Return rollers

Return rollers

"Return rollers" are the idler rollers that are installed in the lower run of the belt conveyor and only carry the empty conveyor belt. 
Because they belong to a belt conveyor, all idler rollers of a belt conveyor can by referred to collectively as " conveyor belt rollers ". The return roller is therefore a type of conveyor belt roller.

In belt conveyors for bulk material handling the return rollers are usually fitted with support rings. Why do return rollers need support rings and why do we prefer to use polyurethane support rings? - You can find out here.

Detailed information to the dimensions of the idler rollers can be found in the chapter "Dimensions and designs".

Comparison of the quality classes of return rollers

We have defined three quality classes ("Compact", "Compact Plus" and "Premium"), which we recommend as the optimum solution depending on the application. Each quality class corresponds to the type of operating conditions on site and the requirements on the idler rollers.

Quality class
Roller tube
Tube	Welded cold-sized steel tubes acc. to EN 10305-3	Welded cold-sized steel tubes acc. to EN 10305-3; with restricted tolerances (Küpper Standard)	Welded cold-sized steel tubes acc. to EN 10305-3; with restricted tolerances (Küpper Standard)
Materials	Steel S235JR acc. to EN 10025-2	Steel S235JR acc. to EN 10025-2	Steel S235JR acc. to EN 10025-2
Bearing housing
Type	Deep-drawn part	Forged or cast part	Forged part
Materials	Steel DD13 acc. to EN 10111	Steel C15 acc. to EN 10267-2 or S235JR acc. to EN 10025-2 or gray cast iron EN-GJL-200 acc. to EN 1561	Steel C15 acc. to EN 10267-2 or S235JR acc. to EN 10025-2
Bearing seat	IT7	IT7	IT7
Shaft
Type	Solid	Solid or bending-resistant hollow shaft	Solid or bending-resistant hollow shaft
Materials	Round bar steel acc. to EN 10277	Round bar steel acc. to EN 10083-2 / Tube acc. to EN 10305-3	Round bar steel acc. to EN 10083-2 / Tube acc. to EN 10305-3
Bearing seat	IT9	IT6	IT6
Bearing
Make	AKT	AKT	AKT
Bearing type	Deep-groove ball bearing	Deep-groove ball bearing	Deep-groove ball bearing
Bearing sizes	6204 - 6306	6306 - 6312	6306 - 6312
Sealing	2Z	2Z	2Z
Bearing clearance	C4	C4	C4H
Tolerance classes	P0	P0	P5
Cage	Plastic cage	Plastic cage	Plastic cage
Greasing	50 - 60% of bearing´s free internal volume	50 - 60% of bearing´s free internal volume	Customized solutions
Sealing
Seal type	QLR hybrid seal	QLR hybrid seal	QLR hybrid seal
Support rings / Coating
Type	Support rings	Support rings or special 4-shapes support rings	Casted PU-coating
Material	Rubber, alternatively PU	PU	PU