Srednji čas do okvare hidravličnega zavornega ventila

Novak, Nejc (author), Majdič, Franc (mentor)

V današnjem času se daje velik poudarek varnosti in zanesljivosti naprav. Eden izmed novejših standardov glede varnosti strojev in naprav je SIST EN ISO 13849-1. Pomembnejša tema v omenjenem standardu je določitev srednjega časa do okvare sestavine oziroma celotne naprave. Cilj naloge je določitev srednjega časa do okvare (MTTF) hidravličnega zavornega ventila. Ta je namenjen zaviranju delovnih strojev in je zato ključni člen zavornega sistema. Ker je ventil hkrati tudi varnostni del krmilnega sistema, je pri njegovi morebitni okvari ogrožena varnost ljudi, zato je treba analitično in eksperimentalno dokazati uporabno dobo zavornega ventila. Izvedli smo trajnostni test petih zavornih ventilov. Po 1000-ih urah testiranja smo test ustavili in izračunali srednji čas do okvare ventila. Noben od ventilov se med testiranjem ni okvaril.

• Language: Slovenian
• Keywords: hidravlični zavorni ventili, srednji čas do okvare, stopalke, izhodni delovni tlak, izgube varnostnih funkcij, delovni cikli, varnost naprav, okvare, zanesljivost
• Work type: Master's thesis/paper
• Typology: 2.09 - Master's Thesis
• Organization: FS - Faculty of Mechanical Engineering
• Place of publishing: Ljubljana
• Publisher: [N. Novak]
• Year: 2019
• Number of pages: XXI, 66 str.
• PID: 20.500.12556/RUL-109360
• UDC: 621.646.2:62-592.2(043.2)
• COBISS.SI-ID: 16842011
• Publication date in RUL: 31.08.2019

Secondary language

• Language: English
• Title: Mean time to failure of hydraulic brake valve

Abstract

Nowadays, great emphasis is put on safety and reliability for machines and devices. One of the newer standards for safety of machines and devices is SIST EN ISO 13849-1. A more important topic in this standard is the determination of the mean time to failure of a component or an entire device. The objective for the task is to determine mean time to failure (MTTF) of the hydraulic brake valve. Valve is a key element in a braking system for heavy-duty machines. Since a valve is also a safety part of the control system, its potential failure will result in a hazardous situation for people. Therefore it is necessary to prove analytically and experimentally the useful time of the brake valve. A sustainable test was carried out. After 1000 hours of testing, the test was stopped and the mean time to failure of the valve was calculated. None of the valves failed during testing.

• Keywords: hydraulic brake valves, mean time to failure, pedals, outlet working pressure, loss of safety functions, working cycles, safety of machines, failures, reliability