Views:28 Author:Site Editor Publish Time: 2020-09-21 Origin:Site
Standard procedures are the basis for testing and judgment. We must adopt multiple channels to collect new standards in a timely manner to ensure that the standard version on which testing is based is currently valid. At the same time, the new and old standards should be analyzed and compared, and in accordance with the new requirements of the standard procedures, Do a good job in the basic work of equipment transformation, configuration, and implementation of new standards. In the aspect of laboratory standards publicity and implementation, we must do a good job in implementation. One is to focus on standard equipment and publicity, and the other is to check and update standards to ensure that the testing work has standards and standards.
The state of the test sample should meet the standard requirements.
(1) The samples should be representative, and sampling should be carried out by random sampling.
(2) The number of samples is related to the accuracy of the test results. If the number is too small, the error caused by the test will increase. Therefore, the standard requires the number of material samples. In actual test work, it is necessary to strengthen the control of the number of tests. If the standard requires parallel tests, the samples should be divided into equal parts and tested separately. If only one test is performed, the data should be put together to report. This is strictly prohibited.
(3) The size of the sample is related to the accuracy of the test results, and the size of the sample must meet the standard requirements.
Instruments and various measuring instruments are the most basic tools in the inspection work. Their integrity and accuracy will directly affect the accuracy of the inspection data and also affect the evaluation of the project quality.
(1) For the control of measurement standard instruments, the establishment, replacement, storage and cancellation of laboratory measurement standard instruments or calibration devices, a complete technical file shall be established.
(2) All test instruments and equipment for compulsory metrological verification specified by the state must be submitted for inspection and timely inspection. After the inspection, the calibrated equipment shall be rechecked to check whether the calibration data meets the requirements for use.
(3) For some test instruments and equipment that are not within the scope of mandatory inspection and the country has not formulated calibration specifications, calibration specifications should be established by themselves in accordance with the instrument manuals, related technical specifications, and related metrological verification procedures, as the basis for regular self-calibration, and control The accuracy of the measurement data.
(4) In addition to verification (calibration), attention should be paid to the regular maintenance and inspection of equipment and various measuring instruments.
Laboratories should establish relevant systems to effectively control the entire process from the purchase, acceptance, storage, distribution, use and disposal of standard materials to ensure the use of standard materials within the validity period and to ensure the accuracy of their values , Uniformity, stability and other measurement performance meet the testing requirements.
Temperature and humidity have a certain influence on the performance of some materials. Therefore, the environmental conditions for material testing are clearly stipulated in the standard and must be observed.
In the material mechanical property testing test, the loading speed has a certain influence on the testing result. Generally, the loading speed is relatively fast, the deformation of the specimen lags behind the load on it, and the measured strength value is higher than the inherent strength of the material. If the loading speed of the downhole tool cylinder is faster, the yield strength and ultimate strength will be improved.
In the test work, repeated tests, comparison tests, proficiency tests, etc. should be used to offset the influence of test errors on test results and improve the quality of laboratory work.