PRONAR T028KM, Operator'S Manual

Page: 72 / 101

PRONAR T028KM PRONAR T028ML SECTION 5
5.10
Excessive wear of brake shoes is the condition in which the thickness of linings which are
glued or riveted to steel structures of brake shoes is smaller than the minimum value. This
condition is indicated by extended cylinder piston stroke. Check technical condition of brake
shoe linings through inspection openings (3) – figure (5.5).
5.2.7 MECHANICAL BRAKES ADJUSTMENT
Preliminary information
Considerable wear of brake shoe linings results in increased brake cylinder piston stroke and
worse braking efficiency.
TIP
Correct brake cylinder piston stroke should be within the range of 25 – 45 mm.
During braking, the brake cylinder piston stroke should be within the specified operating
range and the angle between brake cylinder piston and expander arm should be about 90° –
compare figure (5.7).
ATTENTION
Incorrectly adjusted brake may cause rubbing of brake shoes against brake
drums, which may lead to faster wear of brake linings and/or brake overheating.
Braking force decreases also when the operating angle of the brake cylinder rod (5) – figure
(5.6) in relation to the expander arm (1) is wrong. In order to obtain the optimum mechanical
operating angle, the cylinder piston fork (6) must be installed on the expander arm (1) in such
a manner as to ensure that the operating angle at full braking is about 90°.
TABLE 5.1 Operating data of pneumatic cylinder
NOMINAL CYLINDER
STROKE
L [mm]
MINIMUM CYLINDER
STROKE
L
MIN
[mm]
MAXIMUM CYLINDER
STROKE
L
MAX
[mm]
75 25 45