Disc wheels

A propeller fan consists of a propeller or disc wheel within a mounting ring or plate. The propeller fan is designed to move air from one enclosed space to another or from indoors to outdoors or vice versa in a wide range of volumes at low pressure. (The automatic type of shutter illustrated in the cutaway opposite is not a part of the propeller fan but is an auxiliary device to protect the fan when not operating by keeping out wind, rain, snow, and cold). 

Any cracks in welds attaching disc wheel disc to rim. 

Any welded regair other than disc to rim attachment on steel disc wheel(s) mounted on the steering axle. 

Disc wheels. These reduce the wind resistance usually encountered by spoked wheels. Heavier disc wheels also act like a flywheel and so conserve momentum. 

New iwiiifj hicgcles have disc wheels to reduce w/jfrf resi.strt cc. 

New racing bicijcles have disc wheels because/since/as this reduces wind resistance. 

New racing bicycles have disc wheels so that ivi/iri resistducc is reduced. 

Old bicycles have. spoked wheels, in contrast, the new bicycle has disc wheels. 

Disc Wheels All power-driven rotatable discs faced with abrasive material, artificial or natural, and used for grinding or polishing on the side of the assanbled disc. 

Grinding Wheels All power-driven rotatable grinding or abrasive wheels except disc wheels as defined in this standard consisting of abrasive particles held together by artificial or natural bonds and used for peripheral grinding. 

Horizontal Single-Double Disc Grinder A grinding machine carrying two power-driven, rotatable, coaxial horizontal spindles upon the inside ends of which are mounted abrasive disc wheels used for grinding two surfaces simultaueously. 

Horizontal Single-Spindle Disc Grinder A grinding machine carrying an abrasive disc wheel on one or both ends of a power-driven, rotatable single horizontal spindle. 

Vertical Spindle Disc Grinder A grinding machine having a vertical, rotatable power-driven spindle carrying a horizontal abrasive disc wheel. 

Loose, missing, broken, cracked, or stripped wheel fasteners that are ineffective as follows for 10 fastener positions - 3 anywhere or 2 adjacent for 8 fastener positions or less - 2 anywhere (this applies to both spoke and disc wheels). (393.205(c))... 

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