Testing/
Calibration
Weighing Technologies, Inc. provides calibration services to our clients which are in strict accordance with ISO 17025-2017 calibration procedures. Being ISO 9001 Certified with ISO17025-2017 Accreditation assures you that we are bound by management practices to providing only the very best quality to our customers. We currently provide service for companies in a wide variety of industries: Truck Scales, Railroad Track Scales, and High Precision Balance Calibration.
TRUCK SCALE CALIBRATION AND CERTIFICATION PROCEDURE
- A visual inspection is made of the entire scale system, encompassing the overall condition of the scale, and any obvious problems are so noted. If problems are minor, they are corrected. Zero and span values prior to calibration are noted and recorded.
- NIST traceable, certified test weights will be applied to the scale, according to NIST Handbook 44 standards in order to check the overall accuracy of the scale system. The reading is, recorded and corrected if necessary.
- Any variances in readings will be adjusted and minor adjustments may be made to bring the scale to within tolerances of NIST Handbook 44 standards.
- A heavy section test with certified weights will be performed and in both directions. Readings are noted and recorded. This test is also done twice and adjustments will be made, if necessary. Repetition of the test assures that we are being thorough with our procedures.
- If all sections are within NIST Handbook 44 tolerances, the technician will then calibrate zero and span values. This will bring the scale to within tolerances set by NIST Handbook 44 standards. If the tolerances cannot be brought up to the standards, the service report “DOES NOT” box relating to the error/application for the scale would be checked.
- A reduction test to 0 pounds will be performed on the scale. Any errors found will be recorded and corrected.
- Zero and span weight reading after calibration are noted and recorded.
- A strain load test will be performed with a test load equal to or greater than 25% of indicated capacity.
- If all tolerances are brought up to standards, a calibration sticker will be placed on the scale indicator showing it to be in compliance.
- The traceability to NIST of the weights used for the service will be noted on the calibration form, along with the last date of certification and the NIST Certificate Number.
A Weighing Technologies, Inc., Service Report form will be completed reflecting the findings of the ISO 17025-2017 calibration procedures and any recommendations. If any recommendations are made that would improve the reliability and accuracy of the scale, they are noted at that time. A copy of the Service Report along with the TRUCK SCALE CALIBRATION REPORT is left with the customer.
RAILROAD TRACK SCALES CALIBRATION AND CERTIFICATION PROCEDURE
Complete a visual inspection of the entire scale system (i.e.: Deck, Suspension, Instrumentation) will be performed and all findings will be noted. Visually inspect all cables, connectors and / or conduit.
- Perform a section test on all section with a Minimum weight of 30,000 pounds.
- Perform an overall calibration test with a Minimum weight of 30,000 pounds.
- Perform a repeatability test on the entire scale system.
- Perform all needed adjustments to the scale system as prescribed necessary.
- A strain load test will be performed with a test load equal to or greater than 25% of indicated capacity.
- If all tolerances are found to be within NIST Handbook 44 standards, a calibration sticker will be placed on the scale indicator showing it to be in compliance.
- The traceability to NIST of the weights used for the service will be noted on the Calibration form, along with the last date of certification and the NIST Certificate Number.
A Weighing Technologies, Inc. Service Report form will be completed reflecting the finding of the calibration procedure and any recommendations. If any recommendations are made that would improve the reliability and accuracy of the scale, they are noted at this time. A copy of this Service Report along with a copy of the Railroad Track Scale Calibration Report is left with the customer.
HIGH PRECISION BALANCE CALIBRATION PROCEDURE
A visual inspection is made of the overall condition of the balance, and any obvious problems are so noted. If problems are minor, they are at this time corrected and recorded on the calibration form.
- Zero balance reading is recorded.
- NIST traceable certified test weights are applied to all corners or load points of the unit and readings are recorded. If errors are found, they are corrected at this time.
- NIST traceable, certified test weights will be applied to the balance according to NIST Handbook 44 standards in order to check the overall repeatability of the balance. The readings obtained are recorded.
- Any variances in the readings are adjusted to bring the balance up to NIST Handbook 44 standards.
- A linearity test is preformed on the balance using NIST traceable, certified test weights. Readings are recorded and errors found are corrected.
- Sensitivity and hysteresis tests are performed and recorded on the service report in a pass or fail fashion.
- If all tolerances are brought up to standards, a calibration sticker will be placed on balance showing it to be in compliance.
- The traceability to NIST of the test weights used for the service will be noted on the calibration form, along with the last date of certification and the NIST Certificate Number. If the tolerances are not brought up to standards, the service report “DOES NOT” box relating to the error/application for the balance would be checked.
A Weighing Technologies, Inc. Service Report form will be completed reflecting the findings of the calibration procedure and any recommendations. If any recommendations are made that would improve the reliability and accuracy of the balance, they are so noted at this time. A copy of this Service Report along with a copy of the High Precision Calibration Report is left with the customer.
