Information Needed About Type of Load Cell To be Used!

projectmc
(not verified)
Posted in: , on 6. Aug. 2002 - 16:23

Hi!

We are students, making a project on powder weighing and packaging machine. We need to know the type of load cell that should be used in weighing.

We are going to weigh the bags. The bags will be filled through a nozzle which in turn will be fed by a screw feeder? We need to get an accurate measurement.

Thanks for your help.

Mechatronics Students

INDIA

Load Cell

Posted on 6. Dec. 2002 - 05:09

How precise do yo need to be?

how much money do you want to spend?

If you are loading trough a nozzle , this means it comes from a pneumatic transport system , right?

You are disengaging in the bag?

you must have sone sort of filter then your measurement is not going to be very good.

then how fast do you have to be?

If you do not have pressure, impact loads , or a need for precission.

Any electronic load cell will do the job, if you can do it yourselves with strain gages remenber to compensate for temperature.

Or use the archimides principle, float the bag in a container within a container with water, keep the tolerances tight but not too tight. and read the water level, if necesary use a sepparate transparent pipe and incline it to amplify the readings.

When you are a student you have to use your creativity not your money, new products are generated this way all the time. The proffeessor gives you a challenge, prefferably he detects a need, you provide your time yoiur hands and your un contaminated minds.

try everything buy nothing.

Good luck

if you need more help e mail me at mflores@tecmen.net

Marco Flores

TECMEN Consultant in: Sponge Iron (DRI) handling Sponge Iron DRI Automated Storage Firefighting and Root Cause Analysis Pneumatic Conveying Consultants Phone 5281 8300 4456.
jeje66
(not verified)

Re: Information Needed About Type Of Load Cell To Be Used!

Posted on 14. Feb. 2003 - 12:41

If you are making a bagging of machine first of all you should consider the necessity to make a gauged weigher. Then you might be using intelligent weighing indicators withse points to control the filling of the bag.

Then you decide whethet the bag filling hopper should be outweighing or the bag should be inweighing. If the filling hopper is outweighing you have the problem that not all indicators are able to support negative weighing. If you are outweighing the bag holding construction might cause a rather high tare weight.

From that perspective you choose your weighing accuracy. Add the total bag weight to the tare weight and divide it by the amount of voltage steps (3000 upto 6000, due to gauging standards) and you find dosing accuracy e. Based on this information you can choose the indicator. There are rather many indicators. Because bag filling can cause forces rectangular to the z-axes beam-cells might be of interest to you.

Choosing indicators you can look after global weighing (PR-1713) or Bran & Luebbe indicators, which are rather expensive. To this indicators a wide range of indicators are available (Revere, Global Weighing etc.) You can look it up on the internet.

Re: Information Needed About Type Of Load Cell To Be Used!

Posted on 31. May. 2005 - 05:45

Dear Student,

The type of load cell purely depends upon the design of the mechanicals of the bagging system & the manner in which the weighing vessel is supported & weighed. This determines the mechanical profile of the load cell, of course the more detail i.e the accuracy class & resolution will all depend on the weighing accuracy & the speed of the bagging machine.

To be simple , a strain guage bending beam type load cell is the most common type of load cell used for such application

We are Mumbai based company manufacturing bagging systems, we could help you with your project. You may contact the undersigned.

P.J.Talreja

Transweigh ( I ) Ltd,

Mumbai,

sales@transweigh-india.com