BACKGROUND Stylets are the most frequently used devices for tracheal intubation, but can be a source of postoperative pharyngeal pain or hoarseness. In this study, we evaluated extraction forces between polyvinyl chloride (PVC) and stannum (Sn) stylets with various lubricants. FINDINGS Using a manikin, we compared extraction forces between PVC and Sn stylets under four different conditions: w...

The study was conducted to develop castor oil – graphite lubricants for cold extrusion of aluminium alloy and to investigate the effect of the developed lubricant on the extrusion pressure of aluminium alloy. Cold extrusion process at a constant extrusion ratio of 1.25:1 was used on 14mm diameter by 30mm long aluminium alloy billets. Experimental results showed that onset pressure ranges from 1...

In the present study, a modified Reynolds equation including the electrical double layer (EDL)-induced electroviscous effect of lubricant is established to investigate the effect of the EDL on the hydrodynamic lubrication of a 1D slider bearing. The theoretical model is based on the nonlinear Poisson-Boltzmann equation without the use of the Debye-Hückel approximation. Furthermore, the variatio...

This paper investigates the effect of contact geometry, temperature and displacement amplitude on the fretting behaviour of an aero-turbo oil lubricated cylinder-on-flat contact. To be effective, the lubricant needed both to penetrate the contact and then offer protection. Lubricant penetration into the fretting contact is found to be controlled by two physical parameters, namely (i) the width ...

The revolution in industrialization throughout the world has boosted the utilization of machinery and shifted the muscle power to machines. The use of machines in various sectors has increased the demand of petroleum based lubricants. Lubricants act as an antifriction media, facilitating smoother working, reducing the risks of undesirable frequent failures and maintaining reliable machine opera...

The development of new gearbox designs, the quality requirements as well as the growing ecology consciousness influenced the development of synthetic transmission gear oils with extended replacement interval. Monitoring of lubricant operating properties in the application and the analysis of the gained results provide the lubricant replacement at the right time. In this way the costs of lubrica...

Sliding friction across a thin soft lubricant film typically occurs by stick-slip, the lubricant fully solidifying at stick, yielding and flowing at slip. The static friction force per unit area preceding slip is known from molecular dynamics (MD) simulations to decrease with increasing contact area. That makes the large-size fate of stick-slip unclear and unknown; its possible vanishing is imp...

We investigate the role of defects and disorder in a 2D-model lubricant interposed between two sliding substrates. Specifically, we consider localized defects (vacancies) and extended defects (grain boundaries) in the lubricant confined between two perfect rigid chains. This work verifies in particular when the perfect ”quantized” dynamical sliding regime identified in previous work [1, 2] is p...

current world conditions require compressors to be both efficient and economical to manufacture. one means of improving efficiency in a rotary vane (or any) compressor is to use the lubricant as a heat transfer agent. A rotary vane refrigerator compressor was modified and instrumented for calorimeter testing so that the performance improvement could be identified. The changes and testing were c...

Phosphonium ionic liquids (ILs) have various uses, including as environmentally benign lubricants and lubricant additives. The properties behavior of these ILs depend on their chemical composition, i.e., cation anion combination, the operating conditions. One approach to understanding relationships between conditions, lubricant-relevant is classical molecular dynamics simulation. Although this ...