Products Catalog
WCB elements are disc type, externally cooled units. They are designed to absorb and dissipate the thermal loads associated with the most severe clutch and brake applications. The WCB friction couple was developed specifically for continuous slip service and has a dynamic coefficient of friction that is greater than its static coefficient of friction. Also available, special high coefficient linings, which provide 50% higher torque than standard friction linings and provide a 1:1 dynamic to static torque ratio. Element construction and operation is illustrated. Pressurizing the cylinder causes the piston to clamp the friction disc between the water jackets. Heat generated at the friction interface is quickly transferred to the circulating coolant. Element sizes are indicated by the number of friction discs and the disc diameter in inches. For instance, size 224WCB has two (2) friction discs 24 inches in diameter.
Unit of Measure



N/A 348WCB

Dimension D24

N/A 1.48 in38 mm

Dimension D25

N/A 2.70 in69 mm

Dimension D43

N/A 5.80 in147 mm
Dimension G1 N/A 56.50 in1435.0 mm

Number of Bolt Holes H3

N/A 16

Bolt Hole Size H3

N/A 1 3/8-6
Bolt Circle Diameter H32 N/A 58.688 in1490.7 mm

Dimension H10

N/A 25.19 in640 mm

Dimension J1

N/A 23.00 in584 mm
Dimension J23 N/A 57.09 in1450 mm

Number H4

N/A 3

Size H4

N/A 3/4-10 in3/4-10 mm

Bolt Circle H4

N/A 24.500 in622.3 mm

Single Piston Size

N/A 1-11.5

Piston Inlet Bolt Circle Diameter

N/A 41.500 in1054.1 mm

Minimum Bore Size

N/A 10.250 in260 mm

Maximum Bore Size

N/A 16.81 in427 mm

Dimension D

N/A 30.70 in780 mm

Dimension D1

N/A 16.75 in425 mm

Dimension D2

N/A 25.71 in653 mm
Number of Coolant Ports (O)4 N/A 12
Coolant Port Thread Size5 N/A 1 1/4 SAE ORB

Gear Part Number

N/A 416688
Dynamic Torque Rating6 N/A 2058000 lb-in @ 80 psi 232523 Nm @ 5.5 bar
Thermal Rating7 N/A 3900 hp2908 kW
Water Flow8 N/A 390 gpm14763 dm³/min
Maximum Slip Speed9 N/A 360 rpm
Maximum Freewheeling Speed10 N/A 600

Housing (Weight)

N/A 6378 lb2893 kg

Disc & Gear (Weight)

N/A 2383 1081

Disc & Gear (Inertia)

N/A 186.85 4434

Housing (Inertia)

N/A 20398 lb·ft²859.59 kg·m²

Water Volume

N/A 2100 in³34.4 dm³


N/A Eaton-Airflex


N/A Air Applied

Where Used


  • Drilling rigs
  • Dynamometer
  • Logging equipment
  • Marine mooring systems
  • Slip clutches
  • Tension brakes
  • Unwind stands


N/A Patented piston design
Single or dual piston provides wider range of applied tension with greater control.

Drop in powerhead package
Standard single piston elements can be retrofitted with a dual piston powerhead to provide increased control.

Split wear spacers
The split wear spacers allow for wear adjustment without disassembly of the brake to minimize downtime and maintenance costs.

Unique friction couple
A specially formulated friction material, interfacing with a copper alloy surface, eliminates the stick-slip characteristic associated with ordinary frictional devices.

Rapid heat dissipation
The copper interface conducts heat rapidly to the circulating coolant.

Open or closed loop coolant systems
The element works equally well with open or closed loop circulating systems. On mobile equipment, the engine’s cooling system can be tapped to provide coolant to the element.

Optional corrosion protection
For marine environment applications, protective coatings are available to minimize corrosion.


N/A 1.96 in (50 mm) for 148WCB
1.75 in (44 mm) for 248WCB
1.75 in (44 mm) for 348WCB
1.75 in (44 mm) for 448WCB
Basic part number only. Order gear separately.

  • 1 Tolerance Sizes 8WCB thru 24WCB
    +0.000/-0.003 (+0.00/-0.08)
    36WCB +0.000/-0.005 (+0.00/-0.13)
    48WCB +0.000/-0.005 (+0.00/-0.13)
  • 2 American National Standard for Unified Screw Threads
  • 3 Maximum diameter of "as cast" surfaces
  • 4 American National Pipe Thread
  • 5 American National Pipe Thread
  • 6 Exact torque rating is dependent upon applied pressure. Maximum allowable pressure is 150 psi (10.3 bar).
  • 7 Exact torque rating is dependent upon applied pressure. Maximum allowable pressure is 150 psi (10,3 bar).maximum allowable outlettemperatures are 150ºF (65ºC) for fresh water; 165ºF (74ºC) for 70/30 and 60/40 water glycol mixes; and 170ºF (77ºC) for 50/50 water glycol mixes.
  • 8 To insure proper cooling, inlet port must be at the six o’clock position. Flow rates shown are for fresh water, flow rates for water glycol mixes must increase to achieve the ratings in the Thermal Rating column. Maximum allowable inlet pressure - 65 psi
  • 9 Based upon a continuous slip velocity of 4500 fpm (22.9 mps).
  • 10 Maximum freewheeling velocity is 7500 fpm (38.1 mps).