At agricultural machinery conferences across the country, engineers have been meeting to talk about implement braking. The topic is old news in Europe, where for years tractors have been used in place of trucks for hauling, and implement brakes are required. But in the states there is no law that mandates the use of auxiliary brakes.
That’s what standard developers like Brian Herbst are trying to change. The concern is that, without implement brakes, the tractor and implement could jackknife on the road or plow through an intersection without being able to stop. Such incidents have occurred in recent years as tractors have increased in speed and are being asked to pull loads formerly reserved for over-the-road trucks.
“If you look at the past 15 years, tractor speeds have doubled,” says Herbst, senior brake systems engineer with John Deere and member of the American Society of Agricultural and Biological Engineers (ASABE) Ag Equipment Braking Committee. “And the size of tractors and implements has doubled if not tripled or quadrupled. Everything is just getting so big and powerful that it’s something we need to look at and be proactive about.”
Herbst and others on the braking committee are revising the North American standard on braking performance for agricultural field equipment (ASAE S365) to mandate implement brakes under certain conditions. Sections 8 and 10 will address when implement brakes are required, the types of implement brakes to be used, and the system requirements for both tractors and implements.
“Our goal is to develop an adequate standard for implement brakes and work with the industry to abide by it so that equipment makers can be self-regulated,” Herbst explains.
ASABE expects to finalize the sections this year and publish them next year. In the meantime, braking experts recommend farmers learn a few key facts about braking to help guide their tractor and implement purchases:
1 Above 20 mph, you need implement brakes.
Implement brakes currently are not mandatory in North America but have been highly recommended since the braking standard was first revised in March 1983. Herbst is working on a guide to let farmers know when their equipment should have implement brakes, which should be out later this year. “As a rule of thumb, if you are pulling heavy loads at speeds above 20 mph, the implement should be equipped with brakes,” he says.
2 Over-the-road hauling requires safety.
Wade Prouse, New Holland high-horsepower tractor product marketing manager, says farmers need to be aware of what loads they will need to haul, speeds at which they will be hauled, and types of brakes offered.
“Developments in brakes may be of concern to farmers in situations such as over-the-road hauling,” Prouse says. “Many tractors now offer 31-mph road speed, which leads to customers using the tractors for more hauling applications and therefore more need for safety on the roads.”
3 Trailer brakes come in three types.
The three types of trailer brakes for implements are hydraulic, pneumatic (air), and electric. In the U.S., hydraulic brakes are the most common. Air is the predominant type in Europe .
4 Trailer brake options are now available.
Even though implement brakes currently are not mandatory in North America, the vast majority of new tractors have a trailer brake option available from the factory. Most companies, including New Holland, John Deere, Case IH and AGCO, offer customers a choice between hydraulic or air on certain models. Depending on the road speed desired, antilock braking systems (ABS) may be required to facilitate steering and braking in bad road conditions, Prouse says (see sidebar).
5 Trailer brakes aid tractor braking.
Implement brakes are designed to aid the tractor in braking when it is heavily ballasted and is pulling a large implement or trailer. Trailer brakes can hold the tractor-trailer train on a steep incline or in the event of a sudden stop, preventing the train from jackknifing.
“Trailer brakes are designed to work with tractor brakes so that when the driver applies the tractor brakes, the trailer brakes come on,” explains Deere’s Herbst. “That braking information goes from the tractor to the trailer, which then goes to a brake or brakes on the axle to slow the trailer down when the tractor brakes are applied.”
Trailer brakes also extend the life of tractor brakes, especially when pulling larger implements and trailers.
6 Uniform systems are the goal.
Standard developers are looking into the different types of trailer brake systems, which use both current and new technology, and are trying to come up with better definitions for tractor, implement and trailer manufacturers to ensure more uniform systems with greater compatibility.
7 Trailer and tractor brakes should match.
Herbst says the biggest item for buyers to determine is what, if any, trailer brakes are available on their implements and trailers and ensure that the tractor has the same type of system. “For example, if the trailer or implement has hydraulic trailer brakes, then a tractor with air trailer brakes will not be very useful,” he explains. “The key is to ensure that the tractor and trailer implement brakes are of the same type.”