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This paper aims to establish a numerical model to calculate contact pressure for rectangular vane sealing surface of hydraulic rotary actuator. Numerical model can be applied to solve the steady-state Reynolds equation after the oil film thickness and the contact pressure distribution curve of the vane sealing surface are obtained.

The authors established the numerical model of contact pressure base on the theory of elastic after, the Reynolds equation is solved by the inverse solution.

The relationship between the oil film thickness of vane sealing surface and the contact pressure on different sealing location for hydraulic rotary actuator is obtained. At the same time, the lubrication state on the surface of seal is also found when the hydraulic rotary actuator runs stably.

The study shows that the lubricating state of the vane sealing surface is mixed lubrication, when the rotor of the hydraulic rotary actuator is running stably at a certain speed. Meanwhile, this research will provide a theory basis for later experiment for the hydraulic rotary vane actuator.

The purpose of this publication is to determine the influence of selected factors on the durability and the tightness of ferrofluid seals working in water environments. Ferromagnetic fluid (FF) seals are one of the most common applications of magnetic fluid. New applications can be developed by extending the capabilities of these seals in fluid environments, especially in water.

Tests were performed using ferrofluids with differing physical properties like density, dynamic viscosity and saturation magnetization. Working conditions, such as water pressure and peripheral speed, were taken into account.

A mathematical description which allows the selection of an appropriate ferrofluid and the determination of the operating parameters of an FF seal was developed.

This study concerns the influence of peripheral speed, water pressure and magnetic fluid properties on seal tightness.

FLUID SEALING research at BHRA Fluid Engineering has its roots in the early years following the 1939–45 war. In 1945 the then Ministry of Aircraft Production felt that the equipment designer needed sound, basic information on the way hydraulic jack seals functioned and the factors affecting their performance. D. F. Denny was therefore seconded to Imperial College, London, to undertaken programme of research on reciprocating oil seals, which resulted in the publication of a 120‐page volume: “The sealing mechanism of flexible packings”, recently reprinted to meet a continuing demand.

A rotary shaft lip seal operates with a lubricant film separating the seal from the shaft. In this paper the authors present experimental measurements of under‐lip temperatures which show that there is an optimum shaft surface roughness, and present thermal solutions for various convective heat transfer conditions which illustrate that the shaft conductivity is the predominant factor which affects the under‐lip temperature.

The paper outlines the growth in low friction materials, the various elastomers available and the seal designs which have evolved around the utilisation of these materials.

Phosphating mild steel causes the surface to be etched into a network of microscopic channels 0.0004 to 0.0008 in. deep, the phosphate crystals being located on the intervening high spots. With this type of surface, running‐in is both rapid and safe and low friction conditions are soon established. The phosphate crystals do not act as a solid lubricant in the same sense as graphite or M0S2; initial friction is higher and final friction is much lower. Friction of MoS2, for example decreases with rubbing by a factor of 4, from 0.2 to 0.05, whereas the friction of phosphated steel decreased by a factor of 60, from 0.3 to 0.005. In addition, the final friction of the run‐in phosphated surface depended on temperature and pressure in a manner characteristic of ‘thin film’ fluid lubrication, not ‘boundary’ or ‘solid’ lubrication.

Labyrinth seals have been used extensively in industrial production. Better prediction of the performance of a labyrinth seal requires that these mechanisms be understood. This cannot be achieved except by investigating the flowfield details. Therefore, a total variation diminishing (TVD) finite volume scheme is applied to the Navier‐Stokes equations to obtain gas seal flowfield characteristics of axially staggered configuration in this paper. The calculation results here show the evolution process from unsteady flowfield characterization to steady flow pattern. Also, these new flowfield details may provide referable basis for understanding seal mechanisms.