The sector calibrates the force measurement system of single-axis static test machines, used for tensile and compression tests in accordance with the reference standard UNI EN ISO 7500-1, and of machines used for compression tests on concrete (commonly defined presses) in accordance with the reference standards UNI EN 12390-4 appendix B and UNI EN ISO 7005-1 appendix B.

In addition, the sector performs the calibration of force measuring instruments used as test equipment:

• Transportable hydraulic jacks consisting of a hydraulic piston, pump (manual or electro-hydraulic), and a measurement system, generally a pressure gauge or pressure transducer.

• Uniaxial static testing machines with force indicator not in engineering units but in pressure units/electrical units, or equipped with torque rings (removable or integral to the test equipment and therefore cannot be calibrated separately from the test equipment).

The measurement system can be calibrated partially in accordance with the UNI EN ISO 7500-1 standard.

Together with the Accredia calibrations, the laboratory carries out calibrations whose metrological traceability is guaranteed by the Politecnico Quality Assurance System:

• dynamometers for calibration
• industrial load cells
• weighing scales
• intermediate checks

TEST MACHINES

Instruments in calibration	Measuring	Calibration	Conditions	Measuring range	Uncertainty	Method/Procedure
Metallic material test machines 1	Force		Compression	from 2N to 5000 kN	Class 1	UNI EN ISO 7500-1:2018
			Traction	from 2N to 1000 kN	Class 1
Concrete material test machines1			Compression	from 2N to 5000 kN	Class 1
Certificate delivery time: 20 working days from the execution of the measurements

1) For machines equipped with both analogue and digital indicators, the additional calibration with digital indicator requires the issuance of an additional calibration certificate

TEST EQUIPMENT FOR TENSILE/COMPRESSION FORCE MEASUREMENT OF CONSTRUCTION MATERIALS

Instruments in calibration	Measuring	Calibration	Conditions	Measuring range	Uncertainty	Method/Procedure
Test equipment for force measurement1	Force		Compression	from 2N to 5000 kN	Class 1	UNI EN ISO 7500-1:2018
			Traction	from 2N to 1000 kN	Class 1
Certificate delivery time: 20 working days from the execution of the measurements

1) Relating to: presses for tests on earth and bitumen; presses for CBR (California Bearing Ratio) tests; presses for Marshall tests; presses for triaxial tests; presses for ELL tests (Free Lateral Expansion); pull out; plate holder; hydraulic jacks.

DYNAMOMETERS FOR CALIBRATION

Instruments in calibration	Measuring	Calibration	Conditions	Measuring range	Uncertainty	Method/Procedure
Dynamometers for calibration	Force		Compression	from 2N to 50 kN	Class 1	ISO 376:2011
				from 50 KN to 5000 kN	Class 1
Certificate delivery time: 20 working days from the execution of the measurements

INDUSTRIAL LOAD CELLS

Instruments in calibration	Measuring	Calibration	Conditions	Measuring range	Uncertainty	Method/Procedure
Industrial load cells1 2	Force		Compression Traction (calibration on site)	from 2N to 50 kN	Class 1	UNI EN ISO 7500-1:2018
				from 50N to 5000 kN	Class 1
			Compression Traction (calibration on site)	from 2N to 50 kN	Class 1
				from 50N to 5000 kN	Class 1
Certificate delivery time: 20 working days from the execution of the measurements

1) For industrial load cells, the dynamometers used to perform calibrations are excluded

2) For tensile load cells, the measuring range is to be considered from 1 N to 1000kN

INTERMEDIATE CHECKS

Instruments in calibration	Measuring	Calibration	Conditions	Measuring range	Uncertainty	Method/Procedure
Intermediate checks	Force		Material test machines	(Compression) from 2N to 5000 kN (Traction) from 2N to 1000 kN	n.a.	UNI EN ISO 7500-1:2018
			Building material presses
			Hydraulic jacks
			Torque rings
			Load cells > 5 kN
			Load cells < 5 kN (only on site)
			Additional numerical indicator for the machine and/or press
Certificate delivery time: 20 working days from the execution of the measurements

WEIGHING SCALES

Instruments in calibration	Measuring	Calibration	Conditions	Measuring range	Uncertainty	Method/Procedure
Weighing scales	Weight		CTP/PO.97.001	from 1g to 40kg	Maximum 30g	Internal method. Calibration by direct comparison with sample weight
Certificate delivery time: 20 working days from the execution of the measurements