Tribological adhesion of particles in acoustic field

This paper investigates interaction between two particles in acoustic field. It is shown that additional oscillating movements of particles occur as a result of plain acoustic wave action. This sufficiently increases the probability of collisions between particles. Micro-displacements in the collision zone help to remove various pollutants, oxidation products and adsorbed gas molecules from surfaces of particles. Strong adhesive bonds are formed in the contact area between the particles

Sorting plastic waste in hydrocyclone

The article presents material about sorting plastic waste in hydrocyclone. The tests on sorting plastic waste were carried out. Also, the findings received from the performed experiment on the technology of sorting plastic waste are interpreted applying an experimental model of the equipment used for sorting plastics of different density. Article in Lithuanian. Plastiko atliekų rūšiavimas hidrociklone Santrauka. Straipsnyje pateikti duomenys apie plastiko atliekų rūšiavimą hidrociklone. Atlikti plastiko atliekų rūšiavimo hidrociklone bandymai. Taip pat pateikti rezultatai, gauti eksperimento metu šiai plastiko atliekų rūšiavimo technologijai taikant eksperimentinį įrenginio modelį, skirtą skirtingo tankio plastikui rūšiuoti. Reikšminiai žodžiai: plastikas, atliekos, rūšiavimas, hidrociklonas

Research on the efficiency of side exhausters

The article focuses on the relevant technology of environmental protection which includes an effective collection, disposal and control of aerosol and gases contaminants removed from the evaporating surfaces of electroplating tanks. The task of the paper is to help with finding the new ways of collecting and disposing aerosol pollution and to reduce the quantity of equipment and service costs. The article also discusses pollution formation and sorts and performance of side draft and slot hoods for vapour capture. Besides, the paper deals with the formation of vapour over the tank and the features of benefit that depend on absorber‘s shape. Exhaust velocity and its dependencies are analyzed. Article in Lithuanian. Šoninių siurbtuvų efektyvumo tyrimas Santrauka. Nagrinėjamos aplinkos apsaugos technologijos sprendžiant, kaip efektyviai rinkti, šalinti ir kontroliuoti oro teršalus, kurie susidaro virš galvaninių vonių garuojančių paviršių. Darbo tikslas – ieškoti būdų, kaip gerinti oro taršos surinkimą ir šalinimą bei mažinti jos kiekį ir priežiūros įrangos sąnaudas. Aptariamas taršos formavimasis, garų surinkimo šoninių siurbtuvų rūšys, jų veikimas, taip pat garų išsiskyrimo virš vonių ypatumai ir siurbtuvo efektyvumo priklausomybė nuo formos ir sukurto slėgio. Analizuojami siurbimo greičiai ir jų priklausomybės. Reikšminiai žodžiai: galvaninė vonia, oro tarša, šoninis siurbtuvas

Method of Removal of the Plastic Insulator from Waste Cables by Passing them Between Two Rotating Rolls that Have Different Surface Temperatures

Recycling of cable waste, especially the complete separation of metal and insulating material for reuse has always been a problem. Especially this problem is relevant for small enterprises because present processes to recover insulating material consists of many stages and requires expensive equipment. The processes usually involve multistage grinding of the cables into smaller pieces and separating them into metal and plastic fractions. The problem can be solved by thermal methods based on the differences in coefficient of thermal expansion of the insulating material and conductor. By one of these methods the cable is passed between two rotating rolls, while surface of the one roll is heated below the melting temperature of thermoplastic insulator, surface of next roll stays cold. Thus the thermoplastic insulator of the cable breaks after the total impact of thermal deformation of insulator and metal conductor and softening of material of the insulator. Conductor remains undamaged and can be re-covered by new plastic insulating material layer. The experimental cable processing machine was designed and produced in the Laboratory of machines and technologies of the Vilnius Gediminas technical university, initial tests were performed. Such machine can be used by small cable manufacturing and waste management companies, electric devices repair and manufacturing workshops. Results of experimental research are presented as optimal peripheral speed of the rolls (or cable speed) versus diameter of the copper and aluminum conductor of the cable, when the temperature of the “hot” roll equals 160°C

Research on the efficiency of drinking water aeration systems

A number of modern iron removal systems used in individual houses do not work properly. One of the reasons could be inappropriate work of the aeration system. Therefore, the aim of this research is to analyze three types of jet pumps used in individual houses in Lithuania and compare the amount of sucked oxygen with demand for dissolved oxygen the amount of which is calculated. When summarizing the results of research, it was discovered that the ejector worked unstable when flow was low, and therefore stable operation require additional pressure. Article in Lithuanian. Geriamojo vandens aeravimo sistemų efektyvumo tyrimas Santrauka. Didelė dalis individualaus naudojimo modernių geležies šalinimo įrenginių neužtikrina reikiamų geriamojo vandens valymo rodiklių. Viena iš priežasčių galėtų būti netinkamas aeravimo sistemos darbas, todėl šio tyrimo tikslas – ištirti trijų tipų čiurkšlinių siurblių, naudojamų Lietuvoje individualiuose namuose, darbą ir palyginti siurbiamą deguonies kiekį su reikiamu ištirpinti deguonies kiekiu, apskaičiuotu teoriškai. Per tyrimą nustatyta, kad esant mažiems valomo vandens debitams čiurkšliniai siurbliai dirba nestabiliai – stabiliam darbui reikia papildomo viršslėgio. Reikšminiai žodžiai: geležies šalinimo įrenginiai, aeravimo sistema, čiurkšlinis siurblys, reikiamas deguonies kiekis

Preperation for a clean surface / Švarių paviršių paruošimas

The article reviews techniques for preparing clean surfaces used in the manufacturing process, considers the types of clean surfaces and their role in modern production and provides the classification methods of arranging such surfaces. The paper also discusses the principles of methods for solvent cleaning, aqueous cleaning, ultrasonic cleaning, precision cleaning and mechanical cleaning. The study focuses on the possibility of adjusting a clean surface using a water flow, including cavitation. Santrauka Apžvelgiami švarių paviršių paruošimo metodai, naudojami gamyboje. Aptariami švarūs paviršiai, jų tipai ir svarba šiuolaikinei gamybai. Pateikiama švarių paviršių paruošimo metodų klasifikacija. Aptariami valymo tirpikliais, valymo vandeniu, ultragarsinio valymo, precizinio valymo, mechaninio valymo ir valymo, naudojant sūkurinį pulsuojantį vandens srautą, metodų principai. Raktiniai žodžiai: švarūs paviršiai; valymas tirpikliais; ultragarsinis valymas; valymas vandeniu; precizinis valymas; mechaninis valymas; kavitacij

Research and formation of the whirling vortex of the jet pump

This article explores the formation of spiral vortex and application of liquid aerators. Visually, the new method has been applied for three structures of the stream ejector. The paper shows that under the same traffic flow, the venturi tube with blade cup liquid creates maximum ejected liquid contact surface. It has been noticed that the flared shape of the ejector blade that is close to the form of the spiral vortex, creates improvements in a pulsation flow and thus increases the solubility of oxygen in the liquid. Article in Lithuanian. Čiurkšlinio siurblio pulsuojančio spiralinio sūkurio Santrauka. Straipsnyje tyrinėjamas spiralinio sūkurio formavimas ir taikymas skysčio aeratoriuose. Vizualiniu metodu išbandytos trys naujos srautinių čiurkšlinių siurblių konstrukcijos. Parodyta, kad čiurkšliniu siurbliu su menteliniu skysčio užsukimu, esant tam pačiam darbinio srauto debitui, sukuriamas didžiausias siurbiamo skysčio sąlyčio paviršius. Pastebėta, kad mentelinio čiurkšlinio siurblio fakelo forma artima spiralinio sūkurio formai, kuri sukuria srauto pulsacijas, pagerinančias deguonies tirpumą skystyje. Raktiniai žodžiai: : aeravimas, čiurkšlinis siurblys, spiralinio sūkurio forma, srauto fakelas

Preperation for a Clean Surface

The article reviews techniques for preparing clean surfaces used in the manufacturing process, considers the types of clean surfaces and their role in modern production and provides the classification methods of arranging such surfaces. The paper also discusses the principles of methods for solvent cleaning, aqueous cleaning, ultrasonic cleaning, precision cleaning and mechanical cleaning. The study focuses on the possibility of adjusting a clean surface using a water flow, including cavitation.Article in Lithuania

Experimental research of rotor axis revolution orbit in rotor systems with adaptive and sleeve sliding-friction bearings

The accuracy of revolving orbits of rotor axes in rotor systems with adaptive and sleeve sliding-friction bearings is analyzed in the paper measuring vibration dis-placements by contact less displacement transducers (straight measurement method) and vibration accelerome-ters (nonstraight measurement method). Experimental and theoretical research of rotor systems was performed. On the basis of received measurement results rotational orbits of rotor axes and other data formats necessary for analysis were formed. Reasons influencing the formation of irregu-lar form of rotor axes revolving orbits and dependencies between the research results of adaptive and sleeve sliding-friction bearings and the results received by measurement of the searched system by straight and nonstraight methods were defined. Analysis of the received results is made and con-clusions are presented about the diagnostic of revolution accuracy of rotor axes in rotor systems