Good hopper design is essential for a successful vibrating pan feeder installation. A fair start to some essentials of the hopper geometry can be found at http://www.jeffreycorp.com/feeders/HopperGuide.cfm ■

John's reference is excellent from the JEFFREY company experts in feeder and hopper design.

When hopper is built above, one of the keys is to design the feed hopper in such a way that the material is controlled exiting the hopper. If opening is too large and material is somewhat spherical or rounds........there is no FLOW CONTROL.....and this of course is a problem.

Jeffreys.....design template is excellent especially in regards to their style of feeders....electromagnetic usually at 10 degree decline from horizontal.

BUT, say on a BRUTE FORCE VIBRATING GRIZZLY FEEDER type of setup........typically the hopper above would be fairly oversize in a primary feeder to a primary crusher situation for example. There would be a very wide range of materials being dumped into the hopper say by 40ton MINING TRUCKS and in that situation you could have 24"-36" topsize ROCK down to fines.......and the material must be slowed down.....after being dumped.....so typically people install ANCHOR CHAINS hanging in the hopper to slow the foot travel rate.....or old MINING TIRES hanging in the hopper or old JAW CRUSHER PLATES......to slow the stone down.

APRON FEEDER.......same type of theory.......just a different method of moving the material by chain drive and cleated heavy duty grouser pad type of plates.

George Baker ■

I have experienced problems with vibrating feeders under hoppers while handling moist earthy hematite iron ore. Reciprocating plate feeders or apron feeders have worked well. ■

Hi Friends,

It's bal;ance betweem initial investment and operating cost.

Probably vibrating feeders have less initial investment and operating cost compared to apron feeders and reciprocating plate feeders.

When installing vibro feeders one should consider concentrated l;oad coming on the feeder and angle of repose of the material. If the material is cascading till the opening of the hopper then surely it's a big problem while starting the feeder as the lumpy stones will touch the upper plate of the opening thus transmitting vibrations to the hopper. It all depends upon the design of the hopper and very less on the type of feeders.

regards, ■

With a BRUTE FORCE vibrating feeder......stopping with a load on it is not desirable.......but, we all know happens.

Basically, the drives are VSD.......VARIABLE SPEED DRIVES.....style as operators generally need to slow down or speed up according to what they are viewing in the hopper.

1. Should really never stop the feeder with a load on it if possible......better to dial down the speed control (potentiometer) and let the feeder rotate with heavy load on it say at plus minus 400 rpm range, then when ok to go again......dial back up to 795 rpm or whatever your normal operating speed is for that feeder device.

2. Important to OVERSIZE the drive motor calculation to take into account START AMP DRAW.....to pull the heavy side of the shaft over from say the 6 oclock or down position. Need extra HP or use of high torque motor to start then,,,, will operate typically on plus minus half of those AMPS.

3. a BIG VGF will typically WALK OUT......be a bit of a HARD possible SLIP START.....put generally will startup if belts have not already been PRE-stretched from prior slipping situation.

George Baker ■

A brute force feeder is an option, but dual mass feeders work alot better, and can do twice the work of a brute force feeder with half the horsepower. One such feeder is the Paramount II from General Kinematics Corporation...

http://www.generalkinematics.com/pro...rs/feeders.cfm

A better option is a device from the same company called the Uncoaler Activator Feeder. The Un-Coaler combines the performance of vibratory feeding with the benefit of integrated flow control...

http://www.generalkinematics.com/pro...r/uncoaler.cfm ■

Fabio: I pic is worth a thousand words.

Snap a digital and attach it here.........and we can see the problem easily.

Thanks George.

My understanding is a typical BIG hopper, typically dump fed by mining trucks......with the LIVE BOTTOM being a vibrating brute force feeder. NOTE: a brute force feeder can and are used in thousands of locations in this exact type of application AND....apron, or texas chain type heavy duty type CLEATED grouser pad type feeders are also extremely common.

IT is simply as choice as to HOW much maintenance you want to do with either type of feeder.....THEY ACTUALLY BOTH WORK successfully. I have seen many in my travels into mining sites and blast rock quarries.

George Baker CIAO ■

This could be any manufacturer's VIBRATING BRUTE FORCE FEEDER in this location.

Many quality manufacturer's to choose from worldwide.

This pic shows a very large open topped DUMP HOPPER which in this instance would be 40-50 ton terex trucks DUMPING into a large hopper which feeds a big JAW CRUSHER.

The customer installed a large cross beam IN hopper here to slow the velocity of the BIG ROCKS in the blast rock feed down prior to getting to MR JAW CRUSHER. other people put in big mining tires or hang heavy anchor chain across hopper width to slow the speed of the rock tumbling off the trucks down.

This pic also shows a breaker installed to break JAMMED rocks out.

This VGF here IS 51" wide x 24' long with PAN and GRIZZLY setup.

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beam in feed hopper (JPG)

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This can be an APRON feeder in this same location, but more maintenance intensive.

MORE subject to abuse

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dump hopper in blast rock operation (JPG)

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apron feeder pic for the alternate choice

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apron feeder (JPG)

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An apron feeder will NOT JAM.......because unlike a BRUTE force PAN GRIZZLY FEEDER.....THERE are no grizzly openings for the elongated carrot shaped rocks to JAM into.

Thee apron feeder simply moves the material from point a to point b MECHANICALLY.

*BUT, you can have JAMS ontop of an APRON FEEDER...By putting TOO BIG of BLAST ROCK into the hopper that JAMS between the stationary sidewalls of the hopper AT the feeder sides....this can be overcome by ensuring the rock being brought up on the trucks is not OVER the size recommended by the FEEDER SUPPLIER. I had this exact problem down east in CANADA. We sized a big VGF for an installation for mostly 36" topsize material and thee occasional 48". When I was there commissioning the unit....they were dumping 6' topsize into the hopper and JAMMING between the stationary liner plates.

..........

On a BRUTE FORCE FEEDER.......you can eliminate the GRIZZLIES no problem...and put all blasted rock direct into the CRUSHER. No more jams......speeds up the process.......many many people go this route to avoid jams. It is called a BRUTE FORCE PAN FEEDER...If you have a grizzly pan feeder combo now.....just weld 3/8" or 1/2" plate overtop....to eliminate the grizzly aspect. ■

Two mass feeders can be built to any size... we recently built one for dewatering coke that was 30' by 16' and had two 5 hp motors on it... they are extremely efficient, and do not dampen out when overloaded like brute force feeders.

Thanks! ■

is that a typo error??? 30' wide x 16 ' long? OR? ■

16' wide, 30' long... we are quoting a 60' long unit now for a different application, also with a two mass feeder drive. ■

JVI offers a unique vibratory feeder arrangement designed specifically for truck dump or railcar dump station unloading as discussed here. With this type of unit, compaction of the static material in the hopper is avoided. Compaction is a common problem when using belt or apron feeders in this application.

With the TITAN, material is discharged from the front to the back so only free flowing material is being moved.

Check it out. (it shows a video animation of it in action)

href="http://www.jvivibratoryequipment.com/titanheavydutyfeeders.html?utmsource=bulkonline&utmcampaign=titan&utmmedium=forumreply" target="blank">http://www.jvivibratoryequipment.com...ium=forumreply

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extrovib unload animation (GIF)

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Dear Mr. Fabio,

I am providing some general information which may be of help:

1) One has to decide the minimum outlet size of the hopper considering that the material do not form the arch. This means enough opening size to ensure material flow.

2) If the material is lumpy, the arch formation is to be seen in context of cohesiveness of material and also in context of the lump size.

3) Then one has to see what should be the minimum width of vibrating feeder to suit the lump size and flow capacity mtph.

4) Choose the hopper outlet dimension which is largest in satisfying the aforesaid serial no. 1, 2 and 3. This means if hopper outlet size required is 800 mm x 800 mm, but tray width needs to be say 1200 mm, then outlet one dimension would be say 1050 mm etc.

5) At the hopper outlet one has to provide discharge mouth (inclined chute piece) say at 55 degree or 60 degree inclination, and it should have sufficient length so that hopper material do not press directly on the tray. This will give economical vibrating feeder. There are also powerful vibrating feeders (mechanical type) which can directly bear the material load and not only that it imparts agitation in the material near outlet zone to enhance the flowability.

The above is the general reply. For application engineering, more thought and analysis is necessary.

Regards,

Ishwar G Mulani.

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

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 ■