Scissors Vs Clam

TOR
(not verified)
Posted in: , on 18. Feb. 2004 - 10:58

Hi

we are in the alumina business and are looking for a performance improvement from our grab ship unloader. There appears to be alot of opinion regrading the relative merits of clam shell and scissors grabs. Would anyone have hard data comparing the maintenance costs, rope wear, trimming times etc between the 2 types? Or even for the operation of one type which you feel is successful for you!! There doesnt appear to be any tech. papers available on this subject

Thanks

Re: Scissors Vs Clam

Posted on 18. Feb. 2004 - 06:14

Dear Mr. TOR,

I do not have first hand experience on the subject, however, this information is from the book Stacking, Blending, Reclaiming of Bulk Materials edited by Dr. R H Wohlbier, TransTech Publications, Germany.

Following are some of the key observation on this topic :

1) Scissor type bucket has more digging force for the same weight of bucket.

2) Scissor type bucket is lighter for same capacity. Alternatively, bucket of same weight will have more load carrying capacity with scissor type bucket i.e. more unloading capacity of the system.

3) The article also mentions certain limitations in use for scissor type bucket and certain disadvantages.

I suggest you to refer this book chapter number 45 for more information and interpretations as per you.

Regards,

Ishwar G Mulani.

Author of Book : Engineering Science and Application Design for Belt Conveyors.

Email : parimul@pn2.vsnl.net.in

Tel.: 0091 (0)20 25882916