm and a length of 50.8 mm, the wall thickness is 3/16 inch. The bearing is subjected to a radial load of 500 kg. What is the bearing pressure, in psi? a) b) c) d)
904 psi
409 psi
490 psi
940 psi
This material is the most popular alloy spring steel for conditions involving higher stresses than can be used with the high-carbon steels and for use where fatigue resistance and long endurance are needed; this is also good for shock and impact loads. a) b) c) d)
Chrome silicon
Chrome vanadium
hard-drawn wire
Oil-tempered wire
Determine the minimum whole depth of spur gear of 14.5o involute type with diametral pitch of 24 and circular pitch of 0.1309 inch.
0.09000 inch
0.08900 inch
0.0899 inch
0.089758 inch
. A parallel helical gear set was a 17-tooth pinion driving a 34-tooth gear. The pinion has a right-hand helix angle of 30o , a normal pressure angle of 20o , and a normal diametral pitch of 5 teeth/in. Find the axial circular pitches.
1.2566 inches/tooth
1.6625 inches/tooth
1.6526 inches/tooth
1.6256 inches/tooth
For an American Standard Screw Threads, what does 6-32 UNC designate?
Size 6, 32 threads per inch, coarse thread
6 inches basic diameter, 32 threads per inch, coarse thread
Size 6, 32 threads per inch, fine thread
32 inches basic diameter, 6 threads per inch, coarse thread
Determine the Poisson’s ratio of a material whose modulus of elasticity is 200 GPa and whose modulus of rigidity is 80 GPa. a) b) c) d)
0.33
0.25
0.38
0.22
A steel has a BHN = 300. What is its approximate ultimate strength in ksi?
300 ksi
150 ksi
75 ksi
200 ksi
If the angular deformation of a solid shaft should not to exceed 1o in a length of 1.8 m and the allowable shearing stress is 83 MMa, what is the diameter of the shaft? Assume that the shaft material has G = 77 x 106 kPa. a) b) c) d)
222.34 mm
234.22 mm
23.42 cm
24.22 cm
How do you call the process of producing the residual compressive stress of machine parts, which is performed by directing the a high velocity stream of hardened balls or pellets at the surface to be treated. a) b) c) d)
Nitriding
Shot blasting
Peening
Tempering
Determine the Hp lost when a collar is loaded with 2000 lb, rotates at 50 rpm, and has a coefficient of friction of 0.15. The outside diameter of the collar is 4 inches and the inside diameter is 2 inches.
0.7314 Hp
0.3714 Hp
0.4713 Hp
0.4371 Hp
. It is a process that produces residual compressive stress on the machine part, which uses a series of hammer blows on the surface. a) b) c) d)
Nitriding
Shot blasting
Peening
Tempering
Two shafts 3.6 m between centers carry pulleys 1.2 m in diameter and 0.91 m in diameter respectively, connected by a crossed belt. It is desired to put the belt on as an open belt. How long a piece must be cut of it? a) b) c) d)
303.3 mm
330 mm
333.0 mm
330.3 mm
It is a surface-hardening process for alloy steels in which the material is heated to 950 oF in a nitrogen atmosphere, typically ammonia gas, followed by slow cooling.
Quenching
Nitriding
Shot blasting
Peening
A 20-tooth motor sprocket, running at 1200 rpm, drives a blower at a speed ratio of 4:1. Using the largest permissible chain size and the largest permissible center distance of 80 pitches, what length of chain in pitches is required to connect the sprockets? a) b) c) d)
200 pitches
212 pitches
216 pitches
220 pitches
Which of the following gases is typically used in nitriding process of surface hardening?
Nitrogen gas
Carbon dioxide
Ammonia gas
Hydrogen gas
A 20-kW motor, running at 1200 rpm, drives a 400 mm diameter pulley at a belt tension ratio of 2.4. If the belt’s tight side tension is only 1200 N, determine the transmission efficiency.
87.97 %
84.58 %
85.66 %
86.55 %
A right-handed single-thread hardened-steel worm has a catalog rating of 2.25 kW at 650 rpm when meshed with a 48-tooth cast-steel gear. The axial pitch of the worm is 25 mm, normal pressure angle is 14.5o , and the pitch diameter of the worm is 100 mm. The coefficient of friction is 0.085. Determine the shafts center distance.
241 mm
142 mm
412 mm
124 mm
Which of the following is the benefit in using nitriding as a surfacehardening process for alloy steels?
Improvement of endurance strength, 50 % or more
Improvement of endurance strength, less than 50 %
Improvement of endurance strength, more than 50 %
80 % improvement on the endurance strength
. A 20o straight-tooth bevel pinion having 14 teeth and a diametral pitch of 6 teeth/inch drives a 42-tooth gear. The two shafts are at right angles and in the same plane. Find the pitch angle of the pinion.
18.4o
20o
14.5o
20.5o
A triple-thread worm has a lead angle of 17o and a pitch diameter of 2.2802 inches. Find the center distance when the worm is mated with a wheel of 48 teeth. a) b) c) d)
6.72 inches
7.26 inches
6.27 inches
7.62 inches
A double-thread worm has a pitch diameter of 3 inches. The wheel has 20 teeth and a pitch diameter of 5 inches. Find the gear helix angle. a) b) c) d)
4.69o
9.46o
6.49o
6.94o
A 36-tooth pinion turning at 300 rpm drives 120-tooth gear of 14.5o involute full depth pressure angle. Determine the rpm of the driven gear.
60 rpm
45 rpm
75 rpm
90 rpm
If two parallel shafts are connected by cylinders in pure rolling contact and turning in the same direction, and having a speed ratio of 2.75, what is the Center distance of the two shafts assuming that the diameter of the smaller cylinder is 22 cm?
18.25 cm
19.25 cm
20.25 cm
17.25 cm
In estimating the actual endurance strength of steel parts, one of the factors to be considered is the material factor, which of the following is the recommended material factor for cast steel? a) b) c) d)
0.70
0.80
0.75
1.0
. How do you call the level of stress that the part will be permitted to see under operating conditions?
Yield stress
Endurance stress
Design stress
Ultimate stress
Which of the following column formulas is applicable to cast iron columns?
Euler’s formula
J.B.Johnson’s formula
Secant formula
Straight line formula
. Which of the following ferrous metals has the lowest carbon content?
Carbon steel
Wrought iron
Cast iron
SAE 4140
Two extension coil springs are hooked in series that support a single weight of 100 kg. The first spring is rated at 4 kN/m and the other spring is rated at 6 kN/m. Determine the total deflection of the springs.
408.6 mm
486.0 mm
480.6 mm
460.8 mm
. If the ultimate shear strength of a steel plates is 42 000 psi, what force is necessary to punch a 0.75 inch diameter hole in a 0.625 inch thick plate? a) b) c) d)
61 850 lb
65 810 lb
61 580 lb
60 185 lb
If stiffness is the main criterion in selecting a material, which of the following is the most economical choice?
SAE 3130
SAE 1020
SAE 6150
AISI 301, ¼ hard stainless steel
Which of the following materials can easily be machined? a) b) c) d)
AISI C1020
AISI C1112
AISI C1030
AISI C1010
Wood is an ______ material; that is, its mechanical properties are unique and independent in three mutually perpendicular directions— longitudinal, radial, and tangential.
Isotopic
Anisotropic
Orthotropic
Any of these
A stepped torsion shaft has diameters of 16 mm and 12 mm and a fillet radius of 2 mm. The shaft is subjected to a torque of 12.5 N-m. Find the maximum induced stress caused by the fillet. Consider a stress concentration factor of 1.25.
36.84 MPaa
46.05 MPa
38.64 MPa
45.06 MPa
A steam engine that has a stroke of 12 inches has an overhung crank of 11 inches. The maximum tangential force, P, on the crank may be assumed as 75000 lb. Assuming an allowable stress in shear as 4400 psi, determine the crankshaft diameter.
4.77 inches
3.77 inches
2.77 inches
1.77 inches
The principal raw materials used in steelmaking are iron ore, coal, and __________.
Coke
Limestone
Slag
Flux
The steel part is heated to a temperature of 900–1150 degrees F in an atmosphere of ammonia gas and dissociated ammonia for an extended period of time that depends on the case depth desired.
Nitriding
Carburizing
Case hardening
Cyaniding
Determine the Hp lost when a collar is loaded with 2000 lb, rotates at 50 rpm, and has a coefficient of friction of 0.15. The outside diameter of the collar is 4 inches and the inside diameter is 2 inches. a) b) c) d)
0.7314 Hp
0.3714 Hp
0.4713 Hp
0.4371 Hp
The primary application of high-speed steels is to tools used for the working of metals __________.
That are too hard
at high cutting speeds
That are too soft
at slow cutting speeds
A parallel helical gear-set consists of a 19-tooth pinion driving a 57-teeth gear. The pinion has a left-hand helix angle of 20o , a normal pressure angle of 14½o , and a normal diametal pitch of 10 teeth/inch. If the pinion is to transmit 50 Hp at a speed of 1750 rpm. Determine the center distance of the two gears. a) b) c) d)
2.02 inches
6.06 inches
4.04 inches
2.06 inches
In gearing, this is the ratio of the arc of action to the circular pitch.
Speed ratio
Arc ratio
Contact ratio
Gear ratio
A single square thread power screw is to raise a load of 70 kN. The screw has a major diameter of 36 mm and a pitch of 6 mm. The coefficient of thread friction and collar friction are 0.13 and 0.10 respectively. If the collar mean diameter is 90 mm and the screw turns at 60 rpm, find the axial linear speed of the screw.
5 mm/s
6 mm/s
7 mm/s
5.5 mm/s
Flywheel arms are usually of elliptical cross-section, the strength of the arms should equal _________the strength of the shaft in torsion. a) b) c) d)
Three-fourths
One-half
Two-thirds
One-fourth
This alloy (nickel, iron, chromium, cobalt is a non-magnetic, corrosion resistant material suitable for sub-zero temperatures and temperatures up to about 750 degrees F., provided that torsional stresses are kept below 75,000 pounds per square inch. It is precipitation-hardened to produce hardnesses of 48 to 50 Rockwell C and is used in watch and instrument springs. a) b) c) d)
Elinvar
Monel
Inconel
Dynavar
To ensure an adequate factor of safety in the design of a shaft with standard keyway, the key width should be about:
One half of the shaft diameter
One fourth of the shaft diameter
One eighth of the shaft diameter
One third of the shaft diameter
What is the property of matter that causes it to resist any change in its motion or state of rest?
Momentum
Kinetic Energy
Inertia
Section modulus
This is defined as the cutting time to reach a predetermined wear, called the tool wear criterion.
Wear duration
Cycle time
Tool life
Life cycle
Which of the following G-codes refers to rapid traverse in CNC machining?
G00
G01
G02
G03
An acronym in CNC machining which means access of the machine operator to insert machining instructions directly into the NC machine control system via push buttons, pressure pads, knobs, or other arrangements.
FMS
FMC
CIM
MDI
The variable polarity plasma arc (VPPA) process was developed for welding metals that form an oxide skin, such as ___________. a) b) c) d)
Steel
Copper
Cast iron
Aluminum
Which of the following statements is NOT true? a) . b) c) d)
The terms “polishing” and “buffing” are sometimes applied to similar classes of work in different plants
Polishing is any operation performed with wheels having abrasive glued to the working surfaces
Buffing is done with wheels having the abrasive applied loosely
Polishing is not so harsh an operation as buffing, and it is commonly utilized to obtain very fine surfaces having a “grainless finish.”
If the steel is strongly deoxidized by the addition of deoxidizing elements, no gas is evolved, and the steel is technically called _______because it lies quietly in the molds. a) b) c) d)
Quenched
Annealed
Killed
Tempered
Stainless steels generally contain at least __ per cent chromium, with or without other elements
18
16
12
10
What grades of stainless steels are nonmagnetic in the annealed condition, although some may become slightly magnetic after cold working? a) b) c) d)
Ferritic grades
Austenitic grades
Martensitic grades
Any of these
These steels (SAE Steels 1006, 1008, 1010, 1015) are the lowest carbon steels of the plain carbon type, and are selected where ________ is the primary requisite of the user. a) b) c)
Strength
Cold formability
Ductility
Durability
Steel is heated to a temperature above the critical range, after which it is cooled in still air to produce a generally fine pearlite structure. The purpose is to promote uniformity of structure and properties after a hot-working operation such as forging or extrusion. What was the heat treatment involved? a) b) c) d)
Annealing
Normalizing
Tempering
Stress relieving
At certain speeds called the critical speeds, a rotating shaft will become dynamically unstable and the resulting vibrations and deflections can result in damage not only to the shaft but to the machine of which it is a part. At what percentage of the critical speed should a shaft be safely operated?c
Plus or minus 20%
Plus or minus 5 %
Plus or minus 10 %
Any of these
It is an acronym in machining. This process uses an electrode to remove metal from a workpiece by generating electric sparks between conducting surfaces. a) b) c) d)
MIG
GMAW
EDM
CNC
In die casting accurate parts made of steel, what shrinkage allowance in inches per inch is recommended? a) b) c) d)
0.011
0.022
0.033
0.044
This are gears used to connect shafts that are non-intersecting and non-parallel. They are a cross between spriral bevel gears and worm gears.
Helical gears
Hypoid gears
Planetary gears
Bevel gears
This is a type of seal used where some form of relative motion occurs between rigid parts of an assembly.a) b) c) d)
Gasket
Distorted seal
Vibratory seal
Dynamic seal
It is a lubrication for roller chains wherein the lubricant is supplied by a circulating pump capable of supplying the chain drive with a continuous flow of oil inside the chain loop evenly across the chain width and directly at the slack strand. a) b) c) d)
Oil stream lubrication
Bath lubrication
Drip lubrication
Recirculated lubrication
In manufacturing, this is the operation of cutting out flat area to some desired shape and is usually the first step in a series of operation. a) b) c) d)
Turning
Facing
Blanking
Finishing
An M-code which generally refers to start spindle rotation in a clockwise direction.
M03
M04
M05
M06
A final operation to improve the polish of a metal and to bring out the maximum luster
Finishing
Surface grinding
Broaching
Buffing
Machining operations with the proper application of a cutting fluid generally has the following attributes except: a) b) c) d)
Higher cutting speeds
Higher feed rates
Lengthened tool life
Higher cutting accuracy
A material of construction (only developed commercially in the late 1940’s concurrently with zirconium) offers the unique combination of wide ranging corrosion resistance, low density, and high strength. a) b) c) d)
Tungsten
Titanium
Vanadium
Molybdenum
Which of the following is the lightest of all structural metals? a) b) c) d)
Aluminum
Copper
Magnesium
Manganese
This process reduces internal stresses, caused by machining, cold working, or welding, by heating the steel to a temperature below the critical range and holding it there long enough to equalize the temperature throughout the piece. a) b) c) d)
Annealing
Normalizing
Tempering
Stress Relieving
A free-cutting steel has a higher ______ content than comparable carbon steels. a) b) c) d)
Sulfur
Cobalt
Nickel
Chromium
This property designates the steels resistance to the softening effect of elevated temperature.
Hot hardness
Machinability
Toughness
Elasticity
Use of hard solders, silver solders and smelter solders which have silver, copper, or nickel bases and have melting points above 800 degrees F is known as_______ a) b) c) d)
Soldering
Welding
Brazing
Any of these
In braking, the term backstop refers to a brake that is: a) b) c
Self locking in one direction
Self energizing
Self locking in both directions
Any of these
How do you call a fixed crane consisting of a supported vertical member from which extends a horizontal swinging arm carrying a trolley hoist or other hoisting mechanism?
Jib crane
Gantry crane
Overhead crane
Tower crane
This iron is also known as a ductile cast iron. How do you call this iron?
Malleable iron
Nodular cast iron
White cast iron
Gray cast iron
It is the ability to deform plastically to compensate for irregularities in bearing assembly. How do you call this? a) b) c) d)
Plasticity
Conformability
Embeddability
Elasticity
A material of construction (only developed commercially in the late 1940’s concurrently with zirconium) offers the unique combination of wide ranging corrosion resistance, low density, and high strength. a) b) c) d)
Titanium
Tungsten
Vanadium
Molybdenum
Newton’s law of motion that describes that if a force acts to change the state of motion of the body, the body offers a resistance equal and directly opposite to the force. a) b) c) d)
Second law
Third law
First law
Universal gravitation
These are steels most widely used of engineering materials. No other material offers comparable versatility for product design. a) b) c) d)
Wrought steels
Low carbon steels
Medium carbon steels
Tool steels
What is an element added to steel to improve its machinability? a) b) c) d)
Carbon
Sulfur
Cobalt
Chromium
Which of the following information is FALSE regarding steel that has increased carbon content? a) b) c) d)
Its strength is increased
Its BHN becomes greater
Its ductility is improved
Its % reduction or elongation is reduced
In manufacturing, what is the operation of cutting out flat area to some desired shape and is usually the first step in a series of operation?
Turning
Blanking
Facing
Finishing
This is a metal joining process which uses a non-ferrous filler metal with a melting point below that of the base metals but above 800F. How do you call this process?
Brazing
Arc welding
Soldering
Riveting
Rivet holes are made usually ____ inch larger in diameter than the nominal diameter of the rivet. a) b) c) d)
1/8
1/16
¼
1/32
Which of the following equations/formulas does not belong to the group? a) b) c) d)
Lame’s equation
Euler’s formula
J. B. Johnson’s equation
Secant formula
In CNC programming, which of the following G code commands is for dwell or rest?
G01
G04
G03
G02
In CNC programming, which of the following M code commands is for a tool change?
M06
M04
M03
M10
Which of the following is a material description referring to unique properties in three mutually perpendicular planes?
Isotropy
Anisotropy
Orthotropy
Isometry
The true stress-strain curve in a stress-stress diagram appears to be:
Lower than the engineering stress-strain curve
Higher than the engineering stress-strain curve
The same as the engineering stress strain curve
Symmetrical with the engineering stress-strain curve
This is a hardening treatment for steels having low carbon content.
Tempering
Case hardening
Normalizing
Anodizing
What is a manufacturing process used for the production of aluminum? a) b) c) d)
Forging
Extrusion
Blow molding
Injection molding
This refers to a loss of material from the interface of two metal surfaces that are in intimate contact. How do you call this?
Interfacing
Interference
Wear
Fretting corrosion
This is a type of fit that requires heating the hub to expand its inside diameter. What do you call this type of fit?
Expansion fit
Force fit
Shrink fit
Any of these
AFBMA is an acronym for an association involved in what machine elements?
Ball and roller bearings
Journal bearings
Flat belts and other belt types
Any type of gears
What is the general description for mild steel? a) b) c) d)
Medium carbon steel
Low carbon steel
High carbon steel
Cold rolled steel
Von Mises theory is the other term used for
Maximum principal stress theory
Octahedral shear-stress theory
Maximum shear-stress theory
Energy distortion theory
A type of key in which width and thickness are equal is called as:
Flat key
Square key
Pin key
Barth key
In the design of key, the typical hub lengths are in accordance with the following relation where D is shaft diameter. a) b) c) d)
1.25D to 2.4D
0.5D to 1.25D
2.4D to 3.5D
Depends on shaft diameter
A coupling that allows axial flexibility/movement in the operation. Made of alternate bolting of steel, leather, fabric and/or plastic material into two flanges.
Flexible disk coupling
Flexible toroidal spring coupling
Flexible Oldham coupling
Elastic material bonded coupling
It is a machine member that supports another part that rotates, slides, or oscillates in or on it.
Pulley
Key
Bearing
Shaft
It is a bearing that permits constrained relative motion of rigid parts; lubricant is generally inserted or supplied between the mating surfaces to reduce friction and wear, and to carry away the heat generated.
Sliding Contact Bearing
Rolling Contact Bearing
Thrust Bearing
Journal Bearing
These are surfaces that do not conform to each other very well as in the rolling-element bearings.
Conformal surfaces
Non-conformal surfaces
Sliding surfaces
Rolling surfaces
The study of lubrication, friction, and wear of moving or stationary parts is known as:
Lubrication
Tribology
Hydrodynamics
Hydrostatics
A bearing where surfaces are non-conformed and motion is primarily rolling; it composed of rolling elements interposed between an outer ring and inner ring.
Sliding-element bearing
Rolling-element bearing
Conformal surfaces bearing
Non-conformal surfaces bearing
In a straight bevel gear, how do you call the angle between an element on the pitch cone and an element on the face cone?
Face angle
Pitch angle
Addendum angle
Dedendum angle
It is a Grashof four-bar mechanism in which the shortest link is the frame or fixed link and the other two cranks completely rotate with their axes. How do you call this Grashof four-bar mechanism?
Drag-link mechanism
Crank-rocker mechanism
Double-rocker mechanism
Triple-rocker mechanism
“For a planar four-bar linkage, the sum of the shortest and longest lengths cannot be greater than the sum of the remaining two link lengths if there is to be a continuous relative rotation between two members.” How do you call the preceding statement?
Grubler’s Law
Coriolli’s Law
Grashof’s Law
Freudentein’s Law
Which of the following is not true for an instant center or centro of planar linkages?
Centro is a point common to two bodies having the same velocity in each.
Centro is a point in one body about which another body does not rotate.
Centro is a point in one body about which another body actually turns.
Centro is a point in one body about which another body tends to turn.
This is the most common work holding device of a shaper machine with the base graduated in degrees that make it possible to swivel any angle. What is this working device?
Shaper vise
Parallel bars and hold down bars
Lathe holder
Swivel head
This is a shaper operation, which is shaping the given stock and having the excess material remain with a tolerable allowance for finishing. How do you call this operation?
Roughing
Finishing
Angular cutting
Contouring
How do you call a cutting tool that has two or more cutting edges as in drill presses and milling machine cutters?
Grinder
Single-point cutting tool
Multi-point cutting tool
Two point cutting tool
This is the trade name for a patented alloy made up chiefly of cobalt, chromium, and tungsten in varying proportions. What is this trade name? a) b) c) d)
Stellite
Carboloy
Stainless steel
Copper
It is called as the transformation of concepts and ideas into useful machinery. What is this?
Design
Synthesis
Analysis
Theorem
This is a combination of mechanisms and other components that transforms, transmits, or uses energy, load, or motion for a specific purpose. How do you call this?
Mechanism
Engine
Machine
Linkage
It is defined as synergistic collection of machine elements; synergistic because as a design it represents an idea or concept greater than the sum of the individual pats. What is this system?
System of mechanisms
Mechanical system
Design system
Expert system
It may be defined as the displacement per length produced in a solid and as the result of stress. How do you call this?
Deformation
Elongation
Strain
Stress
What is the combination of applied normal and shear stresses that produces maximum principal normal stress or minimum principal normal stress, with a third principal stress between or equivalent to the extremes? a) b) c) d)
Principal shear stress
Principal normal stress
Maximum shear stress
Bending and shear stresses
How do you call a load that is applied transversely to longitudinal axis of member? a) b) c) d)
Combined loads
Concentrated load
Bending load
Distributed load
What is the ability of the material to absorb energy up to fracture?
Toughness
Rigidity
Resilience
Stiffness
What is the other term for the Maximum-Shear-Stress Theory, as a failure prediction theory?
von Mises criterion
Tresca yield criterion
Coulomb-Mohr theory
Modified Mohr theory
It is a failure prediction theory, which states that a part subjected to any combination of loads will fail (by yielding or fracturing) whenever the maximum shear stress exceeds a critical value. How do you call this failure prediction theory? a) b) c) d)
Distortion-energy theory
Maximum-shear-stress theory
Internal friction theory
Modified Mohr theory
This is a theory in cyclic and impact loading, which states that damage at any stress level, is proportional to number of cycles. What is this theory commonly called? a) b) c) d)
Miner’s Rule
Paris Power Law
Goodman Rule
Manson-Coffin Relationship
This is a lubrication where the load-carrying surfaces of the bearing are separated by a relatively thick film of lubricant, so as to prevent metal-to-metal contact; and where the stability of the film can be explained by the laws of fluid mechanics. How do you call this type of lubrication? a) b) c) d)
Hydrostatic lubrication
Hydrodynamic lubrication
Elastohydrodynamic lubrication
Boundary lubrication
How do call the speed at which a rotating shaft becomes dynamically unstable?
Normal speed
Variable speed
Critical speed
Average speed
How do you call a ball bearing with race containing pronounced groove for rolling elements? a) b) c) d)
Crown bearing
Conrad bearing
Angular-contact bearing
Cylindrical bearing
This is a machining process for producing internal straight cylindrical surface or profiles, with process characteristics and tooling similar to those for turning operations. What is this machining process?
Boring
Drilling
Reaming
Milling
What is a set of specification for parts, materials, or processes intended to achieve uniformity, efficiency, and a specified quality?
Code
Standard
Law
Theorem
This is a set of specifications for the analysis, design, manufacture, and construction of something; the purpose of which is to achieve a specified degree of safety, efficiency, and performance or quality. How do you call this set of specifications?
Code
Standard
Law
Theorem
How do call the size to which limits or deviations is assigned and is the same for both members of the fit; it is the exact theoretical size?
Nominal size
Basic size
Maximum size
Minimum size
What is the algebraic difference between a size and the corresponding basic size?
Tolerance
Allowance
Deviation
Limit
What is the difference between the maximum and minimum size limits of a part?
Allowance
Tolerance
Deviation
Basic size
This is used either for very accurate angular measurements or for locating work at a given angle; is used together with precision gage blocks. What is this?
Protractor
Compound rest
Sine bar
Micrometer
