Chapter 30—Mechanical PM

MULTIPLE CHOICE

	1.	What is an early indication that a bearing may be overheating?
a.	solid or caked lubrication	c.	etched raceways	
b.	rust	d.	pitting	

	2.	What type of bearing should be used in a dirty environment?
a.	roller bearing	c.	sealed bearing	
b.	needle bearing	d.	plain bearing	

	3.	Rusting surfaces are an indication of ____.
a.	old age	c.	oxidation	
b.	rusting	d.	moisture	

	4.	Gearboxes contain _____ to keep the gears lubricated and cooled.
a.	grease	c.	padding material	
b.	oil	d.	straw	

	5.	What does it mean if the oil has a metallic look when you open a gearbox?
a.	bad seals	c.	worn gears	
b.	deteriorating bearings	d.	bad oil	

	6.	On inspection, it is noticed that a seal has a slight amount of leakage. For what type of seal would this be desirable?
a.	The O-ring	c.	The radial lip seal	
b.	The mechanical seal	d.	The packing seal	

	7.	When should a radial lip seal be replaced? Choose the best answer.
a.	When it is discolored	c.	Every 6 months	
b.	When it has nicks and/or small cuts	d.	Only when it is leaking	

	8.	What causes the tension members to break in a V-belt or a positive-drive belt?
a.	overloading	c.	old age	
b.	overheating	d.	stretching	

	9.	The pulley should be changed when the the V-belt has dropped ____ into the pulley.
a.	1/32 inch	c.	1/8 inch	
b.	1/16 inch	d.	1/2 inch	

	10.	What is compromised when a positive-drive belt begins to skip?
a.	tooth integrity	c.	positive traction	
b.	pulley performance	d.	belt integrity	

	11.	What is the leading cause of coupling wear?
a.	misalignment	c.	bad fillers	
b.	lack of attention	d.	overloading	

COMPLETION

	1.	Bearing failure is generally caused by a lack of ___________________ or overloading

	2.	The most common problem with chain drives is that the chains are not checked and ____________________ often enough.

	3.	The two most common types of couplings are ___________________ and flexible.

	4.	Failure of rigid couplings is usually indicated by a small pile of __________________ on the floor just below the coupling assembly.