Polyurethane Lagging

DESCRIPTION

Polyurethane lagging is used to increase service life of non drive pulleys. Polyurethane’s extreme abrasion resistance combined with it’s low coefficient of friction provide a solution to applications with premature wear when there’s a requirement for no risk of damage to the belt cover. Polyurethane is good for applications with carry back problems as it is slippery resisting material buld up. Polyurethane lagging is specially engineered moulding thermoplastic polyurethane inserts onto a rubber backing layer.

APPLICATION

Polyurethane lagging shall be specified on non drive pulleys when:

  • There’s a requirement for higher abrasion resistance than what achieved with rubber laggings.
  • In applications where there’s slippage between the conveyor belt and the lagging surface, such as on bend pulleys and non
  • drive pulleys on turnover conveyors. It’s low coefficient of friction make polyurethane lagging kind to the belt bottom cover.
  • When there’s buildup of material between the belt and the lagging.

DESIGN

Elastotec polyurethane lagging is 250 mm wide to ensure easy handling and application. It is supplied in long roll lengths that fit on standard sized pallets to eliminate waste and for cost effective transportation and storage. It can be supplied in thicknesses from 10 mm to 20 mm.

KEY FEATURES AND BENEFITS

Highly abrasion resistant polyurethane inserts prevent wear on pulley shell ans offers positive dirt release and
shedding.
Precision moulded strip with optimum polyurethane properties.
Supplied in strip form 250 mm wide for easy hadeling.
Strips packed in plastic film to preserve buffed bonding layer ready for application.
Coloured TPU insterts.
Low coefficient of froction difficult to stick to, resists buld up and is kind to belt cover.

ADHESION TO PULLEY

Elastotec polyurethane lagging can be applied to pulleys by cold bonding or by hot vulcanisation.

Elastotec cold bonding polyurethane lagging

Elastotec cold bonding polyurethane lagging is supplied with the CN buffed bonding layer and packed in plastic to protect and keep the CN bonding layer fresh and free from contamination until it is applied to the pulley.

To achieve a rubber tear bond, Elastotec cold bonding polyurethane lagging should be applied using Elastotec metal Primer 2205 and Elastotec cold bonding adhesive. These have been formulated to contain ingredients that chemically interlock with components in the CN bonding layer. When used together this is like a “chemical velcro” that makes the interface between the various layers stronger than the CN bonding layer.

Cold bonded polyurethane lagging applied by an Elastotec approved applicator to the requirements of the Elastotec application procedure will provide reliable adhesion levels that exceed 12 N/mm.

Elastotec hot vulcanising polyurethane lagging

Elastotec hot vulcanising polyurethane lagging is supplied with a 1.2mm thick uncured rubber layer applied to the back and sides of the lagging.

Hot vulcanising lagging is supplied packed in plastic to protect and keep the uncured bonding layer fresh and free from contamination until it’s applied to the pulley.

Elastotec provides detailed application procedures and on site training for approved applicators. Application by an Elastotec approved applicator will guarantee a 100% rubber tear bond between the lagging and the pulley shell with typical adhesion values exceeding 20 N/mm.

RUBBER SPECIFICATIONS

STANDARD
Polymer SBR/BR
Tensile strength (Mpa) 18
% Elongation min 550%
Hardness (shore A) 65+/5
Abrasion resistance max vol. loss
(DIN 53516 Method B non rotating)
70mm3
FRAS – MDG 3608 N/A
Heat ageing (Property change after 100C 70 hs) Tensile strength < 10% Elongation < 10% Hardness < 3 points
Continuous operating temperature 40/+70C

RUBBER SPECIFICATIONS

Tensile strength (Mpa) 30 (4,350 psi)
% Elongation min 550%
Hardness (shore A) 85+/5
Abrasion resistance max vol. loss
(DIN 53516 Method B non rotating)
35mm3
FRAS – MDG 3608 N/A
Heat ageing (Property change after 100C 70 hs) Tensile strength < 10% Elongation < 10% Hardness < 3 points
Continuous operating temperature 40/+70C
Adhesion to rubber (MPa) 6.0 min (100% rubber tear)