Leakage calculation of reciprocating high pressure hydraulic seals is based on the sealing pressure distribution profiles, i. A lot of work has been published on the tribology of grease lubrication of rolling bearings. Thin film tribology of pharmaceutical elastomeric seals. Tribology 101 introduction to the basics of tribology. Hydraulic dynamic seals for reciprocating or alternating motion.
Pdf effect of seal profile on tribological characteristics such as leakage, friction, and wear in reciprocating hydraulic seals was predicted as a. Elastohydrodynamic lubrication characteristics of hydraulic reciprocating seals have significant effects on sealing and tribology performances of hydraulic actuators, especially in high parameter. Crc handbook of lubrication theory and practice of. Journal tribology and surface engineering laboratory. Neale be, bsceng, dic, fcgi, whsch, feng, flmeche qutt e r wo rt h einemann butterworthheinemann linacre house, jordan hill, oxford ox2 8dp 225 wildwood avenue, woburn ma 0 180 1204 1 a division of reed educational and professional. About the book the objective of this book is to provide guidelines for engineers helping them to improve machine lifetime performance and reliability. Tribology 108 an analysis of the sealing element hydraulic cylinder tribosystem tudor deaconescu, andrea deaconescu transilvania university of brasov 29 bdul eroilor, email.
Boundary lubrication and lubricants seiichro hironaka school of engineering, tokyo institute of technology 1. Introduction the term tribology has been used for 18 years to refer to the branch of engineering that deals with friction, wear, and lubrication. Tribology is a science that deals with the design, friction, wear, and. Pdf study of effect of seal profile on tribological characteristics. The surface texture of shaft counterface has a great influence on the performance of radial lip sealing system. They also cover typical failures found on brake and clutches and the final pdf page give some more information on wear debris analysis. Current trends concerning hydraulic cylinder sealing systems are. Tribological characterisation of turbocharger turbine. Tribology international open access articles the latest open access articles published in tribology international. Then the seal was moved axially towards the grease to place the grease closely to the sealing contact. The sealing system radial lip seal represent a complex tribological system with high requirements to be fulfilled over a long time. Seal s characteristics usually depend on the base stock.
Most of these are focussed on selection and computation of basic machine elements. Delrio, and koohyun chung, layerbylayer thinning of mos2 via laser irradiation. Fundamentals of engineering tribology with applications tribology is the study of the principles of friction, wear and lubrication of machine elements. It utilizes the fluid sealing and tribology expertise of georgia tech and independent consultants. Fundamentals of sealing and tribology of hydraulic reciprocating seals. Industrial lubrication and tribology available volumes and issues. Dehumidifying devices can be placed in the tower and nacelle room. Pdf thin film tribology of pharmaceutical elastomeric seals. In this work, the tribological behaviour of different sealing elastomers has. Sealing solutions skf offers standard seals and custom engineered seal ing solutions to increase uptime, improve machine reli ability, reduce friction and power losses, and extend lubricant life.
The course has been presented at georgia tech since 1988. Neale consulting engineers ltdthe tribology handbook. Wear and friction performance evaluation of nickel based nanocomposite coatings under refrigerant lubrication open access. Pdf the paper examines some fundamental performance and tribological issues of hydraulic reciprocating seals. A new approach on grease tribology in sealing technology. The gear and generator are cooled by heat exchangers recycling the air used in the aircooling system. Evaluation of sealing systems for nonflammable aircraft hydraulic fluids berner, w. Author links open overlay panel max sommer werner haas. During operation the pumping time can be estimated based on the measured friction torque. The behavior of a face seal is determined by the complex interaction of a number of factors.
Thus reveals the close connection between the tribology and the aircraft engine sealing technology. Carbongraphite mechanical seal faces the detection and. Tribological knowledge helps to improve service life, safety and reliability of interacting machine components. Optimization of the tribological performance of rectangular seals in.
This modification consisted of allowing the steam pressure to act on the backside of the ring, hence providing a higher sealing force. Wear particles detach at the areas where a strong junction between contacting asperities is formed between the surfaces sliding relative to one another. To measure the pumping rate of the rotary shaft lip type seal, grease was applied on the shaft at the back side of the seal, fig. Tribological characterization of polymeric sealing. Advantages are usually attained at the price of disadvantages in the other directions. Tribology is the study of the science and technology of interacting surfaces in relative motion and encompasses the study and application of friction, wear, lubrication and related design aspects. Blisters that develop on carbodgraphite seal faces are irregu larities in surface topography which result in poor sealing per formance changes in rque, higher leak rates and a high incidence of catastrophic failure. Most lubricants are intended cause a minor amount of seal swell to ensure sealing without excessive softening. Evaluation of sealing systems for nonflammable aircraft hydraulic fluids j. Tribology of elastomeric seal materials diva portal. These pages from the tribology handbook cover typical failures seen on gears and geartrains, failures associated with wire ropes and failures typically seen on seals and sealing systems. The engineering research on hydraulic reciprocating seals, which commenced roughly in the 1930s, has achieved a basic understanding of performance issues.
Tribology is a science that deals with friction, lubrication and wear in all contacting pairs. The word tribology comes from the greek word tribo meaning rubbing. To further understand tribology, it is important to understand the. In this study, authors developed a pinondisk type apparatus enclosed in a high pressure vessel and characterized tribological behavior of polymeric sealing materials, such as polytetrafluoroethylene ptfe based composites, in gaseous hydrogen pressurized up to 40 mpa. Tribology is a vast and interdisciplinary subject, ranging from the fundamental physics of surface contact and adhesion to the application of advanced materials and lubricants to solve practical industrial friction and wear problems.
The laboratory area totals 1600 square feet in two test cells at the. Miller, in 1862, introduced a modification to the ramsbottom ring. Proceedings of the 1day seminar focus on reciprocating seals organised by the tribology group of the institution of mechanical engineers, london, england, 25 june 2008. Application of tribology in aircraft engine sealing technology. Mechatronics skf flybywire systems for aircraft and driveby. Read download the tribology handbook pdf pdf download.
Pdf principles and design of mechanical face seals. If the base stock causes excessive s swell, additives can do very little to correct it. Cc composite finger seal experiment was performed on a highspeed seal tester. The purpose of this paper is to investigate the leakage and wear. Lecture notes tribology mechanical engineering mit. The concept and theory of tribology will also be applied in solving the contact and friction problems which limit the performance and the service life of seals. Secondly, the counter surfaces of a dynamic seal operate under the same tribological laws as any sliding couples, though with the requirements of low friction and low wear and a long service life. Seal technology is a very mature field, but seal companies face many of the same. The study focuses on friction, wear mechanisms and lubricants. Effect of seal profile on tribological characteristics such as leakage, friction, and wear in reciprocating hydraulic seals was predicted as a function of number of.
Already in the early works in tribology it was recognized that the amount of wear is proportional to the applied load. An experimental technique for investigating the sealing principles of reciprocating elastomeric seals for use in linear hydraulic actuator assemblies in proceedings of the 2nd world tribology congress, vienna, austria, 2001 available on cdrom. Depending on load parameters, the consequences may range from a reduced lifetime due to elevated ring wear to a. Crankshaft seals and sealing surface wear aa gaskets. Department of education and science, 1966, lubrication tribology education and research, a report on the present position and industrys needs, hmso, london. Tribological problems are often related to systems issues. Blistering of seal faces is a critical problem for the seal indus try. The paper examines some fundamental performance and. Tribology of sealing elastomers braham prakash division of machine elements email. Eighty years of research on hydraulic reciprocating seals. Fundamentals of sealing and tribology of hydraulic. Seals and sealing sealing is the control of fluid interchange between two regions sharing a common boundary. Find materials for this course in the pages linked along the left. Elastohydrodynamic lubrication characteristics of hydraulic reciprocating seals have significant effects on sealing and tribology performances.
Some structural or design issues or tolerance considerations may necessitate a relatively large gap between two surfaces which cannot therefore perform the sealing function autonomously. Pdf fundamentals of sealing and tribology of hydraulic. Michael j neale 1 hwlu4 l second edition the tribology handbook the tribology handbook second edition edited by m. For example if the roughness is constant, an increase of the. This new solution enabled the use of more flexible rings, which conformed better to the.
The topics of discussion, though nominally applied to the seal industry, touched on the challenges faced by every business today and are of interest to the tribology community as a whole. Consequently, the seal is always in the mixed or boundary lubrication regime. As a branch of mechanical engineering and materials science, tribology deals with the design of fluid containment systems like seals and gaskets, and lubrication of surfaces in relative motion. Tribology is defined as the science and technology of interacting surfaces. Briscoe coatings tribology properties, mechanisms, techniques and applications in surface engineering second edition kenneth holmberg vtt technical research centre of finland allan matthews the university of shef. For environmental protection leakage control has great importance. Tribology international open access articles elsevier. Industrial lubrication and tribology emerald insight. Duncan dowson, cbe, frs, freng, ceng, fimeche fcgi emeritusresearch professor school of mechanical engineering the university of leeds u.