EATON
WCB11070.1
Brake Assemblies Installation, Operation and Maintenance Manual
E-CLCL-II015-E
December 2016
7
WCBD Brake Assemblies
1.0 INTRODUCTION
Throughout this manual there are a number of
HAZARD WARNINGS that must be read and
adhered to in order to prevent possible personal
injury and/or damage to the equipment. Three signal
words "DANGER", "WARNING", and "CAUTION" are
used to indicate the severity of the hazard, and are
preceded by the safety alert symbol .
Danger
Denotes the most serious injury hazard, and is
used when serious injury or death WILL result from
misuse or failure to follow specific instructions.
Warning
Used when serious injury or death MAY result from
misuse or failure to follow specific instructions.
Caution
Used when injury or product/equipment damage
may result from misuse or failure to follow
specific instructions.
It is the responsibility and the duty of all personnel
involved in the installation, operation and
maintenance of the equipment on which this device
is used to fully understand
Danger
,
Warning
,
and
Caution
procedures by which hazards are to be avoided.
1.1 Description
1.1.1 The Airflex WCBD brake assembly is identical to the
Airflex WCB2 tensioner/brake's with the exception of
a dual piston and cylinder that is also referred to as
the "power head assembly". This manual describes
the unique operation and maintenance features
associated with the dual chambered power head,
and is an WCBD brake assemblies addendum to the
manual for the basic WCB2 tensioner/brake that
has a single chambered piston and cylinder.
This manual should be used in conjunction with
Eaton manual WCB 11070 for installation, operation
and maintenance of any WCBD brake assemblies.
Refer to Eaton manual WCB 11070 for all functions
and parameters of the WCBD that are not specific to
the power head subassembly, such as friction disc
and wear plate maintenance.
1.2
How It Works
1.2.1 Referring to Figure 1, the operation of the
Airflex WCBD brake assembly is identical to that of
the Airflex WCB2 tensioner/brake with the exception
of the dual chambered piston/cylinder power head
assembly. In the WCBD brake assembly, air pressure
is applied to either the inner, outer, or both sets of
the ports in the dual cylinder (19), causing the dual
piston (33) and pressure plate assembly (13) to move
towards the mounting flange, compressing the
release springs. As the applied pressure to either or
both of pressure chambers increases, the friction
disc(s) are clamped between the pressure plate and
mounting flange, stopping or controlling the shaft
that the discs are mounted upon. Modulation of air
pressure then controls applied torque of the WCBD
brake assembly. The inner cylinder/piston chamber
area of the power head is referred to as the small
cylinder/piston, and the outer cylinder/piston chamber
area is referred to as the large cylinder/piston.
Refer to Section 1.2 of Eaton manual WCB 11070 for
additional details of operation.
1.3
WCB2 versus WCBD
1.3.1 The WCBD dual piston/cylinder power head offers
more precise tensioning control than the WCB2
tensioner/brake by dividing the standard WCB2
tensioner/brake piston/cylinder into a small and
large section. This provides the ability to improve
fine modulation of clamping pressure on the brake
discs and improved control over our standard single
chamber design. For very light tensioning loads, the
small piston can be used solely, with no pressure
applied to the large piston. For larger tensioning
loads, the large piston can be used solely, with no
pressure applied to the small piston. For the largest
tensioning loads, both pistons can be used together.
The combined area of the small and large piston/
cylinder power head of the WCBD brake assembly
is equal to the area of the WCB2 tensioner/brake's
single piston/cylinder. In this way, the maximum
applied torque for both styles of brakes is the same.
