Advanced bogie brake systems

Conference On Railway Engineering Wellington, Sept 12-15, 2010

Advanced Bogie Brakes David Wynd

B.Eng (Mech)(Hons), M.Eng(ID)(Dist) Matthew Connelly B.Eng(Mech)(Hons)

Faiveley Transport Australia Limited

SUMMARY As freight rolling stock operators focus on the need for greater improvements in efficiency and safety, there is a significant need for advances in wagon brake systems. Emerging system applications such as the ECP brake system are allowing freight rolling stock operators and maintainers to benefit from higher network capacity and reduced maintenance costs due to improved brake wear. Advanced bogie brake systems, that include integrated brake cylinders, slack adjustors and spring park brakes are adding to these benefits through additional capacity improvements, significant safety improvements for operators and maintainers and optimized life cycle costs. In this paper, Faiveley Transport will place particular emphasis on how the application of advanced bogie brake systems can significantly improve: Safety for rollingstock operators and maintainers Operational efficiency Reduced installation, maintenance and life cycle costs Advanced bogie brake systems that incorporate automated parking brake equipment add to the operational efficiency of the freight network, whilst simultaneously delivering considerable improvements in safety for operation and maintenance personnel and reducing the weight of the wagon. Furthermore, such advanced systems can be retro-fitted in to existing wagons as well as incorporated in to new wagons during the manufacturing stage.

INTRODUCTION Safety is a key concern for all rail operators. However current freight operations generally still require the manual application of park brakes, necessitating the trackside exposure of individuals. When park brakes are applied, indication of the application is local to the bogie and difficult to distinguish; other controls, such as flagging of applied hand brakes are administrative and open to human error. In a worst case scenario brakes may be dragged due to park brakes not being released1, or wagons runaway due to park brakes not being sufficiently applied2. The aim of this paper is to introduce an alternative for bogie brakes now available to the Australian and New Zealand market which feature an integrated spring park brake. This family of brake equipment suitable for both freight wagons and

1 Rail Accident Investigation Branch, Freight train derailment at

Hatherley, near Cheltenham Spa, 18 October 2005, dated July 2006. 2 Rail Accident Investigation Branch, Runaway and collision at

Armathwaite, 28 January 2007, dated April 2008.

passenger cars, is based on the proven Faiveley BFC actuator product. NOTATION AAR Association of American Railways BFC Faiveley Transport tread brake unit BFCB Faiveley Transport brake beam unit incorporating BFC technology BFCBF Faiveley Transport brake beam unit incorporating a spring park brake ECP electronically controlled pneumatic brakes for freight applications, based on AAR specifications. UIC Union of International Railways THE BFCB FAMILY OF BOGIE BRAKES Faiveley Transports BFCB family of brake equipment is based on the successful BFC integrated tread brake unit used on many Locomotives, EMUs and DMUs, with 127,000 units delivered world wide since 1978. One of the most recent new applications is on the motor car of the Matangi fleet of trains.

David Wynd and Matthew Connelly Advanced Bogie Brakes Faiveley Transport Australia Limited


The BFCB literally meaning BFC with Beam, has been in service since 1999 with applications in the UK, Finland, Sweden, South Africa, Germany, Australia and New Zealand. Functionally the BFCB replaces the brake cylinder, slack adjuster and rigging system on the wagon similarly to other products on the market, however variants of the BFCB are installed on both single axle wagons or in bogies, and in both retrofit of old vehicles and new build vehicles. The BFCB family currently consist of three variants:

Push Brake Clasp Brake Push Low Brake

The BFCB Push Brake, shown in Figure 1, is intended for bogie installation. The brake consists of two opposing BFC brake units connected by push rods, applying compressive effort to the wheel treads via the brake beams. This application is used on both UIC and AAR bogies, having a total weight of approximately 200kg and an available block force between 10-50 kN. The BFCB Clasp Brake, shown in Figure 2, is intended for single axle installations, with the most recent example being introduced on KiwiRails

overhauled AK cars. The brake consists of a single BFC, with the beams connected via a clasp passing over the wheel pair axle. The clasp brake has an approximate mass of 190kg, and an available block force of up to 25kN.

Figure 2: BFCB Clasp Brake

The BFCB Push Low, shown in Figure 3 is an application designed for bogies without the possibility for the push rods passing through the bogie. Rather the beams are connected via a second beam passing below the bogie. As this application only allows for a single BFC, the available block force is limited, like the Clasp Brake, to 25kN. While this application exposes the

Figure 1: BFCB Push Brake



bottom of the brake to on track debris such as spilt ores, the form for the beam means the unit easily ploughs through with little problems reported with this application.

Figure 3: BFCB Push Low Brake FULLY INTEGRATED SPRING PARK BRAKE THE BFCBF Like competing products, the BFCB may also be applied via a mechanical linkage, however unlike all other applications the BFCB may also be installed with a fully integrated spring park brake. The spring park brake for BFCB is a modular component which is added to the BFC. BFCB with a spring park brake added is known as a BFCBF. As the spring park brake of the BFCBF is applied when the pressure to it is released, it is both automatic and failsafe. As it is tied into the trains pneumatics, it is also applied uniformly across the entire rake of wagons, unlike the application of manual park brakes where a minimum number of wagons close to the Locomotive have their brakes applied. The spring park brake includes an in-built anti-compounding valve which prevents both service and park brake forces being applied simultaneously preventing damage to the wagon. While the BFCBF may be used with conventional pneumatic only systems, with the inclusion of ECP control, it will be possible to utilise the spring park brake feature of the BFCBF to deliver a push button application of parking brakes across an entire train. ADVANTAGES The BFCB family provides significant advantages over previous bogie brake systems in Safety, Weight, Operational Benefits, Reliability, Maintenance and Life Cycle Costs (LCC). 1. Safety

The BFCBF bogie brake system with integrated spring park brake is designed to eliminate the need for manual application and release of park brakes. In doing so it

eliminates the need for drivers and yard staff to walk along track to apply and release park brakes. The elimination of the hand wheel of mechanical park brake also eliminates the exposure to the chain, release handle and locking device. In maintenance, as the BFCB brake shoes are replaced from outside the bogie, there is no need for fitters to move between or underneath wagons.

2. Weight The integration of the BFCB family of bogie brakes provides reduced total brake system weight due to the elimination of brake hangers and park brake operating equipment such as the hand wheel, chains, release mechanism, blocks and other items. This reduction translates to an increased yield capacity per wagon.

3. Operational Benefits The Spring Park Brake of the BFCBF eliminates the need for a railway worker to be present when the wagons are parked in sidings or a yard to apply or remove the manual handwheel park brake. The spring park brake reduces the risk of dragging wheels due to human error where a manual hand park brake is not released. Experience of previous installations of BFCB equipment has shown that the way the system is tuned to each wagon and bogie design, gives very even brake block wear compared with other types of brake beam and rigging.

4. Reliability, Maintenance and LCC The BFCB brake beam equipment is designed to be preventative maintenance free between overhauls. The standard overhaul period for the equipment is 6 years, but experience of other similar installations of this equipment indicates that it may be possible to extend this period, further reducing the through life cost of maintaining the equipment. The low number of moving parts and joints in the BFCB equipment reduces the complexity of the brake system, leading to reduced failure modes. This also eliminates the need for preventative maintenance such as the application of grease and lubricants. In particular the elimination of hand wheels, chains and pulleys of manual park brakes eliminates all fault modes associated with these components, which are common and have been the cause of accidents3.

3 Office of Transport Safety Investigations, Rail Safety

Investigation Report, Runaway grain wagon, Temora, 28 July 2009, undated



Based on usage estimates, over the course of the 30 year life expectancy of the wagon, it is anticipated that no more than 80 hours of Overhaul time and 2 hours of Corrective Maintenance are required per wagon. This figure is from a preliminary calculation that is to be reviewed, and is likely to be reduced, with more detailed inputs. No special tools are required for corrective or preventative maintenance of the equipment.

ASSEMBLY AND OPERATION The BFC family of actuators have been successfully deployed in the past in a range of applications taking various mechanical forms. The proposed solution detailed here is a brake beam design with the force from two actuators distributed over four wheels. The modular design of the brake beam lends itself to customisation for specific projects and application in various gauges. Each assembly is unique to a project, as an illustrative example of the brake beam form, the BFCB DA 120 and BFCBF DA 120 used on the QR Rail Grinder project are shown in Figure 1 and Figure 4.

Figure 4: Brake Beam Section

The mechanical assembly includes vibration resistant bolted connections well proven in similar applications such as Heavy Haul AAR bogies, providing the customer with an assurance of joint quality while enabling full disassembly of the Brake Beam if required. Each part of the brake beam may be removed and replaced separately under deep maintenance or repair; such as damage to the brake block holder which would require

complete replacement of conventional units. This greatly increases the overall availability of the system with a minimum of spares required on hand, reducing the time to repair compared to a single piece welded unit.

The mechanical assembly is compatible with AAR compliant bogies, with the actuator push rods passing through the Bolster. Sufficient clearance is available between the bolster and actuator rods to enable full operational suspension travel in crush and tare.

Figure 5: Brake block change

The design of the mechanical assembly enables the changing of the brake blocks from the side of the bogie, with no further disassembly required. Taking full advantage of the integrated double acting slack adjuster, the brake blocks may be changed from the side of the bogie with the use of a long bar, with no further disassembly required as per the process shown in Figure 5. Each brake block holder type is optimised specifically for the project requirements; as a result the brake blocks experience even, optimised wear, as can be seen in Figure 6 a sample brake block has been removed following 8 months of use, over 64,000km, with no noticeable tapered wear.

Figure 6: Used Brake Block from BFCB application on coal train in South Africa



CONCLUSION Like competing products, Faiveley Transports BFCB integrates the brake cylinder, slack adjuster and rigging system on the wagon, to a single bogie mounted unit. Unlike competing products, the BFCB may also integrate a modular spring park brake. In doing so, the brake unit becomes both automatic and fail safe providing the user with a clear safety advantage. With several applications in Europe and the UK now exceeding eight years of service, the reliability is being found to be very high indicating a reduction in life cycle costs when compared to other units. It is anticipated that further information on this will be available in the near future.

Advanced bogie brake systems

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