Destructive testing

According to laboratory tests, destruction of MTBE is possible however, TBA is formed as a decay product. There is still insufficient experience for an ap-phcation in the field. 

NDE methods have the advantage that they cause no harm to the specimen thus the same part can be nondestructively retested or subsequently tested destructively. However, NDE only reveals the location and severity of flaws. The experimenter must judge the importance of each particular flaw. Some times, the importance of a defect is obvious (harmless, or likely to shorten service lifetime, or likely to cause catastrophic failure) otherwise, experimental stress analysis will quantify the severity of the flaw. The defects that are relevant to the strength of short/long fiber RPs are as follows ... 

A European code of practice for reconstitution of irradiated Charpy specimens (used to monitor the embrittlement behaviour of the RPV) was developed within FP-4 project RESQUE. This should allow to re-use surveillance specimens, which were tested destructively in order to determine the fracture toughness. 

Tests, destructive— Tests involving the destruction of assembhes in order to evaluate the maximum performance of the adhesive bond. 

As success is variable, the production of tetraploid mussels requires ploidy testing, which can be made by flow cytometry. Early-stage batches have to be tested destructively on small samples of larvae. In BLUE SEED project trials, the technique produced tetraploidy in D-larvae in five separate experiments, covering both M. edulis and M. galloprovincialis, with tetraploid percentages between 18% and >60%, based on samples of 50-200 ground larvae. Later, non-destructive tests could be made on juveniles and adults by biopsy under MgCL anaesthesia. It was found that... 

Test destructive/nondestructive Any test performed on a part in an attempt to destroy it often performed to determine how much abuse the part can tolerate without failing. There are also nondestructive tests where a part does not change or is not destroyed. 

A new, non destructive method has been developed for testing high strength bolts which is based on measuring the magnetic stress on the head of a bolt. The forces originating in the body of the bolt can be determined in this way since these forces are proportional to the stress state in the head of the bolt. 

The publication of interstate Standard GOST 30415-96" Steel. Non-destructive inspection of mechanical properties and microstructure of metal products by magnetic method" - is the long-expected event for works laboratories and development engineers of non-destructive test means. 

The basic condition of the Standard application - the availability of stable coupled probabilistic or the multiple probabilistic relations between then controlled quality indexes and magnetic characteristics of steel. All the probabilistic estimates, used in the Standard, are applied at confidence level not less than 0,95. General requirements to the means of control and procedure of its performance are also stipulated. Engineers of standard development endeavoured take into consideration the existed practice of technical control performance and test at the enterprises that is why the preparation of object control for the performance of nondestructive test can be done during the process of ordinary acceptance test. It is suggested that every enterprise is operated in correspondence with direct and non-destructive tests, obtained exactly at it, for detailed process chart and definite product type, however the tests have long since been performed after development of the Standard displayed that process gives way to unification. 

GOST 30415 specifies plans for inspection the products of different types and sets formulae for calculation of inspected numbers while applying magnetic inspection. The procedure of random inspection is predetermined to check the authenticity of the correlated relation usage and regulations are introduced to enter data file of non-destructive and parallel tests. 

Not to overload the Statidard, three supplements are predetermined for it. The Supplement A (compulsory ) with the list of statistics is due to compulsory determination by non-destructive magnetic method of mechanical properties test. This Supplement provided the possibility to set the reasonable compromise between two opposite tendencies -to simplify utmost a body of mathematics or, on the contrary, to complicate it to such extent that it becomes inaccessible. 

It is known that diagram " Stress - Deformation " ( SD) is more vividly specifying the current metalwork condition. However, such diagram can be obtained only by destructive testing. The suggested non-destructive magnetic method in the report for the evaluation of SD condition and for the prediction of residual resource of metalwork, where the measurement of coercive force (CF) is assumed as a basis. 

The suggested method is appropriately implemented at the practice. The cost and working hours of unit measurement of it is less than of any alternative method of destructive test and with respect to the authenticity inspection of Stress-Deformation the given method is inferior only to destructive testing. The method was successfully implemented while evaluation of service life of main pipe-lines sections and pressure vessels as well. Data of method and instrument are used as official data equally with ultrasonic, radiation, magnetic particles methods, adding them by the previously non available information about " fatigue " metalwork structure. 

CEN TC 138 (Non-destructive Testing) WG 7 (Acoustic Emission) Draft for General Principals"... 

F. Cattaneo, C. De Michelis, S. Ghia, G.M.Piana "AEBIL a new acoustic emission system for on-line structural integrity monitoring of critical power plant components" to be presented at the 7th European Conference on Non-Destructive Testing, Copenhagen, 26-29 May 1998. 

As it was determined by the test, the stretch diagram at the uniaxial load carrying ability of the carbon plastic UKN-5000 is almost linear until the destruction point. The samples are breaking brittle, and the relative deformation is small (E < 2%). 

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