Page 1 of 3 123 LastLast
Results 1 to 10 of 26

Thread: Inclined Belt Weigher

  1. Question Belt Weigher

    Hi All,

    Normally the belt weighers / scales are installed in horizontal position only since the calibration is easy..

    I would like to know that whether they can be installed in inclined portion of conveyors? Any suppliers for this? Method of calibration?

    Jigishu Shah

  2. #2
    ignacio rodrigu Guest
    we use Merrick gravimetric scales (weightmeters) for Stacker/Reclamimers boom (45 meters, +12/-16 degres). they use an inclinometer to determ the angle correction factor. They work since 1984 faily well.
    At present we are moving to a non contact type (radiometric or laser scanner) in order to avoid error due to belt conveyor tension change (it use a hidraulic take-up).
    bye

  3. #3
    azabir Guest

    Exclamation

    Dear Mr. Ignacio,

    Could you describe for "gravimetric scales and non contact type (radiometric or laser scanner)" principally.

    Currently, we need the optional scale to measure flowrate for blending purpose and will be placed at Stacker/Reclaimer.

    And then please advise me the supplier/manufacturer web address for subject above.


    Regards
    Achmad Zabir Ula

  4. The belt weigher / scales are regularly installed on horizontal portion or straight incline portion of conveyor. The belt weighers are also regularly installed on straight incline conveyor but varying inclination (like boom of luffing type stacker)

    The Belt weigher cannot be installed in concave / convex portion of belt conveyor, because variation in belt tension will vary the belt pressure (force on idler) and reading will not indicate true weight force (i.e. mass). The belt tension in conveyor continues to fluctuate depending upon instantaneous conveying rate (loading).

    Regards,
    Ishwar G Mulani.
    Author of Book : Engineering Science and Application Design for Belt Conveyors.
    Email : parimul@pn2.vsnl.net.in

  5. Dear Mr. Mulani,

    Thank you for your reply. Can you provide or suggest the method and supplier who is supplying the weigher that can be installed on inclined conveyor.

    We are having the conveyor with fixed inclination of 8.5 and capacity of 400 TPH.

    Rgds,
    Jigishu Shah
    MUNDRA PORT
    Jigishu Shah

  6. Dear Jigishu Shah - MUNDRA PORT

    Please inform your email address to provide you required information.

    Regards
    Ishwar G Mulani
    EmailID: parimul@pn2.vsnl.net.in

  7. #7
    Steve Davis

    Steve Davis, B.Eng., P.Eng., CEng, CPEng, FIMechE, FIEAust

    Technical Director

    WorleyParsons Canada

    WorleyParsons Canada

    Incline weighers

    Many suppliers can offer mechanical (load cell) weighers for installation on straight inclined belt conveyors.
    Like all mechanical weighers they need to be calibrated using a measured quantity of the correct material. OIML R-50 and NIST handbook 44 give some calibration details for certification, which could be adapted for non certifyable use. The accuracy of the weigher will be largely dependant on the quality of the installation of the belt in which the weigher is installed, and the method by which you calibrate.
    There are a variety of weighers available, ie single roll, two roll etc., and some units have been type approved. This information should be available from suppliers.
    Trust this helps

  8. #8
    Ralph Closs - Siemens Automation, Canada Guest

    Re: Incline weighers

    Originally posted by Steve Davis
    Many suppliers can offer mechanical (load cell) weighers for installation on straight inclined belt conveyors.
    Like all mechanical weighers they need to be calibrated using a measured quantity of the correct material. OIML R-50 and NIST handbook 44 give some calibration details for certification, which could be adapted for non certifyable use. The accuracy of the weigher will be largely dependant on the quality of the installation of the belt in which the weigher is installed, and the method by which you calibrate.
    There are a variety of weighers available, ie single roll, two roll etc., and some units have been type approved. This information should be available from suppliers.
    Trust this helps

  9. #9
    Ralph Closs - Siemens Automation, Canada Guest
    Application Guidelines for belt scales ( belt weighers) can be found at this address: http://www.siemens-milltronics.com/p...981GA01.pdfss;

    For a variable incline conveyor, such as a stacker conveyor, an incline compensation device should be used. Siemens Milltronics offers such a device that compensates for angle changes by raising and lowering the belt scale load cell excitation voltage,
    With such a device, it is still important to keep consistent belt tension by using a gravity take-up on the conveyor, if it is all possible.

    Ralph Closs
    Product Manager
    Siemens Milltronics Process Instruments

  10. #10
    Steve Davis

    Steve Davis, B.Eng., P.Eng., CEng, CPEng, FIMechE, FIEAust

    Technical Director

    WorleyParsons Canada

    WorleyParsons Canada
    The milltronics manual gives some good advice on the basics of a belt weigher installation, and many weigher suppliers offer similar advice.

    An issue not covered is that of belt speed used to integrate the weigher output signal into a weight reading. This can be measured several ways, but the norm is either a wheel on the return side belt or a tachometer on a pulley shaft. The wheel method is inherently less accurate for various reasons, but may be acceptable depending on requirements. The pulley tachometer can suffer from inaccuracy due to lagging wear over time, but planned re-calibration will reduce this and most of the other variations in conveyor condition generated with time.

    Installation of a weigher on a variable incline beltwould not be a first choice for ultimate accuracy. The issue being that unless the weigher is calibrated with material at each incline, there is no real way in which the accuracy of the incline correction device, be it electronic or mechanical, can be confirmed. The approximation may be adequate for weighing where ultimate accuracy is not required.

    A straight, horizontal conveyor is preferred for accurate weighing, with the weigher just after the single load point in a well aligned, well founded conveyor with gravity take up. Wind protection fences or a full enclosure also help. A similar fixed straight incline conveyor is likely to be slightly less accurate.

Page 1 of 3 123 LastLast

Similar Threads

  1. Belt Weigher
    By grandhe in forum Weighing, Dosing & Proportioning
    Replies: 15
    Last Post: 26th February 2009, 14:37
  2. Spillage From Inclined Coal Conveyor
    By Steve Cloake in forum Mechanical Conveying
    Replies: 12
    Last Post: 14th December 2004, 6:23
  3. Belt Weigher Inclination
    By Ben Paton in forum Ask Lyn Forum
    Replies: 7
    Last Post: 13th December 2004, 17:12
  4. Belt Conveyors(Steel v/s Nylon belt)
    By Rajesh Mendiratta in forum General Aspects
    Replies: 6
    Last Post: 1st April 2004, 15:28
  5. inclined piping in dense phase pneumatic conveying
    By Mahesh Thota in forum Pneumatic Conveying
    Replies: 2
    Last Post: 6th December 2002, 16:46

Tags for this Thread

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  
Single Sign On provided by vBSSO