Reclaim Mode Drawing & Case study on YouTube Animation Video

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I’ve seen an animation in the YouTube on reclaiming operation by a bucket wheel reclaimer machine. The animation is very good, but the reclaimed portion of the stockpile is not represented correctly in the animation.
Before looking into this, I just want to explain THE RECLAIM MODE DRAWING ie., HOW A BUCKET WHEEL STACKER CUM RECLAIMER RECLAIMS THE STACKED MATERIAL FROM THE STOCKPILE. This will make you to understand the wrong representation of the reclaimed stockpile portion in that animation.
(It is not ethical to give the YouTube video/link in this blog, since the YouTube video contains the company logo also. For your reference, I’ve just shown the screen shot from the video WITHOUT the company logo)
Consider the stockpile (& other parameters) we have discussed in one of the previous articles (titled “Trapezoidal stockpile Vs Trapezoidal stockpile”).


Machine                       -       Bucket wheel stacker reclaimer (BWSR)
Boom length                 -       41m (machine axis to bucket-wheel centre)
Bucketwheel diameter    -       8m
Rail gauge                    -       8.2m
Rail to Stockpile            -       2.5m
Tripper length               -       Approx. 60 m (machine axis to tripper end)
Stockpile length             -       300m
Stockpile height             -       10m
Stockpile width              -       40m
Material                        -       Coal
Repose angle                -       37°

RECLAIM MODE DRAWING:
The height of the stockpile is 10m & the bucket wheel diameter is 8m. The maximum allowable bench height for reclaiming is 50% (in some cases 60% also, but generally not advisable) of bucket wheel diameter. Hence for the 8m diameter bucket wheel, the maximum bench height shall be 4m. To divide the stockpile with equal bench heights a bench height of 3.33m is chosen.

CASE 1: Reclaiming from a stockpile formed by compensating the travel length




CASE 2: Reclaiming from a stockpile formed without compensating the travel length




In both reclaim mode drawings it is clearly shown that it is possible to start the reclaiming operation ONLY from the end of the stockpile (which is opposite the tripper side of the machine) and NOT from the middle of the stockpile. Hence the reclaimed portion shall be in the form of a quarter circle and can never be a half circle.

But in the photo, which is a part of the YouTube animation video (refer below) the reclaimed portion is shown as half circle, which is not possible hence it is not correct.



ADDITIONAL INFORMATION:

The below photograph has been taken by me during one of the site visits. Although it is possible for the operator to reclaim the material from the stockyard as shown in the below photo (in manual mode operation), IT IS NOT ALLOWED to do so (kindly write me to know the answer for the question, ‘WHY IT IS NOT ALLOWED’?).




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Comments

  1. Unknown4 April 2018 at 23:30

    Thanks for your Explanation given in Simple manner. ... I would be happy if you could Explain about Advantage of Reversible BWSCR, Where i believe the purpose can be attained with Uniu Directional BWSCR Itself. ... If possible please post an article about this...

    ReplyDelete
    Replies
    1. Basics in Stacker Reclaimer6 April 2018 at 02:06

      There shall be an article on Unidirectional BWSR Vs Bidirectional BWSR shortly.

      Delete
  2. Unknown4 April 2018 at 23:45

    About the Reason for NOT ALOWING RECLAIM IN MANNER Shown... I presume that Blending Sequence get affected and more over Not economical due to more repeated long travel requirement...

    ReplyDelete
    Replies
    1. Basics in Stacker Reclaimer6 April 2018 at 02:14

      In a day or two I shall write a small article which gives the answer.

      (By the mean time kindly note that this has to do nothing with BLENDING. Also please don't get the term BLENDING into picture while reclaiming with a Bucket Wheel type machine. This term is mainly applicable when you use the following Reclaimer Machines viz., Portal/Side Scrapper/Bridge/Barrel. Already planned to write an article on Stacking/Blending. This article will be published after I write an article on Unidirectional BWSR Vs Bidirectional BWSR)

      Delete
    2. Basics in Stacker Reclaimer15 April 2018 at 07:57

      Refer the below mentioned post for detail.

      https://basicsinstackerreclaimer.blogspot.com.au/2018/04/reclaiming-operation-vs-machine-operator.html

      Delete

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