The Air Brake Handbook ©2004 Bendix Commercial Vehicle Systems LLC • All Rights Reserved
The Air Brake Handbook ©2004 Bendix Commercial Vehicle Systems LLC • All Rights Reserved www.bendix.
Device Index Device Index F A ™ A-18 Controller Assy. . . . . . . . . . . Actuators . . . . . . . . . . . . . . . . . . . . . AD-2™ Air Dryer . . . . . . . . . . . . . . . AD-4™ Air Dryer . . . . . . . . . . . . . . . AD-9™ Air Dryer . . . . . . . . . . . . . . . AD-IP™ Air Dryer . . . . . . . . . . . . . . AD-IS™ Air Dryer Module . . . . . . . . AD-SP™ Air Dryer . . . . . . . . . . . . . . AF-3™ In-line Air Filter . . . . . . . . . . Air Disc Brakes . . . . . . . . . . . . . . . .
Handbook Section Index How to use the Air Brake Handbook This nine-section handbook provides an introduction to the use and operation of Bendix air brake systems and devices. Components are introduced and shown with typical system diagrams to show where they are used. As new components are introduced and their function explained, they gradually build up to a complete functioning air brake system. Partial system-drawings, throughout the manual, assist in explaining of the use of the components.
General Precautions IMPORTANT The systems presented in this manual are intended for illustrative purposes only and are not intended to be used for actual vehicle piping. Air Brake System General Precautions WARNING! PLEASE READ AND FOLLOW THESE INSTRUCTIONS TO AVOID PERSONAL INJURY OR DEATH: When working on or around a vehicle, the following general precautions should be observed at all times. 1. Park the vehicle on a level surface, apply the parking brakes, and always block the wheels.
Introduction Section 1: One-Page Introduction Air Supply The vehicle’s compressor takes in filtered air, either at atmospheric pressure from the outside (or already at an increased pressure, from the engine turbocharger in some cases), and compresses it. The compressed air is delivered to the air dryer where water and a small amount of oil is removed.
Overview Section 2: The Charging System The charging system consists of: • An air compressor • A governor, to control when the compressor needs to build, or stop building, air for the system and also to control the air dryer purge cycle • An air dryer, to remove water and oil droplets from the air • Reservoirs (or “air tanks”) to store air to be used for vehicle braking, etc.
Compressors drops to the “cut-in” setting of the governor, the governor returns the compressor back to building air and the air dryer to air drying mode. As the atmospheric air is compressed, all the water vapor originally in the air is carried along into the air system, as well as a small amount of the compressor lubricating oil as vapor. The duty cycle is the ratio of time the compressor spends building air to the total engine running time.
Compressors Single-Cylinder Compressors Two-Cylinder Compressors BX-2150™ air compressor Tu-Flo® 700 air compressor Tu-Flo® 501 air compressor Tu-Flo® 500 air compressor Tu-Flo® 400 air compressor BA-921™ air compressor nd lu En ers br g i Tu icat ne/ rb ed se lf o in ava le i t l.? co Wa opt ol te ion ed r/ ? av airail .
Compressor Maintenance Guidelines Maintenance Schedule and Usage Guidelines Regularly scheduled maintenance is the single most important factor in maintaining the air brake charging system. The table below is an introduction to the maintenance intervals for air brake charging systems. See your compressor and/or air dryer Service Data sheet for more information. If you are concerned that a compressor may be passing oil, use the BASIC™ Test Kit: Order Bendix P/N 5013711. Low Air Use Low Air Use e.g.
Governors and Components Governors and Components The Governor monitors the air pressure in the supply reservoir and operates the compressor unloading mechanism to control whether the compressor builds air pressure or not. The Bendix® D-2™ governor is an adjustable pistontype valve available preset to a choice of pressure settings.
Reservoirs and Components Reservoirs (or “air tanks”) serve the air brake system as a storage tank for compressed air. The reservoir size is selected by the vehicle manufacturer to provide an adequate amount of air for use by the braking system and other control devices. Bendix reservoirs are built in accordance with SAE specifications and are available in various sizes in both single and double compartment design configurations, and are certified to comply with government regulations (such as FMVSS 121).
Air Dryers Air Dryers The air dryer is an in-line filtration system that removes both water vapor and oil droplets from the compressor discharge air after it leaves the compressor. This results in cleaner, drier air being supplied to the air brake system, and aids in the prevention of air line and component freeze-ups in winter weather. Air dryers typically use a replaceable cartridge containing a desiccant material and an oil separator.
Air Dryers and Filters AD-SP™ Air Dryer SC-PR™ Valve (installation uses SC-PR™ valve) The AD-SP™ air dryer uses a small amount of air from the supply and front axle (secondary) reservoirs to perform the purge function. Because of this difference, the AD-SP™ air dryer is smaller and lighter than air dryers that have their purge volume within the dryer canister. An SC-PR ™ Single Check Protection Valve is used in conjunction with the AD-SP™ air dryer.
Miscellaneous Charging System Related Components A double check valve is used in the air system when a single function or component must receive air from, or be controlled by, the higher of two sources of pressure. An internal disc or shuttle moves in response to the higher air pressure and allows that air source to flow out of the delivery port. It is recommended that double check valves be mounted so that the shuttle (or disc) operates horizontally.
Bendix Videos and Literature Available Audio Visual Programs Number Description Package Cost $ Format to Order Quantity Per Item Air Brake Systems BW1673 Four-part Video System Training with Workbooks . . 1 set . . . . . . . . . 30.00 . . . . . . . . VHS/Book BW1678 Workbook for BW1673 . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 . . . . . . . . . . 2.00 . . . . . . . . . . . . . Book BW1957 Four-part Video only . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 . . . . . . . . . 15.
Bendix Videos and Literature Available (continued) Number to Order Binders BW1532 Description Package Quantity Cost $ Per Item Format Empty Binder for Catalog, Service Manual & Bulletins . . . 1 . . . . . . . . . . 5.00 . . . . . . . . . . . Catalog Troubleshooting Cards & Wall Charts Systems-Air BW902 Bus System Wall Chart . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 BW1555 Air Pressure Balance Test . . . . . . . . . . . . . . . . . . . . . . . . . 10 BW1231 Dual Systems Wallchart . . .
Service Data Sheet Index Service Data Sheets Download from www.bendix.com, order (like parts) by BW number, or order the complete Service Data Catalog (BW9600) Device . . . . . . . . . . . . . . . . . . . . . . . . . . SD number . . . (BW #) Device . . . . . . . . . . . . . . . . . . . . . . . . . . SD number . . . (BW #) A-18™ Trailer ABS EC-14 ™ Antilock Controller Assy . . . . . . . . SD-13-4784 . . (BW1670) ™ ™ (Gen 4 and Gen 5 ABS) . . . . . . . . . . . . . . SD-13-4757 . .
Service Data Sheet Index, continued For the complete Service Data Sheet Catalog, order BW9600 Device . . . . . . . . . . . . . . . . . . . . . . . . . . SD number . . . (BW #) Device . . . . . . . . . . . . . . . . . . . . . . . . . . SD number . . . (BW #) QR-L™ Quick Release Valve – Inline . . . . . . . SD-03-906 . . (BW1808) TC-2™ Trailer Control Brake Valve . . . . . . . . SD-03-813 . . (BW1430) QRN-2™ Quick Release Valve . . . . . . . . . . . . SD-03-907 . .
About Bendix Commercial Vehicle Systems LLC We supply air brake charging and control systems and components, vehicle modules, and leading-edge safety technologies under the Bendix® brand name for medium- and heavy-duty trucks, tractors, trailers, buses and other commercial vehicles in North America, Europe and Australia. Employing more than 1,800 people, Bendix is headquartered in Elyria, Ohio, with manufacturing plants in the U.S. and Mexico.
