Jonathan Doubinsky, Product Line Leader for Brake Chambers and Automatic Slack Adjuster at Wabco, talks to CVW about brake actuation technology.
Q. Where do these products fit in the overall braking system?
Jonathan Doubinsky (JD): Wabco‘s brake chambers – available for air disc, wedge, and cam brake applications – are a fundamental part of the wheel end. They transform the energy of compressed air into mechanical movements with high forces to reliably actuate the brake, thus bringing the vehicle to a safe stop.
Spring brake chambers are also able to keep the brake in a parked position by providing clamping force in line with respective regulations.
The Wabco EasyFit Automatic Slack Adjuster, on the other hand, is a vital part of the S-Cam drum brake. It acts as a lever and helps to constantly ensure the adjustment of running clearance between brake lining and drum, even under extreme temperature conditions.
Q. What are the differences between your Unistop, Tristop, and Tristop D products?
JD: Today’s customers can choose from a full range of brake chamber variants for different vehicle applications consisting of service brake chambers, double diaphragm spring brake chambers, and piston type spring brake chambers. Whilst Wabco’s Unistop reliably actuates the service brake, Tristop and Tristop D are spring brake types, which also enable parking and emergency braking.
Wabco’s spring brake chambers feature a fully-sealed parking chamber with internal breathing valve (IBV), coil clash-free design, and redundant sealing, which provide superior brake chamber life and vehicle uptime. Whilst Tristop is a piston-type spring brake chamber with a service pressure up to 13 bar/188 psi, Wabco’s double diaphragm spring brake chamber Tristop D reaches a service pressure up to 10 bar/145 psi, so is perfectly adapted to trailer needs providing an optimised TCO-solution.
Furthermore, our customers can choose from a broad range of different performance levels of Tristop D, reaching from basic solutions with open-hole design up to premium variants with a new integrated release bolt (IRB) design.
This new IRB design eliminates an external release bolt and dust plug, thus significantly improving serviceability and helping to maximize protection against exterior contamination.
Q. What makes the Wabco EasyFit Automatic Slack Adjuster an ‘easy fit’?
JD: Wabco’s automatic slack adjuster is designed to be maintenance-free. Easy, accurate, and quick installation of the device and its self-setting function avoid additional adjustment work once the product is installed in the vehicle.
Q. How does the Wabco EasyFit Automatic Slack Adjuster benefit fleets?
JD: The clearance sensing principle helps to maintain optimal brake clearance between brake lining and drum, even under extreme temperature conditions. This decreases the risk of hot runners due to our unique adjustment behavior.
The powder coating and robust rubber sealing enable a long product life. Furthermore, Wabco’s automatic slack adjuster features full lifetime lubrication and, hence, does not require any quarterly greasing, which significantly reduces service times and TCO.
Q. What are the differences between your products and similar products on the market?
JD: Whilst traditional automatic slack adjusters require a quarterly greasing, the Wabco EasyFit automatic slack adjuster is designed with full lifetime lubrication to keep fleets on the road.
The clearance sensing principle helps to maintain optimal brake clearance between brake lining and drum, reducing the risk of hot runners and supporting to optimise the wear behaviour of these components.
In addition, powder coating and Wabco-designed rubber sealing provide outstanding robustness over the product lifetime.