E2 stainless steel calibration weights – Reference accuracy for Class I metrology
The E2 class stainless steel calibration weight series meets the most stringent accuracy requirements in metrology. These weights are specifically designed for the calibration of F1 class weights and for use with Class I weighing instruments in special precision applications, such as in calibration laboratories, research centres or regulated industries.
Compliant with OIML R111, the weights in this series are manufactured in a single piece, i.e. made from a single piece of stainless steel with no adjustment cavity. This design choice guarantees perfect mass homogeneity, with no internal imbalance, which limits the risk of drift over time and increases dimensional stability.
Each weight is carefully identified to enable full traceability, which is essential for metrological accreditation or standardised quality processes. In accordance with the OIML recommendation, weights or sets of weights in class E2 must be accompanied by a calibration certificate attesting to their metrological conformity and traceability to a national or international standard.
The physical performance of these weights is based on strict characteristics. The material used has a density of 8000 ± 60 kg/m³, which ensures optimum structural stability. The very low surface roughness ( Rz < 1 µm, Ra < 0.2 µm) reduces particle adhesion and allows for easy maintenance. Permanent magnetisation is less than 8 µT, and magnetic susceptibility remains extremely low (less than 0.9 for m < 1 g; < 0.18 for 2 g ≤ m ≤ 10 g; < 0.07 for m > 20 g), ensuring reliable weighing even in sensitive environments.
Typical applications for this series include the calibration of high-precision measuring instruments, the verification of secondary standards or measuring chains, and quality assurance in the pharmaceutical, food, aerospace and electronics industries.
The weights are handled with care appropriate to their level of precision: gloves must be worn, they must be protected from thermal or mechanical shocks, and they must be stored in closed cases. Their cavity-free design simplifies maintenance and provides better protection against environmental influences. Their rigorously defined geometry ensures safe and reproducible handling.
This series offers complete coverage of values from 0. 1 g to 20 kg, allowing adaptation to different types of analytical or semi-micro balances and to all load levels commonly used in internal verification or calibration protocols.
