Hi Sandeep:

Here we go, On vibrating screens it is very very important or critical to maintain as much uniform tension in all fasteners holding the screen box together. Huck fasteners originated in the aircraft industry and used their for assured fastening torque values.

Vibrating screen companies like to us HUCK BOLTS for the following reasons:

1. Matched torque values of all hardware on machine

2. Nice tight assembly, running as one vs many different rpms

3. HUCK BOLTS stay TIGHT, they do not back off which at the end of the day is the reason sideplates will crack (movement)

4. Automatic assembly process, no torque wrenches needed

Basically, the gun kinda looks like a Black & Decker drill gun with a special attachment that walks the huck nut up the threads and automatically tightens right up to the sideplate and then automatically snaps off the threaded extension. DONE.

To remove, a single tooth drill attachment is put on the huck nut (white metal) and BITES the nut and splits it off. A new nut and bolt then can be re-inserted. NOTE: if no huck equipment is available in the field - people just use normal grade 5 hardware in lieu of huck bolts.

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standard hardware: In the good ole days, manufacturers would drill TIGHT TOLERANCE REAM FIT HOLES into sideplates. Then, hammer in tight tolerance FINE THREAD GRADE 5 bolts then nut them or double nut them, to try to keep tight.

Today, most companies do not ream fit or use FINE THREAD hardware. Too costly. Basically use coarse thread grade 5 hardware and tighten to industry standard torque value for this spec of bolt.

Using a TORQUE WRENCH to identify the proper torque value would be highly recommended for every bolt put in ...LOTS.

REALITY: People DO NOT USE TORQUE WRENCH, tighten up to VERY TIGHT? and finished.

We end up with UNEVEN torque values all over and this leads to more movement of the sideplates and can lead eventually to cracked sideplate sooner than HUCk system. Lets imagine, 2 people installing and tightening all these bolts. One guy 225 lbs and thee other 180 lbs, no torque wrench, we will have very uneven torque values. When they get tired, still more torque value variances, etc.

The bolts move, oval shape the holes and the more they move the more likely they will BREAK OFF. Not a good thing for Mr. Vibrating screen box to live a long, prosperous life.

HUCK BOLT SYSTEMS are widely used for vibrating screens and widely accepted. You will find many companies that still use standard hardware - personal pref and moderately cheaper.

hope this helps........ ■

easy install, fast

Attachments

closeup huck bolts (ZIP)

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standard bolt arrangement GRADE 5

Attachments

typical bolt torque vaule (ZIP)

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Your technicques described for the coarse grade 8 is actually quite correct. Reality on vibrating screens is.........install new hardware, torque up, run machine for full shift....retorque due to loosening off with vibrating movement. Next day, again usually til torque stays same.

Welding is a sure STOP LOCK EFFECT.

I disagree at all times with reusing hardware at any time. The older gentleman that taught me was strict about this point. DO NOT REUSE old hardware....believed that stretching and abuse occurs and should always start new with all new hardware.

HUCK bolts go in once, automatically rachet up to FIX TORQUE VALUE....DONE. no retorque recommended or even possible.

Thankyou for the imput......excellent information.

George Baker ■

Is it right that both the retorque method and huck bolt workes in fastening the vibrating screen box?

Is the retorque method more cheaper? ■

what do you mean by this? ■

I know most of screen use huck bolts to fasten the screen box.

And I see in this post that there is another way in real application, that is to ¡ install new hardware, torque up, run machine for full shift, retorque, tack weld the nut to the bolt ¡.

I want to know if both method to fasten the screen box is ok, and which one is the cheaper solution. ■

How cheap is cheap?

Huck bolts were derided by a bloke I worked for in South Africa who made heavy trucks. Reaming, shrunk-in bolts were all the rage back then, with Peterbilt & Kenworth fanatics. The chassis makes that have survived in any numbers come from Scandinavia & they are all Huck bolted together. ■

retightening bolted hardware after a day of working under vibrating conditions if a common procedure and recommendation by most vib screen mfrs.

the tack welding into place......NOT so much. We discourage with a vengence any form of heat applied to the sideplate at all....to avoid cracks resulting from heat checks made at time of tack welding.

MY old buddy 73 was a stauch proponent of this. ■