Hello Greg,

My buddy george will love your posting.

Have you done any maintenance on the screen decks recently that altered thier collective performance?

Are the screens securely fastened to the side frames of the screeners?

If the screen is suspended on cables do the cables need changing? do the turnbuclkles have the same number of threads?

Are the screeners level from side to side-that is a killer if not level from side to side. If not checkk the mounting rubbers for tears and assorted damage/build up.

The same goes for screens suspended with coil springs. have you measured the springs in use to compare them to new ones?

An airbag suspended screen may simply have an airbag with a pin hole leak and it will be unbalanced.

Using the Tyler Screens method (which I absolutely hate anyway);

1. Take a 12 quart bucket of the wet sand you want to screen with no prep-meaning the condition it is before it meets the screen for both the over size and undersize sand.

2. Lift the overfull bucket of sand up to chest level and dump it over completely in one motion, when it stops moving get your protractor and measure the angle of the pile and viola your screen angle for both sizes of sand.

The tyler folks swear by this method and it works apparently as they have hundreds of of installs.

If you overload any screen it will not work very well or become blind-plugging-george baker will tell you that.

Perhaps you are overloading the screen decks with out realizing it.

Wet sand takes a lot of effort to throw, are you maintaining the screens properly-meaning tight fabric, tight v belt drivebelts not overtight as this will effect the screeners operation significantly. Do you clean the shaker arms so there is no build up on the shaker rubbers?

Are the shaker arm rubbers in good condition? if not that will have a huge effect on the throw energy created by the eccentric weights.

Do you have a commisioning stoke card to check the screen stroke/orbit while in full tonnage and empty to compare it to current stroke/orbit ranges for both loaded and empty states?

Are the weights for the eccentrics still attached?

Are the discharge end of the screens hitting/banging against the ends of the frame? Do you have any rubber flaps hanging over the end lips of the screen bottom to improve discharge-not a good idea as it affects screen balance and adds to build up.

A screener should have a clear end opening with the material falling down and away from it

Are the screens frames square(equidistant) measured from corner to corner?

Is the sand being fed equally across the top of the screener-a while ago my dear friend Gary Blenkhorn posted a diagram/manufacturer of a splitter to equalize feed across the top of a screener.

Is there any sand buildup at the bottom or top of the screens?

How much sand is left on/in the screens at the end of the day? This will affect things if you have a lot of clay build up.

We have several spots on the forum describing stroke cards and downloads for same, and you can e-mail my buddy george for a stroke card diagram.

If your screen vendor is still a going concern they should have stroke cards in stock as a matter of course.

Perhaps washing the screens while operating will eliminate the blockages.

As my buddy george says "keep on shakin"

lzaharis ■

first of all: we must confirm what type of vibrating screen you are using now.

1. inclined? shaft thru body circle throw type

2. Horizontal timing gear type

....................

6mm or nominal 1/4" minus is not too bad to screen VSMA chart gives a number of picks that are acceptable.

but, for this lets use 1/4" stroke at 1000 rpm, which is very common setup. And read across to the far right column of the SPEED STROKE SLOPE CHART and its recommends 18-25 deg slope. (standard pick is 20 deg slope)

We must clear the top deck firstly and foremost or we do not get to the second deck screening job.

.....

The 1.25mm is extremely extremely TOUGH for a standard 20 deg circle throw machine. the wirecloth pick should be a non blinding, flexmat type t304 stainless steel wire, special s or d slot configuration. YOU need this to try to avoid plugging which will be kinda normal at a 1.25mm opg cut....and trying to pass a 60 percent portion of the total feed to that 2nd deck. MY MY WHAT DO WE DO.

...............

Give that a spin........see the results......then plan B C OR D would typically be to go to a steeper angle, much finer stroke, J&H or TYLER HUMMER or PEP Varivibe type of screen and this would probably more successful.

So back to the 1 st question.....what manufacture and type is your screener please.

Wishing you GOOD VIBRATIONS....and thankyou for your question. ■