Please tell us what you are screening and macerating.

If I understand your description of your process the mincer is the problem. and the feed through the mincer output is to slow.

It would be helpfull if your screen and mincer was pictured but I think your mincer is flooded from grinding and unable to clear the product; it would be helpfull if you could tell us what the product is: It leads me to belive it is a stoned food product as the sugars in a screened macerated product would behave like this.

the answer may lay in using a bigger mincer with a larger discharge outlet to feed the second screen.

If the screens are at opposite inclines and are operating at the same speed with the same drive unit trying to drive against each other. I would like to know what kind of sceen this as your description of its operation seems wrong. ■

Can you tell me who made your screener?

Can I safely assume it is 316 stainless steel due to its screening a food product?

I think my friend George Baker would agree that it-the screen is out of balance can you obtain stroke checking cards from the screen manufacturer?

Please also check for excess build up of milk powder dust around the screener to check for free movement.

The screener has to be clear of the sides and front and back of the frame allow free movent to work properly.

The other item to check for is orbit of the shaker arm.

Take a paint pen and paint a dot on the exciters on both sides of the screen and when it is operating see if the orbit of the paint dots is perfect-if not you have problems:

It might be that milk powder is binding up against that corner of the screen that is not moving well or the worst may be a bad bearing, bearins or bad spring or springs. A weak spring will allow more movement as well on one side or corner.

If the screener has mounting rubbers on the shaker arms be sure to clean them to allow for free movment of the mounting rubber-beacuse if they are not free to move they will transmit thier energy rather than absorb it where it is.

If you dont mind could you tell me the screen manufacturers name? ■

I would almost bet the other bearings are near their maximium B10 life.

Try painting a dot on the rotating parts as I described to check orbits and I think you will see a problem. ■

1. Was the screener loaded and screening when the left and right side were examined?

2. Check the screener for plumb-use nylon line across the screener frame and the screen deck to examine whether it is parallell from side to side/no twisting from left to right -right to left.

Do you know what a line level is? it is a small bubble level that

will attach to the nylon twine to tell you if it is plumb from left to right and right to left acreoos the top and bottom of the screener.

I would also measure the diagonal distance from one corner to

the opposite corner of the screener frame to make sure the escreener frame is not twisted/racked.

Use the same twine to measure the distance from the opposite corners-if it is even a little off the screen frame may be bad.

I will also recommend you examine the length of the springs as one or more of them may have lost their compressive strength which would throw off the feed where the rest of the springs will try to do the work as the bad one is just limping because of metal fatigue.

If everything is true/components are square then I would reduce the product volume over the screener as you mentioned the product was a bit different this year -I am assuming you are screening whole milk powder.

If one or more beariing housings is hot after running the screener you definetely have bearing problems--

As a rule for good maintenance all the bearings should be changed at one time.

I also am curious if the screener side plates have been examined for cracks as they/the side plates are a haven for sympathetic vibrations and cracking from stress- have any of the major components ever been replaced such as driven shafts?

I am also curious as to whether the eccentric shafts are balanced with weight tape etc. I will research pillet driers further.

leon Z ■

It sounded like something was not right. The motors should be identical with the phase/wiring pairs/voltage/amperage/RPM etc. and direction of rotation as they are only fighting against each other.

As they will do nothing but fight with each other since they are not running at the same RPM and their collective energies are essentially not working in together.

Is it posssible you have one fifty cycle motor and a sixty cycle motor doing the same job? it would explain a lot. If the motors are the same the rotation speed should be the same unless and only unless:

1. the cycle rating of each motor is different.

(a) the motors do not have the same number of windings frm a poor rebuild and possibly bad bearings as well.

2. the eccentrics are not in identical in location on the motor shafts used to power the screener. Please remember that the energy created by the motors turning the weights to throw the screens in orbit are required to do this in tandem at all times otherwise the screen will not work simply because the direction of throw is not linear.

Can I safely assume the throw is intentially up hill on the lower screen due to its opposite angle to improve the cutting of the milk powder?

the weights if any should both be at the six o' clock position at start up and after shut down due to slowing and eventually stop with the weight being heavy and resting at the six oclock position simply from the weight itself or at another position identical to both motors.

Their are many food manufacturing associations that have websites relating to powder products such as powdered milk/creamers/cereals/milk chocolate powders/cocoa etc.

Please check the Vibrating screen maufacturers association web site: they are very informative and provide huge amounts of information on screeens and screening.

before I forget the only place that should have any weight on it is the eccentric attached to the motor and no where else as this will do huge amount of damage-

essentially it would add more weight to a swing and it will want to travel farther and we do not want that at all.

leon Z

<www.vsma.org>

hope this helps. ■

Tone1

I knew it would be easy to find- the rule of thumb for v-belt tension is no more than 1/4 to 3/8" distance when the v belt is pressed with a finger or thumb for proper tension - you can also purchase v belt tension gauges from a motor car repair shops tool seller such as as from Snap On etc.

Before I forget it:

unless you are using Ringfedder locking rings or taper locks to secure pulleys etc:

use plenty of blue lock tite to secure the set screws and be sure to use new keys or replacement key stock to secure the pulleys.

If it has not been done already drill a small hole in the keystock where the set screw is going to be located and this will help hold the set screw point in place.

Be sure to use new set screws for the repair or new taper locks to replace the old ones if that is used as a way to secure the pullies etc.

Much success my freind.

leon ■

Tone1 what type of vibratory system? are they the linear type with solenoid such as the vibrators used in busy bee screeners-I am unsure if they are even made any more.

Or are your vibrators used in a bulk storage vessel(the inverted cone of a bin) for the milk powder prior to packaging? ■

Tone1,

Where is the bearing exactly-inboard our outboard side of the screener?, as in is it exposed while running with out endangering you?

email me at lzaharis@lightlink.com and if the bearing is exposed with in reach I can tell you about a tried but true method that I know-providing the bearing housing is stationary. ■