The Rowland Company
The Rowland Company
4900 North 20th St.
Philadelphia, PA 19144
Toll Free: (800) 925-8824
Phone: (215) 455-4900
Fax: (215) 455-8888
Email: rowland@rowland2.com
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Model DBA brakes are spring applied, pressure released, disc style brakes. They develop equal torque in either direction of rotation. Their torque and thermal capacities allow them to be used in the most demanding applications.

Brake construction and operation is shown in the figure. Pressurizing the brake compresses the brake springs and withdraws the clamping plates from the brake discs. Standard brakes are furnished with either one or two discs, which are free to move axially.

Model DBA uses a rubber diaphragm to form the releasing pressure chamber and to serve as the releasing piston. Brake friction material is attached to stationary components. Brake discs are either solid or ventilated. The disc type is indicated by an S for solid, or V, for ventilated, in the brake model designation. Solid discs are used in applications requiring a heat sink and/or where engagement is infrequent. Ventilated discs are recommended for cyclic applications.

Torque ratings listed are for brakes with a standard compliment of springs. The quantity of springs can be varied to customize the torque of the brake to suit a particular application. Consult the factory for brake torque of units with nonstandard spring configurations.

Brake sizes are indicated by the number of brake discs and the disc diameter in inches. For instance, size 229DBA has two discs 29 inches in diameter.
Unit of Measure

Features

N/A Large friction area.
Allows brakes to absorb and dissipate high energy loads associated with high cyclic and high inertia stops.

Minimal adjustment required for lining wear.
Single disc units require no wear adjustment and dual disc units require only one wear adjustment during the long life of the friction material.

Where Used

N/A

  • Can making machines
  • Draglines
  • Power shovels
  • Conveyors
  • Power presses

Specifications

Model

 N/A 121DBAS

Dimension D25

 N/A 2.00 in51 mm

Dimension H

 N/A 3.000 in584 mm

Dimension H11

 N/A 21.00 in533 mm

Dimension H13

 N/A 12.12 in308 mm

Dimension H16

 N/A 7.62 in194 mm
Dimension G1 N/A 26.498 in673.9 mm

Dimension L

 N/A 1.06 in27 mm

Dimension O2

 N/A 1-11 1/2 NPT

Minimum Bore

 N/A 2.88 in73 mm

Maximum Bore

 N/A 5.75 in146 mm

Dimension D

 N/A 11.33 in288 mm

Dimension D7

 N/A 5.62 in143 mm

Dimension D29

 N/A 2.00 in51 mm
Dynamic Torque Rating2 N/A 69800 lb·in7890 Nm

Disc & Gear (Inertia)

 N/A 42 lb·ft²1.76 kg·m²

Disc & Gear (Weight)

 N/A 130 lb59 kg

Housing (Weight)

 N/A 610 lb276 kg

Minimum Releasing Pressure

 N/A 85 psi5.9 bar

Maximum Speed

 N/A 1900 rpm

Manufacturer

 N/A Eaton-Airflex

Actuation

 N/A Spring Applied, Air Release

General Description

N/A Model DBA brakes are spring applied, pressure released, disc style brakes. They develop equal torque in either direction of rotation. Their torque and thermal capacities allow them to be used in the most demanding applications.

Brake construction and operation is shown in the figure. Pressurizing the brake compresses the brake springs and withdraws the clamping plates from the brake discs. Standard brakes are furnished with either one or two discs, which are free to move axially.

Model DBA uses a rubber diaphragm to form the releasing pressure chamber and to serve as the releasing piston. Brake friction material is attached to stationary components. Brake discs are either solid or ventilated. The disc type is indicated by an S for solid, or V, for ventilated, in the brake model designation. Solid discs are used in applications requiring a heat sink and/or where engagement is infrequent. Ventilated discs are recommended for cyclic applications.

Torque ratings listed are for brakes with a standard compliment of springs. The quantity of springs can be varied to customize the torque of the brake to suit a particular application. Consult the factory for brake torque of units with nonstandard spring configurations.

Brake sizes are indicated by the number of brake discs and the disc diameter in inches. For instance, size 229DBA has two discs 29 inches in diameter.

  • 1 Tolerance +0.000/-0.003 in (+0,00/-0,08 mm)
  • 2 Dynamic torque shown. Static torque approximately 1.15 greater. Torque values are for new linings. Torque decreases with lining wear. At the worn out condition, torque is approximately 0.66 of values shown.