Leader

Collapse

Announcement

Collapse
No announcement yet.

Park brake test...

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • Park brake test...

    I'm curious to know what you guys do for your "daily" park brake test.
    Do you have an SOP/SOG that defines how you do it???
    Put in gear and if it holds, it's good??? Or do you have a set rpm increase above idle that you use?? Or, a set rpm that you go up to, to see if it holds???

    Here's my problem. The FD engineer took 3 rigs OOS because the park brake wouldn't hold when throttled up to 1,200 rpm's in gear. I was called out to find and correct the problem.

    The FD SOP/SOG is to put it in gear, note the idle rpm, and gradually increase the throttle 200-300 rpm's over idle. If it stays, your good. If it moves, call the shop.

    After a careful inspection and test of the park brakes, all 3 were returned into service without any need of adjustment. And FYI, I am extremely cautious when it comes to brakes on these rigs.

    FM1
    I'm the one Fire and Rescue calls, when they need to be Rescued.

    Originally posted by EastKyFF
    "Firemens gets antsies. Theys wants to goes to fires. Sometimeses they haves to waits."

  • #2
    I always just checked them in gear at idle, never tried to throttle up. Shoot, if you throttle up enough in gear you can overcome the brakes, climb a wheel chock, and go pick up a hamburger at McDonald's, and I've witnessed probies trying to do all three!
    Just a guy...

    Lieutenant - Woodbury, MN FD (Retired)
    Road Captain - Red Knights MC, MN4

    Disclaimer: The facts and opinions expressed above are mine, and mine alone, and are not intended to represent the views of any company I have ever worked for, past or present.

    Comment


    • #3
      Sop

      Our department policy is to park the truck on a slight incline facing down the incline apply the park break and throttle up 200 or 300 rpm above idle. That “above idle” is important because at one point it was written to take the truck up to a set rpm but we were finding a lot of trucks failing because the idled low and any more than that 200 or 300 rpm increase was causing the truck to move. In saying that typically if the truck moves they just put a little bit of a turn on the breaks even thought they might still be in adjustment just to stop the rig from moving.

      Comment


      • #4
        Originally posted by MColley
        Our department policy is to park the truck on a slight incline facing down the incline apply the park break and throttle up 200 or 300 rpm above idle.
        Our FD's SOP/SOG for going 200-300 rpm's over idle on level ground, is to substitute the parking on an incline. Either facing downward or upward.

        I'm astonished, yet surprised at the none responses from others.

        NOTED.

        FM1
        I'm the one Fire and Rescue calls, when they need to be Rescued.

        Originally posted by EastKyFF
        "Firemens gets antsies. Theys wants to goes to fires. Sometimeses they haves to waits."

        Comment


        • #5
          I don't think throttling up a certain number of RPM's to check is the right way to do it.

          One truck may have a 450 HP engine and 6.14:1 ring & pinion gears. A truck like that would climb trees as long as it had traction. While another truck may have a 325 HP engine and 4.88's.

          I can tell you what the NFPA manufacturer's test is, which you likely already know. The parking brake is supposed to bring the fully laden vehicle to a complete stop from a speed of 5 mph within 20’.
          The American people will never knowingly adopt Socialism. But under the name of 'liberalism' they will adopt every fragment of the Socialist program, until one day America will be a Socialist nation, without knowing how it happened. --Norman Mattoon Thomas, 6 time presidential candidate for the Socialist Party of America

          Comment


          • #6
            Originally posted by FIREMECH1 View Post
            I'm astonished, yet surprised at the none responses from others.

            NOTED.
            We don't do a dedicated brake test at our department. In fact, I feel somewhat ashamed that in my many years of doing this for a lot of different departments, that I've never heard of anyone doing a brake test.
            Career Fire Captain
            Volunteer Chief Officer


            Never taking for granted that I'm privileged enough to have the greatest job in the world!

            Comment


            • #7
              Originally posted by BoxAlarm187
              We don't do a dedicated brake test at our department. In fact, I feel somewhat ashamed that in my many years of doing this for a lot of different departments, that I've never heard of anyone doing a brake test.
              Seems like you're not the only one that doesn't do it, or has never heard of it. I thought it was something every department did. (???)
              Maybe it's something our FD decided to do, to make sure the spring brakes will hold on the hills. Not sure why it's in their SOP/SOG, but it is.

              FM1
              I'm the one Fire and Rescue calls, when they need to be Rescued.

              Originally posted by EastKyFF
              "Firemens gets antsies. Theys wants to goes to fires. Sometimeses they haves to waits."

              Comment


              • #8
                Originally posted by FIREMECH1 View Post
                Seems like you're not the only one that doesn't do it, or has never heard of it. I thought it was something every department did. (???)
                Maybe it's something our FD decided to do, to make sure the spring brakes will hold on the hills. Not sure why it's in their SOP/SOG, but it is.

                FM1
                I have heard of it, but we don't do it or have a policy for it. It is not a bad idea.

                Comment


                • #9
                  Some CDL parking brake (spring brake) tests reference rolling at low speed and setting the spring brake. This test specifies a minimum braking rate of 12% of gravity. Since "G" is 32 ft/sec*sec. This is 3.84 ft/ sec * sec. Rolling at 5 mph is 7.33 ft/ sec so stopping should be accomplished in 1.909 seconds. Assuming a uniform decileration rate, the rolling distance after the brake starts dragging will be (7.33 / 2) * 1.909 = 6.996 ft. But you must only start measuring after the brake starts to apply, not when you pop the yellow button. Another way to test would be to stop on a 12% grade, set the spring brake, and see if the truck stays still.

                  Comment


                  • #10
                    Originally posted by txgp17
                    I don't think throttling up a certain number of RPM's to check is the right way to do it.

                    One truck may have a 450 HP engine and 6.14:1 ring & pinion gears. A truck like that would climb trees as long as it had traction. While another truck may have a 325 HP engine and 4.88's.

                    I can tell you what the NFPA manufacturer's test is, which you likely already know. The parking brake is supposed to bring the fully laden vehicle to a complete stop from a speed of 5 mph within 20’.
                    Yep, I know what the NFPA standard is set to. But that 20' is too long in my opinion. If push comes to shove with those that think they know, I do a 5mph test. If it doesn't stop in 3 seconds from popping the valve, then we MAY have a problem.

                    As for HP and rear gearing, that issue is really not an issue. I've got a rescue/hazmat 500HP with 5:37 gearing on a single axle, and does OUR park brake test just fine.

                    FM1
                    I'm the one Fire and Rescue calls, when they need to be Rescued.

                    Originally posted by EastKyFF
                    "Firemens gets antsies. Theys wants to goes to fires. Sometimeses they haves to waits."

                    Comment


                    • #11
                      Originally posted by FIREMECH1 View Post
                      As for HP and rear gearing, that issue is really not an issue. I've got a rescue/hazmat 500HP with 5:37 gearing on a single axle, and does OUR park brake test just fine.
                      FM1
                      Yes,
                      A parking brake that can resist your test with the 500/5.37 combo is a good example of a good parking brake.

                      However, a 350/4.88 combo would exert much less torque on the wheels. So a weaker parking brake on that truck MIGHT pass that test, but not hold adequately on a steep grade. Emphasis on MIGHT.
                      The American people will never knowingly adopt Socialism. But under the name of 'liberalism' they will adopt every fragment of the Socialist program, until one day America will be a Socialist nation, without knowing how it happened. --Norman Mattoon Thomas, 6 time presidential candidate for the Socialist Party of America

                      Comment


                      • #12
                        When I do my weekly pre-trip of the trucks (The pre-trip that is defined in the Vermont DOT CDL manual) I rev the engine to 1,000 RPM's, and if it holds it passes its inspection. If it moves, well I recommend it taken out of service.

                        That's how I do it with all the big vehicles I drive, our rigs at the station, my 02' International box truck at Budweiser. And whichever school bus I happen to be driving on the weekends.
                        Opinions expressed by myself here are just that, mine. And not that of ANY organization or service I am affiliated with.

                        Comment


                        • #13
                          Originally posted by BoxAlarm187 View Post
                          We don't do a dedicated brake test at our department. In fact, I feel somewhat ashamed that in my many years of doing this for a lot of different departments, that I've never heard of anyone doing a brake test.
                          Remember, disaster begats code. Those departments with a parking brake testing policy, procedure, guide, etc. are probably those who have had an apparatus roll away with the brake set. Just sayin'

                          Comment


                          • #14
                            Originally posted by LFD2203 View Post
                            Remember, disaster begats code. Those departments with a parking brake testing policy, procedure, guide, etc. are probably those who have had an apparatus roll away with the brake set. Just sayin'
                            My wife's car was crushed (it was parked) by a 3000 gal FD tender that rolled out of the auto body shop.

                            Of course, the parking brake wasn't set. A critical step in the process.
                            I am now a past chief and the views, opinions, and comments are mine and mine alone. I do not speak for any department or in any official capacity. Although, they would be smart to listen to me.

                            "The last thing I want to do is hurt you. But it's still on the list."

                            "When tempted to fight fire with fire, remember that the Fire Department usually uses water."

                            Comment


                            • #15
                              Originally posted by LFD2203
                              Remember, disaster begats code. Those departments with a parking brake testing policy, procedure, guide, etc. are probably those who have had an apparatus roll away with the brake set. Just sayin'
                              Nope, not here. It is something called being "PRO-ACTIVE", than being RE-ACTIVE. Some should study the difference. 'Just sayin'

                              FM1
                              I'm the one Fire and Rescue calls, when they need to be Rescued.

                              Originally posted by EastKyFF
                              "Firemens gets antsies. Theys wants to goes to fires. Sometimeses they haves to waits."

                              Comment

                              300x600 Ad Unit (In-View)

                              Collapse

                              Upper 300x250

                              Collapse

                              Taboola

                              Collapse

                              Leader

                              Collapse
                              Working...
                              X