RESEARCH OF THE INFLUENCE OF CONSTRUCTIVE ELEMENTS OF FLOW PART OF THE IRRIGATOR OF FIREFIGHTING SYSTEM ON IT`S CONSUMPTION CHARACTERISTICS

Abstract

Abstract. Problematic issues, which periodically  arise  while technical characteristics testing according to methods and procedure which specified in DSTU EN 12259-1:2019, for individual batches of specimens  of irrigators of water-foam extinguishing system with or without marking of well-known foreign brands, but unknown manufactures, probably not original product, due to which, objectively, these speciments of sprinklers are rejects, have been analyzed. In particular, it is connected with obtaining unsatisfactory test results regarding such product quality indicators as: K – factor. To find out the reasons for these unsatisfactory test results, theoretical research was conducted in the field of technical fluid mechanics (hydrodynamics) and the cause of the mentioned problem was previously identified. Further research of sprinkler specimens, that did not meet the requirements of the specified standard, confirmed the influence of the identified design flaw, presumably allowed during the manufacture of the rejected sprinklers, on the test results. It was clarified and confirmed that the reason lies in the manufacturing defect of the flow part of the sprinkler, namely the presence of a sharp edge on its inlet opening. After finalizing the design, by removing the sharp edge (chamfering), the results of repeated hydraulic tests showed that the parameters of the sprinkler returned to normal. The results of this research are presented in the materials of this publication in graphic form.  Therefore, it's necessary in any possible way, including this publication, inform manufacturers and customers of this production about necessary checking of presenting of chamfer or smooth rounding of the edge of inlet opening of the flow part of the product, becouse it's absence can be one of signs of the non-original sprinklers and reason of irrigators defect.