Testing, calibration, calibration are carried out on a cyclical basis, static measurement process. The meaning of their respective:
Checking ---- by the legal metrology department or legally authorized organizations in accordance with the verification procedures, through experiments, to provide proof to determine the value of the measuring instrument to meet the specified requirements of the activities of the error.
Calibration ---- in the prescribed conditions, in order to determine the measurement instrument or measurement system of the demonstrated value, or physical gage or standard material represented by the demonstrated value, respectively, using the higher accuracy of the calibration of the standard equipment and the measured equipment to test the same measured object, to get the measured equipment relative to the standard equipment error of a set of operations, so as to get the value of the demonstrated value of the equipment to be corrected value of the data.
Calibration ---- in the absence of calibration or calibration procedures, the enterprise to prepare their own self-calibration procedures. Mainly used for specialized measuring instruments, or relatively low accuracy measuring instruments and test hardware or software.
Since the term calibration is also rarely used in the past few years, so focus on verification and calibration for introduction.
The difference between verification and calibration:
(1) the purpose of different
The purpose of verification is to carry out a mandatory comprehensive evaluation of the measuring device. This comprehensive evaluation belongs to the scope of the unity of value, is the top-down value transfer process. The test should be assessed whether the measuring instrument meets the specified requirements.
This requirement is the measurement of measuring devices prescribed by the error range. Through the test, assess the error range of the measuring device is within the specified error range.
The purpose of calibration is to assess the error of the measuring device against the measurement standard to ensure the accuracy of the value, belonging to the bottom-up traceability of the value of a group of operations.
The evaluation of this error should be based on the organization's calibration procedures to make the corresponding provisions, according to the calibration cycle, and do a good job of calibration records and calibration marking.
(2) different objects
The object of verification is the measurement of China's metrological law clearly stipulates the mandatory verification of measuring devices. Verification of the object is mainly three categories of measuring instruments:
1. Measurement benchmarks (including international measurement benchmarks and national measurement benchmarks).
2. Measurement standards.
3. Measurement law provides for the inclusion of 59 kinds of measuring instruments in the catalog of compulsory inspection.
The object of calibration is a mandatory test outside the measuring device. China's non-mandatory calibration of measuring devices, mainly in the production and service delivery process of measuring instruments used in large quantities, including incoming inspection, process inspection and final product inspection of measuring instruments used.
(3) the nature of the different
The calibration is mandatory law enforcement behavior, belongs to the scope of legal measurement management.
Calibration is not mandatory, belonging to the organization of voluntary traceability.
(4) based on different
The main basis for verification is the "National Measurement and Certification Regulations" (JJG), which is the measurement of equipment must comply with the statutory technical documents. These regulations belong to the measurement of regulatory documents, the organization does not have the right to develop, must be approved by the authorized measurement department.
The main basis for calibration is the organization according to the actual need to develop their own "calibration specifications", or in accordance with the "National Measurement Technical Specification" (JJF) requirements.
(5) different ways
The calibration must be carried out to the qualified measurement department or a legally authorized unit. According to the status quo in China, most production and service organizations are not qualified for verification, only a few large organizations or professional metrology verification department has this qualification.
Calibration can be used to organize the way of self-calibration, external school, or self-calibration and external school combined.
Organizations in the case of conditions, you can use self-calibration of measuring instruments calibration, thus saving greater costs.
(6) the cycle of different
The verification cycle must be carried out in accordance with the provisions of the "verification regulations", the organization can not determine their own. The verification cycle belongs to the content of the mandatory constraints.
Calibration cycle is determined by the organization according to the need to use measuring instruments. Can carry out regular calibration, or irregular calibration, or calibration before use.
(7) the content of the different
The content of the verification is a comprehensive assessment of the measuring device, the requirements of a more comprehensive, in addition to including all the contents of the calibration, but also need to check the relevant items.
Calibration of the content and the project, only the evaluation of the measurement device value error, to ensure the accuracy of the value.
(8) different conclusions
The verification must be based on the "test procedures" specified range of error in the measurement value, to give the measurement device qualified and unqualified judgment. Beyond the "test procedures" specified range of error for the unqualified, within the specified range of error for the qualified. The result of the test is to give the "certificate of conformity".
The conclusion of the calibration is only to assess the measuring device of the measurement error, to ensure the accuracy of the measurement value, not required to give a qualified or unqualified judgment. The results of calibration can be given "calibration certificate" or "calibration report".
(9) the legal effect of different
The conclusion of the calibration has the force of law, as a measuring instrument or measuring device calibration of the legal basis for the "certificate of conformity" is a legally binding technical documents.
Calibration conclusions do not have the force of law, given the "calibration certificate" is only marked quantitative error, is a technical document.
From the above can be seen: verification, calibration, calibration of the three are not completely independent, in the verification and calibration are included in the calibration process, just whether to give the calibration results of the problem.
Checking, calibration, verification of the choice
1. Belongs to the national mandatory calibration catalog to send the inspection, mainly used for occasions with legal requirements. Such as enterprise boilers on the pressure gauge to be sent for inspection on a regular basis.
2. Outside the national mandatory calibration catalog, but there are JJG standards or JJF standards, sent for inspection or calibration, the enterprise has the standard equipment, apparatus and calibration methods, can be calibrated on their own. Mainly used for higher accuracy requirements, or by the conditions, must use lower accuracy measuring instruments for higher measurement requirements of the place, which is the most commonly used method of enterprises, such as production equipment on most of the calibration of the instrument.
3. No JJG standard, JJF standard, self-calibration. Mainly used in the absence of calibration procedures occasions or may not be able to fully meet the requirements of the regulations, but can meet the requirements of the use of the occasion. This is also a common method used by enterprises.