Primary and secondary scrapers should always be external: working on the dirty side. For the cleaner in question do you mean a rotating brush or a spiral drum?

But what is the all important moisture content? According to the presence of 2 scrapers already it sounds wet...but how wet?

Your belt is slow enough to be Anglo American Standard and a spiral drum would be as much use as a chocolate teapot at 1.2ms^-1 so I guess you must be talking brush which will be OK and perhaps deflect the debris to the chute. If 2 sets of blade are not doing the job properly it might be better to throw one of them out temporarily so that you can fit the brush in the first place. ■

Dear Mr.Vinay H Patel,

I have experience with rotary brush scrappers. The fines are getting clogged among the bristles. After sime time, the rotary brushes become like a pulley and become ineffective. I had to remove them and replace them by conventional scrappers.

Now a days, there are many manufacturers supplying conventional scrappers, in two statges ; Primary & Secondary.

These are better than rotary brush scrappers. Please go only for reputed manufacturers.

Regards, ■

Hello John, how is the weather on your side of the pond?

We are getting a warm up by saturday.

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Namaskar,

Wet dirty belts are a nasty messy thing to deal with and are the devils work,

both john Gately and Sganesh offer much insight and

experience.

Short of a high volume high pressure air knife to blast the

material off the carrying side a single counter weighted rubber scraper

is about the only true option you have. BUT if the chutes are enclosed either method

will get very messy, very messy and become hard to clean if left to pile up. ■

Hello,

Rotary nylon brush as an external scraper, and is a well known item, but seems to be less in use. If the material is dry, then it will clean the belt in a manner similar to boot polishing by rotary brush. The belt cleaning would be absolute, provided the material is non-sticky.

In one of the project, this item was used as per buyer's specifications in few fertiliser plants in India. The feed back was as below:

- Fertiliser due to its some hygroscophic nature clogged between the bristles, turning them into solid cylinders, particularly in monsoon.

- Bristles wear was comparatively more.

You may try for more feed back from users, or opt for it because it is not going to stall the plant operation, during remedial measures.

Ishwar G. Mulani

Author of Book : Engineering Science And Application Design For Belt Conveyors (new print November, 2012)

Author of Book : Belt Feeder Design And Hopper Bin Silo

Advisor / Consultant for Bulk Material Handling System & Issues.

Pune, India.

Tel.: 0091 (0)20 25871916

Email: conveyor.ishwar.mulani@gmail.com

Website: www.conveyor.ishwarmulani.com ■