air brake safety valve factory

There is no application guide that tells us what air brake valves the manufacturer used on your truck or trailer. The onlypeople who can tell you what valve the vehicle manufacturer used based on a VIN are the vehicle dealers. With that said,there are other ways to determine which valve you need. You may find a label or a metal tag on the valve that has theOEM part number printed on it. Sometimes, the number is stamped right on the valve body. Raised casting numbers are usuallyno help at all. You"re looking for stamped numbers here.

If you can"t find any numbers, you can look for a match based on the pictures we provide here on AnythingTruck.com. This iseasiest if you know at least what type of valve you"re working with. Is it a relay valve or push-pull valve? If you have noidea what kind of brake valve you"re replacing, you will probably benefit from looking over the Bendix Air Brake Handbook.

We try to provide a comprehensive cross reference lists for each air brake valve we offer here, but there are always OE numberswe haven"t learned about yet. The list of pages below contains useful part number references from OE valve manufacturers. Youcan try your part number at the sites listed or just give us a call or drop us an email for help.Bendix Part Number SearchUse this if you have a Bendix part number and want to find their current number.

Determine the port(s) improperly emitting air pressure and perform the following service checks:Exhaust port leakage at rest - Disconnect the delivery lines. If the leak stops,inspect the device at the other end of the delivery line for leakage. If the leakagecontinues, inspect and repair or replace the leaking valve.

Always blow out all attaching lines and reservoirs when installing a replacement valve to purge any contamination from the system. Avoid using thread sealant or tape as excess material can itself contaminate the air device.

The most common cause of governor failure is contamination. Blow out all attachinglines, hoses, etc when replacing a governor. Make sure the reservoir pressure sensingline is routed from the reservoir so that no contamination may enter the line and passinto the governor. A replacement D-2 air governor can be found here.

Compressors that are passing excessive oil as evidenced by the presence ofoil at valve exhaust ports or seeping from air inlets is usually a result of:Restricted air intake - Check the compressor air filter and replace as necessary.Check the compressor air intake hose for kinks, excessive bends, and a minimum ID of 5/8".

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Valves direct the flow and release of air throughout an air brake system … a big job for the network of compact components located on an 80,000 pound vehicle. But when it comes to product performance and support, Bendix valves have set the standard for everyone else.

If you want to maintain performance, reliability, and even safety, go with the best, stay with the best… genuine Bendix. Why take a chance with anything less?

Genuine Bendix valves – whether new or remanufactured – reflect today’s highest engineering standards and comply with all federal safety regulations. In fact, genuine Bendix is the industry standard valve system chosen by leading OE manufacturers throughout North America.

Commercial vehicles are becoming more sophisticated and compressed air requirements are increasing daily. That’s why we’re always hard at work developing and testing the next generation of valves and control system components designed to enhance and improve vehicle performance. With highly sophisticated R&D activities and up-to-date expertise from around the globe, we continue to ensure each new design meets and exceeds your needs.

As well, the compressor in the system is capable of pumping air pressure to 500 psi (3450kPa), which poses danger to both the driver and others around the vehicle.

The driver of a commercial vehicle must know that the safety valve makes the sound of a machine gun when it releases excess air pressure from the system.

Velvac® PTO Combo Valve with Shift Tower controls PTO and dump pump operations. Features 1/4 inch brass push-to-connect fittings included on valve assembly. Shift tower measures 4 5/8 inch x 3 5/8 inch x 8 inch H overall with 2 inch access hole and mounting holes 4 1/4 on center.

Velvac® Height Control Valves comes with fitting package and has 1/4” NPT. Replaces: Barksdale KD2357, Volvo 85112638, Volvo 85108667, Volvo 85112623, Mack 99QK148M.

Velvac® Integral Dump Leveling Valve fits Kenworth Chassis w/ dump and Volvo Chassis, has 1/4" NPT ports and replacesHaldex PR 90554950, 90554945, Barksdale KD2374.

Velvac® Integral Dump Leveling Valve fits International and Peterbuilt Chassis w/ Dump, has 1/4" NPT ports and replacesInternational 2506169C91, Hadley HAD500NS, Barksdale KD2360.

Velvac® Cab Leveling Height Control Valves fit Peterbuilt and International cabs, have 1/4" NPT ports and replaces WABCO S464 007 004-0 and Barksdale KD2355 valves.

Velvac® SR-5 style spring brake valve controls the application and release of spring brakes during normal and emergency situations. Replaces Bendix 065437

Velvac® Universal Solenoid Kit replaces existing solenoids found on Kysor, Bendix and Horton fan clutches. Kit includes valve, wire harness with Weather-Pack sealed connectors, exhaust shield, in-line fitter and butt connectors.

Velvac® Air Solenoid Valve is a direct replacement for Neway 90054075 which is normally open. Features include: 12 VDC, 10 watts, 100 psi maximum operating pressure and 1/4 inch threads. (Intermittent use only)

Velvac® Standard Leveling Height Control Valves fit Volvo Chassis, have 1/4" NPT ports and replacesDelco King of the Road12C-1 (KOR 5549705) & 12-6-2 (KOR 5549706), Barksdale KD2373.

Velvac® Rapid Air Dump Suspension Valve is a pilot operated valve. It has (4) 1/8” FPT ports and a dual delivery design that allows for in-line plumbing of air spring lines

Phillips® 1/2" x 3/8" x 3/8" quick release valve has a corrosion resistant aluminum die-cast that is used to speed up the exhaust of air from the air chambers.

Phillips® 3/8" x 3/8" x 3/8" quick release valve has a corrosion resistant aluminum die-cast that is used to speed up the exhaust of air from the air chambers.

Velvac® RV-1 style pressure reducing valve is used in various applications where a constant set air pressure lower than the supply pressure is required.

Velvac® R-8 style relay valve incorporates an integral double check valve with a balance port connection which provides both an anti-compounding or quick exhaust feature. Replaces Bendix 286370 & 286371

Velvac® Air Tractor Control Kit adds foot control to trucks with pre-FMVSS 121 air brakes hauling an air brake trailer. Kit includes: Hose assembly jumper lines, support springs and fittings.

Velvac® ST-4 Pressure Release Safety Valve is primarily used on vehicles with air suspension or air brake systems. Automatic pressure release at 175 Psi.

Velvac® Height and Lumbar Control Seat Valve is primarily used on vehicles with air suspension seat systems. Has (2) 1/8 in FPT ports, 1 on the side and 1 on the end.

Velvac® Height and Lumbar Control Seat Valve is primarily used on vehicles with air suspension seat systems. Has (2) 1/8 in FPT ports, both on the end.

VELVAC Height and Lumbar Control Seat Valve is primarily used on vehicles with air suspension seat systems. Has (1) 1/8 in. FPT port on the end and (2) 1/4 in. blade terminals.

Velvac® Three-way valve with remote 1/4" NPT exhaust air pilot reset option for use with single acting air cylinders, lift axles or suspension systems.

VELVAC four position valve operates systems where full air or vacuum pressure must be isolated and has a newly designed orifice area that increases airflow 30 - 40% in comparison to previous valves.

VELVAC Three-Way On/Off Exhaust Solenoid has a 100-200 psi standard operating pressure and must be mounted vertically with the air inlet port facing upward.

Velvac® Air Three-Way Flapper Valve for Freightliner features push-connect fittings that mate easily with 1/4 inch nylon tubing for easy installation and 150 psi maximum operating pressure.

Velvac® Air-Electric Three-Way Toggle Valve for Peterbuilt features push-connect fittings that mate easily with 1/4 inch nylon tubing for easy installation and 150 psi maximum operating pressure.

Velvac® Air-Electric Three-Way Toggle Valve for Mack features push-connect fittings that mate easily with 1/4 inch nylon tubing for easy installation and 150 psi maximum operating pressure.

Velvac® Air-Electric Three-Way Toggle Valve for Kenworth and Volvo feature push-connect fittings that mate easily with 1/4 inch nylon tubing for easy installation and 150 psi maximum operating pressure.

Velvac® Air Three-Way Toggle Valve for Kenworth and Volvo feature push-connect fittings that mate easily with 1/4 inch nylon tubing for easy installation and 150 psi maximum operating pressure.

Velvac® Air Three-Way Toggle Valve for Mack features push-connect fittings that mate easily with 1/4 inch nylon tubing for easy installation and 150 psi maximum operating pressure.

Velvac® Height and Lumbar Control Seat Valve is primarily used on vehicles with air suspension seat systems. Has (2) 3/16 in barb ports on the end. Paddle Type.

Velvac® Universal Three-Way Toggle Valve has 1/8 inch NPT supply and delivery (2) ports and includes a chrome-plated flip handle. (Faceplate sold separately)

Velvac® PTO Four-Way Control Valve Assembly is panel mounted and replaces Chelsea 328865X. Features include 1/8 inch - 27 NPTF, 150 psi maximum operating pressure and an operating temperature range from -20° to +200°F.

The Newstar air brake safety valve is designed to prevent the air brake reservoir from bursting from overpressure. Its design and engineering matches original equipment specifications.

Keep your air brake system working as efficiently as it should be by replacing any damaged valve with the Velvac air brake safety valve. This valve is made tough and durable and is rigorously tested to ensure it operates effectively in its respective application.

It’s impossible to fix something without understanding how it’s supposed to work. Brake system repair decisions can be difficult to make, and costly to execute, without a basic understanding of system components and their operation.

The following discussion details the operation of a typical S-cam air brake system on a single-axle tractor and trailer (see diagrams). Systems vary somewhat, depending on the manufacturer and on optional equipment and configuration, but all can be thought of as comprising three sub-systems.

The supply system, as the name implies, supplies pressurized air – the energy source for any air brake system. The key player in this sub-system is an engine-driven air compressor (1). A governor (2), which may be integrated with the compressor, controls the compressor’s output by unloading or cycling it. Pressure is generally maintained at 100 to 120 psi, and is monitored by the driver by means of dash-mounted pressure gauges (3). A low-pressure switch (4) senses system pressure and sends an electrical signal to a dash light or buzzer to alert the driver when air pressure falls below 60 psi.

Reservoirs, three per tractor and, usually, two per trailer, store the compressed air until it is needed to actuate the brakes. Check valves (5) prevent pressurized air in the primary and secondary reservoirs from passing back through the compressor while it is not running. A safety or “pop-off” valve (6) is usually installed in the reservoir closest to the compressor. In the event of over-pressurization, the safety valve allows air to escape, preventing damage to air lines, reservoirs and other components.

Effect of brake chamber type (diaphragm area) on pushrod output force, with constant 60-psi application. Except where noted, illustrations courtesy of ArvinMeritor, Bendix and Dana.

The reservoir closest to the compressor is often referred to as a wet tank, because that is where atmospheric moisture – the No. 1 enemy of air brake systems – condenses in the greatest quantities. Reservoirs are equipped with drain valves (7) so water can periodically be eliminated. These can be manually or automatically operated. Alcohol is sometimes introduced into air systems operating in cold climates to prevent water from freezing and plugging air lines.

An air dryer (8) is a device that condenses and eliminates most of the water from an air system. An air dryer is a canister that usually contains a bed of desiccant material. As air passes through, the material captures moisture and blow-by from the compressor.

The control system consists of a series of pneumatic valves that direct air and control pressure to appropriate components. Although discussed here individually, different valves are often combined in a common housing.

The main valve is the dual-control foot valve (9), so called because it is actually two valves that operate simultaneously, in response to input from the driver’s foot at the brake pedal.

Two valves are necessary because, after the wet tank output, the system splits into two separate brake circuits. Air downstream of the wet tank is divided between primary and secondary reservoirs. The split system ensures that, in the event of a failure, the entire system will not become inoperative, and the truck can be brought to a controlled stop.

When the brake pedal is depressed, air flows from the primary reservoir and through the primary portion of the dual-control foot valve to actuate the rear axle brakes. Meanwhile, air flows from the secondary reservoir, through the secondary portion of the dual-control foot valve, to actuate the front axle brakes. A two-way check valve (10) senses primary and secondary supply pressure, and allows the dominant pressure to actuate the trailer brakes. Primary air can also be manually supplied to the trailer by means of a hand valve, (11) usually located on or near the steering column.

Relay valves (13) are used on trailers and on the rear axles of long-wheel-based tractors to minimize delays of brake application due to length of plumbing. These valves are directly supplied with unmodulated air pressure, and use air from the dual-control foot valve or manual trailer valve as a signal to quickly direct air to the brakes they serve.

Relay valves come in a variety of “crack” pressures. Crack pressure is the air pressure value required at the input from the foot valve before the relay valve will send air pressure to the brakes controlled by that valve. Crack pressure is an important element of brake timing and balance, and is determined – axle by axle – by how heavily loaded the axle served by a valve is, how big its brakes are, and how aggressive the linings are on those brakes.

A valve that cracks at too low a pressure for a given axle can cause premature application, wheel lockup and trailer pushing, if the affected axle is on the tractor. Too high a crack pressure can cause delayed application, insufficient braking and trailer pushing, if the affected axle is on the trailer.

After a stop, when the driver lifts his foot from the brake pedal, a quick release valve (14) allows brake actuation air to be quickly exhausted near the brakes it serves, rather than having to travel back through the supply line, thus speeding brake release time.

Foundation brake operation. When pushrod is extended, brake adjuster, camshaft and S-cam rotate. S-cam spreads brake shoes apart and against brake drum.

Dash-mounted valves (15 and 16) control air pressure to the parking brakes. In most cases, these are spring brakes, so called because when no pressure is supplied, the brakes are applied by means of a spring. Air pressure, when applied, overcomes spring force and releases the brakes. More on that a little later.

A tractor protection valve (17) senses pressure in one or both lines that carry air to the trailer. These lines are connected to the trailer by means of quick-connect air fittings called gladhands. When there is no pressure in the line(s) – due to trailer breakaway or a gross air leak in the trailer circuit – the valve closes to maintain air pressure in the tractor circuit. In everyday use, the valve also works in conjunction with the dash-mounted trailer parking brake valve (16), to shut off air to the trailer circuit before disconnecting tractor from trailer.

The spring brake (or multi-function) valve (18) limits the air pressure used to keep the trailer parking brakes off and, by means of an integral check valve, isolates a failed reservoir, which would otherwise cause the parking brakes to be automatically applied.

Foundation brakes are where properly supplied and controlled air is used to stop a vehicle. When the brake pedal is depressed, air pressure is directed to brake chambers (19) at each wheel end. Brake chambers consist of a pressure housing, diaphragm and pushrod. As air pressure is exerted on the diaphragm, the pushrod on the other side of the diaphragm is extended. The force the pushrod exerts is the product of the amount of air pressure applied in psi, and the area of the diaphragm in square inches. For example, 60 psi, applied to a chamber with a 16-square-inch diaphragm would create a force at the pushrod of 960 pounds. A 60-psi application to a chamber with a 30-square-inch diaphragm would yield 1,800 pounds of pushrod force. Improperly matched brake chambers, therefore, can cause severe brake balance problems.

The pushrod is connected to one end of a lever called a brake adjuster – often called a slack adjuster (20). The other end of the brake adjuster is connected to a shaft that runs perpendicular to the plane formed by the pushrod and slack adjuster. As the pushrod is extended, the shaft rotates.

The shaft, in turn, is connected to an S-shaped cam between the brake shoes. As the shaft rotates, so does the cam. The brake shoes are forced apart and against the brake drum, creating the friction needed to slow the vehicle. The amount of friction produced is determined, in part, by the size of the brakes, the coefficient of friction (aggressiveness) of the brake lining material, and the mass and heat-rejection potential of the drum.

The slack adjuster is equipped with an adjusting mechanism to compensate for brake lining wear. If this were not so, the pushrod would be required to extend farther and farther as brake lining wear progressed. It wouldn’t take long before the pushrod would not be able to extend far enough to apply the brakes. Modern brake adjusters accomplish this automatically.

The brake adjuster has another function. It is essentially a lever, and a lever multiplies force in proportion to its length. A 4-inch long brake adjuster converts 1,000 pounds of force at the pushrod to 4,000 ib-in torque at the camshaft.

The brake adjuster’s length and the brake chamber’s size are two variables commonly altered to meet braking requirements. The product of these two values is expressed as the “AL factor.” This factor, when multiplied by 60 psi air pressure, is the industry standard for braking calculations.

For example, 60 psi, applied to a chamber with a 16-square-inch diaphragm (the “A” part of the AL factor) would create a 960-pound pushrod force. Multiplied by a 4-inch brake adjuster (L), the actual torque on the brake camshaft would be 3,840 lb-in.

In addition to applying the service brakes used in everyday driving, the brake chambers on the rear tractor axles and on the trailer axles apply the parking brakes. These brake chambers, (spring brakes), incorporate a second chamber, containing a second diaphragm and a powerful spring.

When the vehicle is in use, the dash-mounted parking brake valves are in the “run” (pushed-in) position. This supplies air pressure to the spring chamber, on the side of the diaphragm opposite the spring. Air pressure acting on the diaphragm compresses the spring, and the parking brakes are held off. This does not affect the operation of the service brakes.

When the vehicle is parked, the dash valves are pulled out. This exhausts spring brake hold-off air, allowing the spring to apply the parking brakes. In the event of a loss of system pressure, hold-off air pressure is overcome by the parking brake spring, and the brakes are automatically applied to provide emergency stopping.

Per federal regulations, the parking brakes must be able to hold a vehicle, loaded to its gross weight rating, stationary on a smooth, dry, concrete roadway, facing uphill or downhill, on a 20 percent grade.

We hope that this overview of air brake basics helped clarify your understanding and provide a grounding for dealing with more complex braking topics to be covered in future issues of CCJ.

Zhejiang VOB Technology Co., Ltd is one of the powerful Hand Brake Valve Manufacturers and Hand Brake Valve Factory, our company was built on the basis of Dongshan Auto Parts Factory in 1990 and owns Zhuji Dongshen Auto Parts Factory, Shanghai Fuao Auto Parts Co., Ltd., Dongshen fuel supply station, and Dongshen motor Transportation Team. Operating brands:SHANGHAl FUAO,FAQP world-renowned market, the series of bus faqp Brake Chambers in Asia and Europe, the Middle East, the Americas market, with foreign countries and many well-knownbridge factory for many years. our factory covers an area of 40 acres, covers an area of 26666 square meters, points including stamping, diecasting, CNC finishing, assembly workshop. Company comprehensive practice of modern enterprisemanagement system, through the ISO/TS 16949 quality management certification, the height of productioninformation, our company in good faith for the purpose of win-win, innovationbeyond, to become the leader of the industry!

A hand brake, also known as an emergency brake or e-brake, is a mechanism used to slow or stop a vehicle in an emergency situation. The hand brake valve is the part of the hand brake system that controls the flow of brake fluid to the brakes. It is typically located in the center console of the vehicle, near the driver"s seat, and is activated by pulling on a lever or pressing a button. When the hand brake valve is activated, it sends a signal to the brake system to apply the brakes. The hand brake is typically used in addition to the regular foot brake and is intended as a backup in case of failure or emergency.

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Under California Civil Code Section 1789.3, California users of the Services are entitled to the following specific consumer rights notice:  The Complaint Assistance Unit of the Division of Consumer Services of the California Department of Consumer Affairs may be contacted in writing at 1625 North Market Blvd., Suite N 112, Sacramento CA 95834, or by telephone at (916) 445-1254 or (800) 952-5210.

Manufacturer of valves for aerospace, nuclear, scientific & industrial applications. Valves for aerospace applications include solenoid latching valves, relief valves, lubrication oil selector valves, air speed sensing selector valves, shut off valves, hot gas valves, solenoid valves, pressure relief valves & float inflation valves. Valves for nuclear applications include check valves such as flow check valves, multi-way valves, in-line check valves & gate valves. Two-way valves include direct, pilot assist, balanced disc, gates & direct lift valves. Three-way valves include general & multi-purpose solenoid valves, instrumentation class solenoid valves, diaphragm isolated solenoid valves & PTFE isolated solenoid valves. Scientific & industrial valves include multi-purpose solenoid valves, cryogenic solenoid valves, instrumentation class solenoid valves, diaphragm isolated solenoid valves, PTFE isolated solenoid valves & pinch valves. Fluid metering & dispensing pumps are also available. Valves meet Military Specs & IEEE standards.

Bendix Commercial Vehicle Systems develops and supplies leading-edge active safety technologies, energy management solutions, and air brake charging, control systems, and components. The Bendix® brand name is seen on and trusted throughout North America for medium- and heavy-duty trucks, tractors, trailers, buses, and other commercial vehicles.

Bendix is a leading worldwide supplier of active vehicle safety systems in the commercial vehicle industry. Bendix provides a full range of wheel-end components and systems, plus integrated vehicle modules, and more, not only just in North America, but also in Europe and Australia.

A member of the Knorr-Bremse Group, Bendix delivers solutions for improved vehicle performance, safety, and overall operating cost. Employing more than 3,200 workers, Bendix Commercial Vehicle Systems is headquartered in Elyria, Ohio, and has manufacturing plants in Acuña, Mexico, Bowling Green, Kentucky, and Huntington, Indiana.

The type of spring-loaded valve shown (Fig. 32) requires that the driver push the button to release the parking brakes. If the air pressure in the system falls below approximately 70 psi (483 kPa), the spring brakes may begin to drag and if it falls between 20-45 psi (138-310 kPa), will fully apply. On many vehicles the parking brake control valve on the dash will close, however some valves may never close. The important thing is that the spring brakes are fully applied before the air is depleted. Always ensure the spring brakes have been fully applied. Similar types of spring-loaded valves require you to pull the button out to release the parking brakes.

Note: On some newer models the park brake button will not pop out automatically. However, the brakes will still apply. There is a toggle control valve in use that does not have an automatic brake application feature. The park brakes will gradually apply as the air pressure is depleted, however, the control valve will not move. When air pressure is restored, the park brakes will release if the toggle valve is not manually moved to the park brake “on” position.

CAUTION: Compounding the brakes happens when a service brake application is made with the park brake still applied. This can result in damaged brake components and possibly brake failure. To avoid compounding, the park brake should be released before a foot brake application is made.

Note:An anti-compound line (see Fig. 34) is sometimes installed between the delivery side of the primary circuit relay valve and the control side of the relay valve operating the spring brakes. When a brake application is made, the relay valve operating the spring brakes gets a signal from the service brake to release the spring brakes with the same amount of pressure applied to the service brakes. This prevents service-brake and spring-brake pressure from compounding on the brake linkages.

With air pressure of 70 psi (483 kPa) or greater acting upon the emergency diaphragm (A) and piston (B) in the spring hold-off cavity, the spring (C) is fully compressed and the piston (B) is held in the released position. This does not affect the service diaphragm (D) or service push plate and rod (E).

When you operate the park control valve, air is exhausted from the spring hold-off cavity. The spring (C) is now allowed to extend, forcing the piston (B) and the diaphragm (A) forward. The piston (B) forces the service diaphragm (D) and service push plate and rod (E) forward compressing the return spring (F) and applying the brakes. To release the park application, the park control valve is placed in the release position, releasing the brakes as described under “System charged - normal running condition.”

During a controlled service brake application, air pressure enters the service port and acts upon the service diaphragm (D), which forces the service push plate and rod (E) forward, applying force to the slack adjuster. The slack adjuster rotates the camshaft and applies the brakes. The emergency spring is held in the compressed position by air pressure in the spring hold-off cavity.