Opetovana upotreba etalaona za provjeru penetrantskih sustava

master's thesis

• Title (english): Repeated use of reference test blocks for penetrant products
• Author: Sandra Jantol
• Mentor: Damir Markučič (mentor)
• Granter: University of Zagreb; Faculty of Mechanical Engineering and Naval Architecture; Zagreb
• Defense date and country: 2014-07-17, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Mechanical Engineering

Abstract

Problematika opetovane upotrebe radnih etalona za provjeru sustava ispitivanja penetrantima leži u činjenici da nema egzaktno propisanog kriterija do koje mjere je moguće tolerirati umanjene performanse radnih etalona. U praksi se može dogoditi da radni etalon pokazuje lažne indikacije ili ih uopće ne pokazuje, a da toga nismo ni svjesni pa shodno tome mijenjamo PT sustav koji je ispravan ili upotrebljavamo PT sustav koji nije ispravan. Iz navedenih razloga, potrebno je, u kontinuitetu, preporučljivo jednom godišnje, provjeravati ispravnost radnih etalona za provjeru PT sustava kako bi se takve situacije svele na minimum. Norma ISO EN 3542-2 [1] propisuje da bi trebalo barem jednom godišnje radni etalon poslati na provjeru ispravnosti neovisnom laboratoriju, međutim u tom periodu ako se ispravno ne postupa s etalonom, može davati nekvalitetne rezultate i prije tog roka. Iskustveno su dane neke smjernice kako postupati s radnim etalonom, međutim tu postoji mnogo utjecajnih čimbenika pa nema univerzalnog obrasca. Ovim radom se želi ukazati na problematiku i nedorečenost kriterija za opetovanu upotrebu radnih etalona za provjeru PT sustava te istražiti usporedivost rezultata opetovane upotrebe s obzirom na utjecajne čimbenike (vrijeme penetriranja i razvijanja, temperaturu površine etalona, uvjete promatranja indikacija te različite metode čišćenja same površine etalona prije ispitivanja). U eksperimentalnom dijelu su odabrani radni etaloni podvrgnuti različitim uvjetima ispitivanja u različitim rasponima mjernih vrijednosti te se očitavala oštrina i kontrast indikacija i fotografski su se bilježile. Dobiveni rezultati su uspoređeni da bi se došlo do zaključaka kako mjerodavno i opetovano upotrebljavati radne etalone, a da nam pružaju vjerodostojne informacije s obzirom na utjecaj ispitivanih čimbenike. Navedena ispitivanja su provedena u skladu s obitelji norma EN ISO 3452 [1] [2] [3] [4] [5].

Abstract (english)

Problems of repeated use of reference blocks for verification of penetrant testing lies in the fact that there is no exact criteria prescribed to which level it is possible to tolerate a reduced work performance of reference blocks. In practice it may happen that the reference blocks shows false indications or does not show, and that we are not even aware of, and resultant change the PT system which is correct or use the PT system that is not correct. For these reasons, it is necessary, in continuity, it is recommended once a year, check the accuracy of reference blocks for checking the PT system to reduce to a minimum such situations. Norme EN ISO 3542-2 [1] provides that should at least once a year, send a reference blocks to check accuracy by an independent laboratory, however during this period if not properly treated with established standards, may give poor quality results and prior to that deadline. Experiential give some guidance how to deal with the reference blocks, however there are a number of factors and there is no universal rules. This work will discuss the problems and the vagueness of the criteria for repeated use of reference blocks for checking the PT system and investigate the comparability of the results of the repeated use due to the influence factors (time of penetration and development, surface temperature of reference block, indications observing conditins and different methods of cleaning the surface of blocks before testing). In the experimental part there are selected reference blocks subjected to various test conditions in different ranges of measurement values and were read the sharpness and contrast of indications and photographic were recorded. The results are compared in order to come to the conclusion how relevant and repeated use of reference blocks, and to provide us with credible information with regard to the impact of the studied factors. The above tests were conducted in accordance with the family of norms EN ISO 3452 [1] [2] [3] [4] [5].

• Keywords: penetrantski sustav; radni etaloni; opetovana upotreba etalona; utjecajni čimbenici
• Keywords (english): penetrant system; reference blocks; the repeated use of blocks; influential factors
• Language: english
• URN:NBN: urn:nbn:hr:235:749910
• Study programme: Title: Mechanical Engineering; Study programme type: university; Study level: graduate; Academic / professional title: magistar/magistra inženjer/inženjerka strojarstva (magistar/magistra inženjer/inženjerka strojarstva)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2019-05-22 11:20:22