Calibrate load gauge

rblunt

Member

R

Join Date

Nov 2013

Location

Canada

Posts

35

• Nov 3, 2014

• #1

We have a gauge that is measuring the force we press with, whats the industry standard way to calibrate it? Our press gauge is capable of 11240 lbs.

 

danatomega

Lifetime Supporting Member

D

Join Date

Mar 2011

Location

Dayton OH

Posts

789

• Nov 3, 2014

• #2

If you have the load cell calibration sheet available and the calibration procedure for the signal conditioner and you work out the math and you can use shunt calibration method on your signal conditioner, that's the way I have and do perform calibration on all the load cells I have used.

 

rdrast

Lifetime Supporting Member

Join Date

Apr 2003

Location

South Carolina Lowcountry

Posts

5,544

• Nov 4, 2014

• #3

We use NIST traceable weights for all of our load cell calibrations.

 

JRW

Member

Join Date

Jun 2002

Location

South Carolina

Posts

2,301

• Nov 4, 2014

• #4

I will drive down toward Charleston to see 11000 lbs of NIST weights.

 

shooter

Member

S

Join Date

Sep 2002

Location

duketown

Posts

2,711

• Nov 4, 2014

• #5

with a traceable check gauge (just a simple big gauge that is calibrated.
or with a pressure calibration tool (it has a piston and you put weights on it, to getinto the range needed, if the weights are floating you can calculate the pressure from a table.
(i do have one without weights from DRUCK)

 

danatomega

Lifetime Supporting Member

D

Join Date

Mar 2011

Location

Dayton OH

Posts

789

• Nov 4, 2014

• #6

Another way I have used is a calibrated (by an outside firm) load cell that you put into the process and then load it up and compare the readings.

 

rdrast

Lifetime Supporting Member

Join Date

Apr 2003

Location

South Carolina Lowcountry

Posts

5,544

• Nov 5, 2014

• #7

JRW said:

I will drive down toward Charleston to see 11000 lbs of NIST weights.

Click to expand...

We have two steel pallets of 6 1000 pounders each, and then other breakdowns of 500, 250, 100, 50, 20, 10, 5 and 1 pounders. We need them to calibrate everything from large shipping scales to small ingredient weigh systems.

How else would you calibrate 5+ ton shipping scales?

The actual container for each group of 6 1000 pounder really isn't that big, the weights themselves are about a 14" cube with an attachment hook.

Here you go for some specifics:
http://www.scalesgalore.com/Rice_Lake_Class_F_Grip_Cast_Iron.cfm

 

Last edited: Nov 5, 2014

JRW

Member

Join Date

Jun 2002

Location

South Carolina

Posts

2,301

• Nov 5, 2014

• #8

I looked at the link
Those are some massive weights. Thanks for the info

 

rblunt

Member

OP

R

Join Date

Nov 2013

Location

Canada

Posts

35

• Nov 25, 2014

• #9

I was told incorrectly, we have 4700lbs is the maximum according to ballscrew guys.
So the plan is to take a nitrogen spring, squeeze it with hydraulic press which has a gauge and then go push it with our actuator and equate the strain gauge reading to push applied.

Still not sure exactly if this is good enough because I'm relying on the hydraulic press gauge to be accurate.....

 

rootboy

Lifetime Supporting Member

Join Date

Jan 2004

Location

Tennessee

Posts

1,375

• Nov 25, 2014

• #10

rblunt said:

We have a gauge that is measuring the force we press with, whats the industry standard way to calibrate it? Our press gauge is capable of 11240 lbs.

Click to expand...

None of our stuff has to be certified for trade so that makes things simpler. If yours doesn't, then I wouldn't worry about NIST certified weights.

Going with that assumption, I recommend that you use what you have available, and check your results against your process.

Personally, you are better off with a reasonably simple procedure that checks your calibration that you can do on a regular schedule (to watch for drift), than a complicated procedure that only gets done when you suspect that there is a problem.