Is your request for electric vibration or air vibration and if either one is suitable, please indicate 1-phase or 3-phase and if air do you have enough air capacity. It will make a difference. If you fax a sketch to 508-883-9978, we can fax back showing which vibrator and how to mount the vibrator?

Chamberland Engineering ■

Dear Mr. Venkat,

As you are designing the screen you might have already fixed / decided the amplitude and frequency of vibration to suit the screening function. Subsequently, the type of vibrator will mostly depend upon the above parameters and whether you need circular / elliptical / straight line vibration.

Regards,

Ishwar G Mulani.

Author of Book : Engineering Science and Application Design for Belt Conveyor

Email : parimul@pn2.vsnl.net.in ■

This is a very interesting question. First, prior to making a recommendation on the type of vibrator. One must determine what we are screening (material) and at what opening.

This will in fact DICTATE the type of vibration mode whether that be:

1. A shaft thru body style vibrator with a concentric shaft and eccentric hub ........or also know as a CIRCLE THROW MACHINE typically at a 20 degree installation angle to help the material move with the help of the vibrating shaft assembly.

THIS WOULD BE a concentric shaft design, typically with a Couple of COUNTER weighted FLYWHEELS on either side "weighted" to allow the amplitude or size of the circle to be increased or decreased by adding or subtracting plate weights.

2. A overshaft or shaft thru body TWIN SHAFT GEAR DRIVEN vibrator assembly could be used depending on the type of material desired to be screened. The advantage of this style is low head room to accomodate portable equipment designs.....so the unit can go down the road and make it under bridges and such. Typically 13.5 FEET or at least under 14 feet normally.

Depending on the application........ie DEWATERING OR DRY screening.....the material will "see" a full opening in the wirecloth because it comes directly OVER IT........vs the CIRCLE THROW design.....where the material ......sees a "foreshortened opening" due to the screen being installed at 20 degree incline. We can normally cheat up a 1/16th of an inch and still make a spec product.

3. INVICTA MOTOR DESIGN: This can be used as a more simple drive design....either on CIRCLE THROW installations or HORIZONTAL installations. If a heavy duty job, I would personally stay away from this. Easy to adjust with pie weights on one to ten settings to make more or less ACCELERATING FORCE.

4. You MUST HAVE A vibrator assembly THAT will accomodate two things...................ONE........move the actual static body weight.....and TWO......stroke or stratify the coarse fraction of the material up in the air at the PROPER height to allow the fines to pass the screen cloth opening.

5. Question: What screencloth opening are you screening at?

How many tons per hour desired?

One or two deck screen box design?

What is the size of the conveyor device feeding it?

George Baker, MODERATOR ■

Adding a Small Point:

There are diferring methods of feeding. Direct feed from the conveyor will reduce the screening efficiency. The material needs to be uniformily distributed over the screen width prior to placing material onto the screen cloth. DEM modeling shows the benefit and practice verifies it.

Lawrence Nordell

Conveyor Dynamics, Inc.

www.conveyor-dynamics.com ■

I know you are trying to make contact with us, however we are unable to contact you. Please ither eaml us direct at vibrate020@aol.com or fax us at 508-883-9978 and we wil make contact with you. You have tried two time and we can't get through to bulk on line suggestions.

David Chamberland

Chamberland Engineering ■