303.1 Flashcards
Which of the following factors affects the power transmitted by a belt?
Friction force applied by the belt and speed of the belt
Generally, the pitch diameter of a V-belt sheave is _____ the outside diameter
Less than
Among conventional V-belts, the narrowest is designated _____ and the widest is designated _______
A, E
The advantage of using a group belt instead of multiple belts is that the group is
more uniform
Because of their movable side flanges, spring-loaded adjustable sheaves require
Lubrication
Among the advantages of chain drives over belt drives is the fact that chain drives
are more efficient
Roller chains include the following parts:
roller links, pin links, rollers, busnings
Offset roller chain differs from standard roller chain in that the sidebars are ______ on one end of each link.
Closer together
A chain sprocket with a hub on both sides is a Type sprocket. A sprocket with a hub on only one side is a Type sprocket
C, B
When you install a roller chain, proper procedure includes
installing the chain with tension on the driving side only
The working depth of a gear is the distance a gear tooth
extends into the space between the teeth of the mating gear
Calculate the diametral pitch of the gear described below
2.04
The advantages of helical gears over spur gears include
smooth action
Herringbone gears differ from double-cut helical gears in that they (have)
no gap between the two sets of teeth
The axial pitch of a worm gear is the linear distance
between the screw threads
The main purpose of a miter-gear box is to change the _____ Its gear ratio is typically about ______ to one
direction of motion; one
The main steps in installing a new foot-mounted gear drive include
aligning the equipment
The mechanical power of a gear drive is based on the ____ of the gear drive.
speed and torque limit
The service factor for a gear drive depends in part on the
Duty cycle
In parallel-shaft gear drives, oil is commonly provided to the gears by means of
splash lubrication and pressurized feed
The most important factors in selecting an adjustable-speed drive include the units ____.
maximum power, speed required, and speed range
As you force together the flanges on the input sheave of an adjustable-speed belt drive while it is running, the flanges on the output sheave move _____ and the output shaft sleeve _____
farther apart; increases
An adjustable-speed drive can be controlled by a(n)
Gear mechanism, electric motor, or pneumatic piston
The belts used in adjustable-speed drives resemble ______ belts. In drives that use chain, the chain is similar to a ____ chain
Timing; leaf
in a roller-type adjustable-speed drive, the rollers have a _____ shape. Changes in speed are accomplisned by changing the _____ of the roller
conical, axial position
To align a new motor with an existing pump using the reverse indicator method, you mount the dial indicator(s) on the coupling flange(s) located on (the)
Both; opposite
When aligning three machines, you can align two of them to the third, unless doing so would require
lowering one or both below the support base
To align a new motor with an existing pump using the face-rim indicator method, you mount the dial indicator(s) on the coupling flange(s) located on (the)
only one, opposite
When aligning two machines joined by a long shaft, you use _____ dial indicators, which you mount on (the) ______
two, opposite coupling flanges
What are the advantages of laser alignment equipment over dial indicators?
Easier, faster, more accurate alignment
The two major classifications of jaw couplings are the _____ jaw couplings.
flexible and rigid
The advantages of a chain coupling include the fact that the chain
can be replaced without disconnecting the coupling hubs
If an overload occurs in a machine driven by a shear-pin coupling, the
Pins break
The special teatures of limited-end-float couplings include the
Thrust plate
spacer couplings provide certain advantages over ordinary couplings, including the fact that they
simplify the process of disconnecting a driving shaft from the driven shaft
The purposes or a clutch include
allowing one device to either be connected to another or to run independently
When a friction clutch operates, a
_____ forces the _____
shifting device, plates together or apart
An overrunning clutch is useful in equipment where the driven machine might need to
Run faster than the motor
An electric clutch should be used with a load that must
start and stop frequently
In a single-impeller fluid clutch, motion is directly transmitted from the drive shaft in which sequence?
Impeller, fluid, clutch housing
