Results 1 to 6 of 6

Thread: 3 Roll bending Machine

  1. #1
    Associate Engineer
    Join Date
    Oct 2011
    Posts
    4

    3 Roll bending Machine

    Recently i had face a problem regarding this 3 roll bending machine. The machine had a center moving roller (y-axis) and two infeed and outfeed roller and is control manually. The machine roller is custom made to fit a moulded aluminum profile, material AL 6061 T4 and T6. How to ensure that the repeatibilty of the aluminum profile is constant in each time bending?
    Thank you...

  2. #2
    Technical Fellow
    Join Date
    Feb 2011
    Posts
    1,043
    To what limits are you talking "repeatability?" If it is guttering then some edge-guide rollers will suffice. If it is 0.005" you are aiming for then you may need some trimming shear-rollers. Is the output straight, curved, ring or what?

    If you provide details we can guide you with details.

  3. #3
    Associate Engineer
    Join Date
    Oct 2011
    Posts
    4
    Thanks for the reply~
    The output is actually straight at both end and curve at the center. 60mm each side of straight section and 90degree bend angle. The thickness of the material is 43mm.
    For the machine, the distance between the two bottom fixed roller is 425mm and had a diameter of 160mm.The center moving roller is custom made according to the aluminum profile shape with diameter 129.4mm. The problem is each time bending, the profile output is not same and need to manually adjust for a long time to get the correct shape.
    So, the repeatability mean that how to get the correct shape everytime after bend?
    Due to the machine is manually control for start stop, is there any idea to get a symetric bend profile?
    How do i calculate the distance to stop the roller?
    Thank you very very much....

  4. #4
    Associate Engineer
    Join Date
    Oct 2011
    Posts
    4
    al profile.jpgroller position.jpg
    The first attachment is the Aluminum profile and second attachment is the roller position

  5. #5
    Technical Fellow
    Join Date
    Feb 2011
    Posts
    1,043
    OK, thanks for more detail, I understand the problem better. Manually stopping and starting is doomed to failure. There are too many things working against you. The start up torque, the carry-on torque at shut-off, rollers slipping on the material. The torque will be dependent on line voltage at the instant of start and stop buttons. Given the manual control you mention, I am guessing that this is very low production levels.

    Depending on the accuracy of the bend angle you require a better approach would be to use something like this...
    http://www.northerntool.com/shop/tools/product_630_630

    One end of the material is held stationary so you are starting from a known position. You would still need to have a contoured form and roller for that extrusion profile.

    The lower ring has holes for a stop-pin. By adjusting the diameter of that pin you can achieve very repeatable angle bends once you have figured out the spring-back etc. I can easily maintain +/- 0.25 degree.

    If you need much higher production levels then look at tubing bending equipment and use contoured forms and rollers.

    I have several other smaller benders, so do some research on Droz and Duo-Mite metal benders. The Duo-mite actually has a clamp to hold the stationary end.

  6. #6
    Associate Engineer
    Join Date
    Oct 2011
    Posts
    4

    Bang Head

    Thanks for the suggestion...
    Yeah~ the production level is low yet need to achieve precision in least time...

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •