Static applications

When diene rubbers are exposed to ozone under stressed conditions cracks develop which are perpendicular to the direction of stress. Whilst ozone must react with unstressed rubber no cracking occurs in such circumstances nor when such rubber is subsequently stressed after removal of the ozone environment. For many years such rubbers were protected by waxes which bloomed on to the surface of the rubber to form an impermeable film. This was satisfactory for static applications but where the rubber was operating under dynamic conditions the wax layer became broken and hence less effective. 

The use of a cut-off distance reduces the fonnal scaling in the large system limit from atom - atoni since the non-bonded contributions now only are evaluated within the locSl sphere determined by the cut-off radius. However, a cut-off distance of 10 A is so large that the large system limit is not achieved in practical calculations. The actual scaling is thus more like where n is perhaps 1.5-1.8. In static applications,... 

Examples A, O-rings for rotary and static applications (43) B, extruded items such as hose, tube, and solid splicable stock C, fuel hose for low temperature service (—57°C) and coated fabric for collapsible fuel storage tanks (40, 45) D, biomedical applications such as soft denture liners (48) and blood compatible parts E, lip seals (42) F, shock absorption and vibration damping mounts, (Photograph courtesy of the Firestone Tire... 

Ready substitution for conventional ftiels in many static applications such as boilers, engines, turbines,... 

The maximum energy product is not, however, the only criterion that can be used to specify the quality of a permanent magnet material whose usefulness is mainly limited to static applications. Of importance in many applications is the magnitude... 

To produce conduction by the first method in an otherwise non-conducting polymer, the required concentration of metallic particles is likely to be greater than about 20% by volume, or 70% by weight. This high particle concentration is necessary in order to achieve continuity of conducting material from one side of the polymer sample to the other. Such high concentrations tend to destroy some of the desirable mechanical properties of the polymer, but composites of this kind are used in conducting paints and in anti-static applications. Conductivities of order 6 x 10 m ... 

Calcium carbonate is used as a low-cost filler in rubber products for static applications such as carpet underlay. Titanium dioxide finds extensive use in white products such as white tire sidewalls where appearance is important. 

Yarns are available in a variety of deniers and merge types that vary in the balance of tensile properties. Special finishes can be applied to increase lubricity, improve fatigue in wet applications, or provide better UV resistance. Ropes using Kevlar or Twaron are particularly useful for static applications or where maximum modulus is required. Technora-based ropes are suited for dynamic applications where resistance to fatigue is important. 

This method consists of two, conceptually different parts. In the first part, the azimuth of each machine axis is determined relative to its own reference line (established by a laser beam) via offset measurements. According to our classifications, this part is relative, contact, manual and static in nature. In the second part, the azimuth of the different reference lines is computed using the IMU attitude measurements (Fig. 7), relative to each other or in absolute sense (geodetic azimuth). This part is relative or absolute, non-contact, semi-automatic (operator aid ) and dynamic. The comparison clearly shows that the first part restricts the method for relative or absolute, contact, manual and static applications. 

PTFE, 15% graphite filled Bearings, wear pads, piston rings - - Anti-static applications... 

The Tg of the PTFPMS ranges from -75 to -65 °C and, unlike PDMS, it does not exhibit low-temperature crystallization at -40 °C. This is because of the inability of the polymeric chain to pack into a crystalline lattice [3]. It can be cross-linkable from various classical processes of the chemistry of silicones such as in the presence of peroxides or from the SiH/Si-CH=CH2 systems [12]. However, the relatively low strength limits the use of fluorosilicones to static applications such as seals for fuel lines [3]. 

The situation as regards mobile applications (Table 5) is, with the exception of power supplies for spacecraft, more problematical than static applications. The potential attractions of the fuel cell electric vehicle compared to the conventional internal combustion engined vehicle include ... 

This pyroelectric effect can be utilized for sensors such as e.g. infrared cameras. However, in sensors that use the electromechanical effect p3To-electricity can be disturbing. The disturbing effects arise especially in low-frequency or quasi-static applications as the temperature drift is often a slow process. A one ohm resistance is applied in parallel to suppress this effect. That way, the pyroelectric induced charges are deflected and the cut-off frequency of the sensor is raised. 

Valves and compressors were amongst the earliest applications areas for PAEK. In static applications the temperature and chemical resistance, coupled with excellent mechanical performance make PAEK suitable for a wide range of metal replacement applications such as housings, linings, thrust washers and seals. However, there are also many moving parts which benefit from excellent dynamic fatigue resistance and wear resistance, with or without lubrication, together with dimensional stability and low-cost fabrication. 

For static applications, the groove should be designed to allow the O ring to be in contact on all its four sides when in position (Figure 2.3). 

A major modem use of electrically conducting textiles is in anti-static applications. Static electricity can not only be uncomfortable, but can also lead to fires and explosions (Kassebaum and Kocken, 1997). Anti-static properties can be conferred by coating fibres with metallized films, intrinsically conductive polymers, polyelectrolytes or by low molecular weight anti-statics in solution (Pionteck and Wypych, 2007). In the food industry, some solutions such as metal or metallized fibres are avoided because of the potential for contamination. Many of the technologies used for anti-statics have been employed for use in electronic textiles. 

Vulkanox 4010 NA/LG antiozoneuit excels in antiflexcracking properties and is used in tires and mechanical goods subjected to dyneunic stress, e.g. conveyor belts, hoses, spring components and elastic couplings. In static applications and in cables and seals, its main function is resistance to ozone cracking, which can be further improved by the simultaneous use of an ozone protective wax. Use should be restricted to dark colored rubber articles where staining and discoloration are of no concern. 

Photo-oxidation proceeds relatively slowly. That is why elastomers made from chlo-roprene rubber exhibit considerably better resistance to ozone attack and weather influences than those made from NR, SBR, and NBR. Moreover, chloroprene rubbers respond well to anti-aging and antiozonant agents so that they can be recommended for use under difficult climatic conditions, e.g., in the tropics. By extrapolating mechanical property changes after several years of weathering in ozone-rich atmosphere, the current technology allows the prediction that chloroprene rubber products will exhibit sufficient strain for most static applications even after 50 years in service [697]. 

Our results are qualitative in that we report positive reactions by audible detection, evidence of burning, or by a visible flash at impact. Our LOX sealant specification (for static applications) requires no positive reactions in 20 tests when tested at the 20 ft-lb level. Materials proposed for use in critical dynamic applications must not detonate during 20 trials at 70 ft-lb. Materials falling in between these levels are selected on the basis of the hazardous potential expected for their intended uses and are evaluated thoroughly under simulated service conditions. 

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