design problems coaching

An ammonia compressor is driven by a 200kw motor. The compressor and the motor RPM are 380 and 1750, respectively. The small sheave has a pitch diameter of 152.4 mm. If the bolt to be used is standard C-120 (L = 122.9 in). Determine the center distance between sheaves.

Ans. 806 mm

A safety valve spring having a 9 and 0.5 coils has the ends squared and ground. The outside diameter of the coil is 115 mm and the wire is 13 mm. It has a free length of the wire to which this spring must be initially compressed to hold a boiler pressure of 1.38 Mpa on the seat of 32 mm diameter. Modulus of rigidity is taken as G=80 GN/m2.

Ans. 172

A single threaded trapezoidal metric thread has s a pitch of 4 mm, and a mean diameter of 18 mm.

Ans. 32.6 N-m

Determine the diameter of the stud bolt that are required to fasten down the cylinder head of a 203mm x 304mm gas engine.

Ans. 38.1

A single square thread power screw is to raise a load of 70 KN.

Ans. 12.526%

Find the horsepower required to drive a power screw lifting a load of 4000 lbs.

Ans. 4.395 hp

A flywheel has a mean diameter of 4 ft and is required to handle 2200 ft-lb of kinetic energy.

Ans. 334 lb

Find the rim thickness for a cast iron flywheel with a width of 200mm, a mean diameter of 1.2 in a normal operating speed of 300 rpm,

Ans. 28.25

A cast iron flywheel is rotated at a speed of 1200 rpm and having a mean rim radius of 1 foot.

Ans. 14, 700

A centrifugal pump is directly couple to a motor. The pump rating is 3, 600 liters per minute against a total head of 8 meters of water.

Ans. 10, 010.85

A 80 mm solid shaft is to be replaced with a hallow shaft of equal torsional strength.

Ans. 52.90%

A solid transmission shaft is 4 inches in diameter.

Ans. 122.940

A railroad track is laid at a temperature of 10 degree F with gaps of 0.01 feet between the ends of the rails.

Ans. 10409 psi

What load P which causes total deformation of 0.036 inch of a steel rack with has a cross section area of 4 sq. inches and a length of 5 ft.

Ans. 72, 000

What factor of safety is needed for a 2 inches diameter shaft with an ultimate strength of 50, 000 psi to transmit 40, 000 in-lb torque.

Ans. 2.62

A round steel shaft transmits 373 watts at 1800 rpm. The torsional deflection is not to exceed 1 deg in a length equal to 20 diameters.

Ans. 6.53 mm

A steel shaft operates at 186 rad/s and must handle 2 kw of power.

Ans. 11 mm

A 100 mm diameter solid shaft is to be replaced with a hollow shaft equally strong (torsion) and made of the same material.

Ans. 107.42 mm

If the weight of 6” diameter by 48” long SAE 1030 shafting is 174.5 kg then what will be the weight of chromium SAE 51416 of same size?

Ans. 347.96

A 50” diameter diamond saw blade is mounted on a pulley driven steel shaft

Ans. 687.55

A steel shaft transmits 40 hp at 1400 rpm.

Ans. 0.246 degrees/ foot

A multiple disc clutch of 10 steel disc and 9 bronze disc.

Ans. 39.566 hp

An engine of a motor vehicle with a wheel diameter of 712 mm develops 50 kw at 2000 rpm, the combined efficiency of the differential and transmission is 75% with an overall speed reduction of 25 is to 1. Determine the speed reduction of travel of the vehicle in km/ hr

Ans. 10. 74

An engine of a motor vehicle with a wheel diameter of 712 mm develops 50 kw at 2000 rpm combined efficiency of the differential and transmission is 75% with an over all speed reduction to 1. Determine the torque to be delivered by the clutch N-m

Ans. 239 N-m

The large diameter and face of the disk of a multiple disk clutch are 255mm and 25mm respectively.

Ans. 1, 688

A flange bolt coupling consist of eight steel 20mm diameter steel bolts spaced evenly around a bolt circle 300mm in diameter.

Ans. 40054 KPa

A flange coupling is to be designed, using 25 mm diameter bolts at a distance of 152 mm from the center of the shaft.

Ans. 5

Warwick screw….

Ans. 140.8Ans. 4.418

Notch Sensitivity….

Ans. 0.25