USPS 955 EXAM QUESTIONS WITH CORRECT ANSWERS LATEST UPDATE 2026

USPS 955 EXAM QUESTIONS WITH CORRECT ANSWERS LATEST UPDATE 2026 Which one of the following CANNOT be used as self-lubricating bushings? - Answers Sleeved bushings consist of metal, plastic, or reinforced fibers composites sleeves that reduce noise and vibrations by reducing the friction between moving mechanical parts. Oil (lubricants) foaming in gear mechanism is caused by: - Answers Contamination of lubricants with water Which are the three main factors to consider when choosing a lubricant? - Answers Temperature, workload, speed of moving parts The benefit/benefits of dynamic balancing are: - Answers Low vibrations, low noise, and higher bearing life ____________ roller bearings are available in cylindrical, barrel and taper shaped rollers. - Answers staggered When pressing a bearing into the housing, you should press against _________. - Answers the outer race only The purpose of a cylindrical roller bearing is to _________. - Answers Contain redial motion of the shaft The three basic shapes of roller bearings are: - Answers cylindrical, barrel, and tapered The purpose of a thrust bearing is to: - Answers Contain axial motion of the shaft _____________ cause overheating in the bearing and reduces the bearing life. - Answers insufficient lubrication and speed In order to remove a bearing from a steel shaft, ___________ can be used without damaging the bearing or the shaft. - Answers Dry ice and liquid nitrogen ____________ load is acting on the plane of the bearings' axis of rotation. - Answers Axial Which of the following statements is true? - Answers Zero-film are sliding bearing which are lubrication-free The characteristic number of the bearing is given by: Z=absolute viscosity of the lubricant, N= speed of journal, p=bearing pressure - Answers ZN/p Also called eccentrically loaded bearing is: - Answers Offset bearing Reducing noise from sprockets and chain can be done by: - Answers Choosing sprockets with more teeth, using a lighter chain, lubricating the bottom of the sprocket tooth What is the advantage of bushing? - Answers Self-lubricating, less noise, less vibration Which of the following lubrication system is used in two stroke engines? - Answers Mist system Thrust ball bearing are used to __________. - Answers Counteract axial force Which one of the following CANNOT be used as self-lubricating bushings? - Answers Sleeved bushings consist of metal, plastic, or reinforced fibers composites sleeves that reduce noise and vibrations by reducing the friction between moving mechanical parts. The throwout bearing and the spring diaphragm in a clutch are connected: - Answers When the clutch pedal is pressed Bearing failure in motors can be caused due to wrong selection of bearings. A motor mounted horizontally or vertically needs _____________ types of bearings. - Answers different For a journal bearing design, the clearance ratio ("clearance") should be approximately considered as: - Answers 0.0010 Select a bearing to sustain axial as well as radial loads: - Answers Tapered roller bearing Which of the following can provide bi-directional thrust load? - Answers Thrust ball bearings Hydrostatic bearing usually use __________ as lubricant. - Answers Oil Oil whirl in journal bearing can be prevented by ________ - Answers Providing an obstacle to the whirling fluid or providing the stabilized loading are used to avoid whirls Which of the following wear type occurs the least in a bearing when used in a turbine? - Answers Corrosion V-belts are superior to flat belts because ________. - Answers The belt does not slip away and slip off from the pulley A v-belt drive has just had its belts replaced. What must be checked/done as a first precaution before running the drive? - Answers The belts are placed over the sheaves and in the grooves without forcing Which one is NOT true for under tension belts: - Answers Reduce bearing and belt life Which of the following is NOT a procedure for surface and edge wear inspection of a belt? - Answers Confirm that belt can be moved laterally of the drive/idle shaft Considering the power transmission through V-belt, which one is not correct? V-belts are used at the high-speed end. used at the low-speed end. of standard lengths. of standardized angles. - Answers 2 The cause of creep in belts is due to: - Answers Unequal tension in tight and slack side of the belt The inner diameter (ID) and the outer diameter (OD) of a clutch plate pair are 100 mm and 200 mm respectively. The operating force of the clutch is 23.6 kN. Calculate the permissible intensity of pressure (N/mm2). - Answers 1.5 In a two-sprocket chain mechanism, to achieve 150 rpm at the smaller sprocket when the bigger sprocket (50 teeth) rotates at 50 rpm, what should be the number of teeth of the smaller sprocket? - Answers 16 The X gear has 5 teeth and is connected to the motor. The Y gear has 20 teeth and is an intermediate idler gear. The Z gear has 30 teeth and is connected to the roller. If the roller's required speed is 50 rpm, what should be the motor's rotating speed? - Answers 300 Gear A has 30 teeth and rotates at 30 rpm. Gear B has 15 teeth. How many rpm will gear B rotate when driven by the same driving gear? - Answers 60 The distance between two sprocket teeth is called _______. - Answers Pitch What is the output speed of the gearbox shaft if the input speed is 200 revolutions per second? The gear ratio is 10. - Answers 33.33 rpm Before the piston is removed, we must remove the: - Answers Piston ring How much input pressure is required in order to create a force of 200 lbs. in a piston whose blank side is 10 sq. inches? - Answers 20 psi Solenoids that are found on directional valves and are used in pneumatic circuits are ____________. - Answers Actuators As compared to hydraulic cylinders of the same strength, compressed air cylinders provide ______________ force. - Answers Smaller For a moderate cylinder speed of a pneumatic cylinder, the cross-section area of the piping should be _________ to/than the cylinder output port. - Answers Equal