Mehanska analiza merilnika velikosti hidravličnega tlaka

Rugelj, Andraž (author), Šajn, Viktor (mentor), Majdič, Franc (co-mentor)

V diplomskem delu je najprej predstavljen trg tlačnih merilnikov za medsebojno primerjavo z ekonomskega in tehničnega vidika. Prikazana je analiza merilnika velikosti tlaka v hidravličnih sistemih, ki se loči na dve posamezni zaznavali. Prvo zaznavalo je mehansko, in sicer togo vpeta krožna plošča, ki se zaradi obremenitve hidravličnega tlaka deformira. Drugo, električno zaznavalo je sestavljeno iz uporovnih merilnih lističev zalepljenih na površino plošče, kateri zaradi njenih deformacij spreminjajo upornost. Predstavljena je raziskava mehanizma delovanja merilnika tlaka v obliki krožne plošče, porazdelitev deformacij po njeni površini zaradi delovanja tlaka ter raziskava mehanizma delovanja Wheatstonovega merilnega mostiča, ki je zalepljen na površini plošče. Predstavljen je tudi postopek in preračun deformacijskega utrjevanja, preračun obremenitev glave merilnika zaradi obremenitve z momentom ključa in poenostavljen preračun tlačne posode. Za analizo napetostno deformacijskega stanja merilnika je uporabljen teoretični in numerični pristop. Rezultate teoretičnih in numeričnih preračunov smo validirali z meritvami sprememb upornosti členov Wheatstonovega merilnega mostiča.

• Language: Slovenian
• Keywords: tlačni merilniki, krožne plošče, deformacijsko utrjevanje, uporovni merilni lističi, wheatstonov merilni mostič, numerična simulacija
• Work type: Bachelor thesis/paper
• Typology: 2.11 - Undergraduate Thesis
• Organization: FS - Faculty of Mechanical Engineering
• Place of publishing: Ljubljana
• Publisher: [A. Rugelj]
• Year: 2019
• Number of pages: XXVI, 65 str.
• PID: 20.500.12556/RUL-109404
• UDC: 621.22:531.7:519.6(043.2)
• COBISS.SI-ID: 16862235
• Publication date in RUL: 01.09.2019

Secondary language

• Language: English
• Title: Stress-strain analysis of a hydraulic pressure sensor

Abstract

The thesis firstly presents the market of pressure sensors for comparison in economical and technical view. The analysis of a pressure sensor in hydraulic systems, which can be separated in two individual sensing elements is presented. The first sensing element is mechanical, specifically a circular plate with clamped edge, which deforms under hydraulic pressure. The second, electrical sensing element is an assembly of strain gauges, which are glued to the surface of the plate and because of the plate deformations it changes their electrical resistance. The research of the mechanism of functioning of a pressure sensor in the form of a circular plate, distribution of deformations on its surface because of hydraulic pressure and the research of the mechanism of functioning of the Wheatstone bridge is presented. The procedure and calculation of autofrettage, calculation of the sensor head due to the load of the torque of the wrench and a basic control for pressure vessels is introduced. For the stress-strain analysis of a pressure sensor we used theoretical and numerical approach. The results of the theoretical and numerical calculations are validated with the measuring of a change in resistance of strain gauges in the Wheatstone bridge.

• Keywords: pressure sensors, circular plates, autofrettage, strain gauges, wheatstone bridge, numerical simulation