Outer sheath

Elame-spread and smoke-density values, and the less often reported fuel-contributed semiquantitive results of the ASTM E84 test and the limited oxygen index (LOI) laboratory test, are more often used to compare fire performance of ceUular plastics. AH building codes requite that ceUular plastics be protected by inner or outer sheathings or be housed in systems aH with a specified minimum total fire resistance. Absolute incombustibHity cannot be attained in practice and often is not requited. The system approach to protecting the more combustible materials affords adequate safety in the buildings by aHowing the occupant sufficient time to evacuate before combustion of the protected ceUular plastic. 

Euel assembhes became much more sophisticated, eventually consisting of concentric tubes made from an outer sheath, three fuel tubes, and an inner lithium-target tube, thus having four coolant channels. Locally developed extmsion techniques were used. 

Dyeing is carried out by the method best suited to the fiber used as the outer sheath, eg, acid or premetallized dyes for nylon-based, reactive or direct dyes for cotton-based. 

TROPODUR outer sheath —I Armour -— Tape wrapping — Filler —... 

When last in type designation, it stands lor PVC outer sheath. Steel douhlc-round wire armour,... 

Cable sheaths may be covered with paper and hessian wrappings impregnated with bituminous compounds or with extruded or taped plastics outer sheaths. At pinholes or discontinuities in protective coatings the sheath will be particularly liable to electrolytic corrosion in stray-current areas, and it is desirable to supplement this form of protection by drainage bonds or direct cathodic protection. 

Fuses may be defined as tube- or cordlike containers filled with deflagrating or de tonating materials. Both the outer sheathing material and the weigh and type of expls contd will depend upon the required usage... 

The features, advantages, and disadvantages of the various types of thermocouples are tabulated in Table 3.178. For most process applications, the TC is manufactured with a protective outer sheath that uses an insulating material to electrically separate the TC from the sheath and provide mechanical and environmental protection. In some cases, the TC junction is placed in direct contact with the tip of the sheath to increase speed of response. Recommended practice is to always use an instrument with full isolation. The minimum span of even the best TC transmitters is limited to about 35°C (60°F). 

This development started with an observation of Pennings and Kiel (1965) that, when dilute solutions of polyethylene were cooled under conditions of continuous stirring, very fine fibres were precipitated on the stirrer. These fibres had a remarkable morphology a fine central core of extended CH2-chains, with an outer sheath of folded chain material. Electron microscopy revealed a beautiful "shish kebab" structure (see Fig. 19.16). Shish kebabs have also been observed in experiments without any stirring. For example, by washing polyethylene powder with xylene (Jamet and Perret, 1973) and by crystallising nylon 4 from a glycerol/water mixture (Sakaoku et al., 1968). 

Terminal number at source and source location Terminal number at destination and destination location Core outer sheath color/number Core size... 

The saturation pressure of water at -11.3X is 234 Pa, as shown in Table 14 -9, and if there is condensation or freezing, the vapor pressure at the insulation-outer sheathing Interface will have to be this value. The vapor pressure at the indoors and the outdoors is... 

Plasmalemma—Outer sheath or membrane of muscle tissue. 

Fig. 7.18 Mini-laparoscopy equipment (1.) trocar sleeve, 0 5.5 mm, with insufflation tap and magnetic-ball valve (2.) trocar, conical tip (i.) mini fibre laparoscope, 0 2 mm, angle of view 0°, working length 270 mm (4.) Veres cannula, 0 2.3 mm, with outer sheath, working length 270 mm. (autoclavable)...

Tussur is coarser than cultivated silk an outer sheath of gum is present, but this cannot be distinguished under the microscope. The brown discoloration, which seems to depend, to some extent, upon the source of food, is not confined to the gum but is distributed throughout the whole of the fibre. The cross-section is irregular, and longitudinal striations can be distinguished together with periodic constrictions. 

The same type of conical leadthrough may be used for swaged thermocouples (Fig. 3.2) the outside sheath of which is either silver soldered to the cone or simply glued with epoxy resin. If the outer sheath is cut and only the centre wire is used, porous MgO or AI2O3 powder insulator will be in contact with the pressurized fluid, and some kind of impervious filler, such as uncured epoxy resin, has to be forced under pressure into the insulator. 

Tin is also used as a coating for copper armour wires or armour braiding where rubber compounds are used in the inner or outer sheathing. 

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