Sliding materials

Material is sliding Material is rolling Material is tumbling... 

The use of separate positive control tissues known to contain the antigen being evaluated must be included for each antigen in a run. It is most cost effective to use large in-house tissues that have been fixed with the regular workday s surgical cases for this type of control. Autopsy tissues may also be used as control material. For cytology, cell culture material, effusions, and fine needle aspiration material can be prepared in the form of cytospins and stored (unfixed, desiccated) at -20°C for 6-12 months for use as controls on similarly processed material. All controls should be fixed and prepared with the same protocol as the patient s slide material. 

Sand boils up to 2 ft in diameter were observed along beach Site involved in a lateral spreading landslide. Slumping and fissuring of ground accompanied by some movement toward lake. Horizontal movement only several feet Three large flow slides occurred on the valley sides of the San Pedro River. Volumes of slide material were 40 X 10 8 X 10 and 3 X10 ydL Sliding distance was as much as 1000 ft... 

Cales B. 2000. Zirconia as a sliding material Histologic, laboratory, and clinical data. Clin Orthop 379 94-112. 

The worst man-induced landslide on record took place in the Vajont Reservoir in northern Italy in 1963 (Semenza. and Ghirotti, 2000). More than 300 x 10 m moved downhill with such momentum that it crossed the 99 m wide gorge and rode 135 m up the opposite side. It filled the reservoir for a distance of 2 km with slide material, which in places reached heights of 175 m and displaced water in the reservoir, thereby generating huge waves that overtopped both abutments to a height of some 100 m above the crest of the dam. 

Were accident victims aware of falling, rolling, or sliding material hazard ... 

Type of Conveyor Material Sliding Material Carried ... 

When the material slides on a conveyor deck or slides on the chain carriCTs in an accnmulation section, use the coefficient of friction for sliding material, shown in Table 10-6. Approximate eoefficients of friction for only a few common materials are shown in Table 10-6. Coefficients of friction for materials not listed may be found in handbooks and catalogs. Note that bnlk materials are not listed. Roller chains are seldom used to convey bulk materials beeause fines ean clog the chain clearances and prevent lubricant from reaching critical areas. 

Employees shall not be permitted to work on the faces of sloped or benched excavations at levels above other employees except when employees at the lower levels are adequately protected from the hazard of falling, rolling, or sliding material or equipment. 

Rg. 2 Reduced coefficients of fiiction for PFPE-lubricated TI-6AI-4V compared with unlubricated Ti-6AI-4V in air environment. Sliding material, WC-Co sliding speed, 1 mm/s (0.04 in s) load, 0.5 kgf. 

Fig. 9 Coefficients of friction versus wear cycles for2.5 jim DLC/0.02 fim SiC interlayer coating on T1-6AI-4V, showing reduction in i with increased load. Sliding material, WC-Co sliding speed, 2 mm/s (0.08 in7s).

Fig. 10 Endurance lifetimes of M0S2 on various substrates, showing longest lifetimes for Si3N4 and 52100 bearing steel. Sliding material, T1-6AI 4V sliding speed, 1.2 m/s (3.9ft/s) applied load, 17 N/ball (1.7 kgf/ball).

Fig. 11 Endurance lifetimes of MoSj-coated Ti-6AI-4V specimens, showing significantly increased lifetimes (at high loads) for MoSj coating on nitrogen-implanted (processed at 400 °C, or 750 °F) Ti-6AI-4V substrate. Sliding material, bearing steel sliding speed, 2 mm/s (0.08 in./s).

Pot bearings are based on the incompressibility of natural rubber when placed in a closed steel pot where natural rubber behaves like a fluid (Fig. 19). Pot bearings are able to transfer high compression forces in a small surface and allow rotations around all axes. They provide horizontal and vertical support while rotations are free. Provision of a sliding material allows horizontal displacements in which case the bearings provide only vertical support. 

Hard coated films are available that resist abrasive wear because of their high hardness and resistance to plastic deformation. Moreover, if a film is chemically stable, it is durable to both adhesive and corrosive wear. In addition to the preceding properties, a lowering of friction with any sliding material and chemical stability at high temperature are important conditions in the selection of a wear-resistant film. Ceramics satisfy these requirements to a certain extent. 

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