MDSP Inhouse Set 5 Review: Bearings, Flywheels, Springs, and Drives

Vocabulary-style flashcards defining key materials, designations, failure modes, and mechanical properties of power transmission and spring components.

ASTM A228

The ASTM designation specified for Music Wire used in precision compression springs.

ASTM A401

The ASTM code representing Chrome Silicon spring material used for heavy-duty valve springs.

ASTM A229

The ASTM specification for Oil-Tempered Wire spring material.

ASTM A232

The ASTM specification for Chrome Vanadium spring steel commonly used in fatigue-resistant applications.

Polygonal action

The phenomenon that causes slight cyclic variation in the speed of the driven sprocket of a roller chain transmission.

Wahl factor

A factor considered when calculating stress in a closed coil helical spring to account for curvature and stress augmentation effects.

Angle of wrap

The angle subtended by the belt while in contact with the pulley.

Oil stream lubrication

A type of roller chain lubrication where a circulating pump supplies a continuous flow of oil inside the chain loop across the chain width.

Petroff's equation

An equation for lightly loaded journal bearings where the coefficient of friction is directly proportional to lubricant viscosity.

Thin film bearing

A bearing where the surfaces of the journal and the bearing are partially separated by a film of lubricant and there is partial metal to metal contact.

Hydrodynamic lubrication

A lubrication condition requiring relative motion between the journal and bearing surfaces and a wedge-shaped clearance space.

Slip

The relative motion between the belt and pulley surface in belt drives.

Concentric springs

Springs used to achieve greater load carrying capacity within a given space, achieve a fail-safe system, or eliminate surge.

PV rating

The design parameter that should be checked first for a sleeve bearing operating without continuous lubrication.

Rolling-contact fatigue

The most likely cause of numerous shallow pits observed on bearing raceways after several thousand hours of service.

Bearing 410

A bearing designation indicating a heavy series with a bore diameter of $50\,mm$.

Moment of inertia

The flywheel property that primarily allows it to smooth speed variations during fluctuating torque.

Bursting of the rim

The failure mode most likely to occur if a cast-iron flywheel's rotational speed is increased beyond its maximum allowable rim speed.

Torsional shear stress

The type of stress induced in helical compression spring wire when subjected to an axial compressive force.

Windage losses

The primary reason modern flywheel energy storage systems operate in a vacuum chamber is to reduce these losses.

Square of the rim velocity

The factor to which the tensile stress produced in a flywheel rim due to centrifugal force is directly proportional.

Chain pitch

The dimension commonly checked during inspection to determine if excessive wear has occurred in a roller chain.