EATON
WCB11076.1 WCBD Brake Assemblies with ORB Coolant Ports Installation, Operation and Maintenance Manual October 2014
6
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 Caution
the 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 11076 for installation, operation and
maintenance of any WCBD brake assemblies. Refer
to Eaton manual WCB 11076 for all functions and
parameters of the WCBD brake assembly that are
not specific to the power head subassembly, such as
friction disc assembly 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 11076 for
additional details of operation.
1.1.4 All WCBD brake assemblies referred to in this IOM
will have SAE O-ring Boss (ORB) ports for the coolant
inlets and outlets. These ports utilize a straight thread
and an O-ring for sealing versus the NPT tapered
thread used previously and referred to in IOM
WCB 11070. The ORB ports provide superior sealing
properties and reduce the risk of damage to the
WCBD brake assembly during fitting installation.
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 friction disc
assemblies 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 WCB
brake assemblies are the same.
WCBD Brake Assemblies with ORB Coolant Ports
