Sheathing material

Then, in the early 1980s the concept of OSB was realized in the constmction and operation of large-size mills. OSB is a panel product made from wood strands and somewhat like plywood in that the strands on the two faces are oriented in the long direction of the panel and the core strands are oriented in the cross-panel direction. The use of orientation yields panels having exceUent directional properties, much like plywood, and thus an exceUent and economical stmctural sheathing material is created. 

Difluoroethanol is prepared by the mercuric oxide cataly2ed hydrolysis of 2-bromo-l,l-difluoroethane with carboxyHc acid esters and alkaH metal hydroxides ia water (27). Its chemical reactions are similar to those of most alcohols. It can be oxidi2ed to difluoroacetic acid [381-73-7] (28) it forms alkoxides with alkaH and alkaline-earth metals (29) with alkoxides of other alcohols it forms mixed ethers such as 2,2-difluoroethyl methyl ether [461-57-4], bp 47°C, or 2,2-difluoroethyl ethyl ether [82907-09-3], bp 66°C (29). 2,2-Difluoroethyl difluoromethyl ether [32778-16-8], made from the alcohol and chlorodifluoromethane ia aqueous base, has been iavestigated as an inhalation anesthetic (30,31) as have several ethers made by addition of the alcohol to various fluoroalkenes (32,33). Methacrylate esters of the alcohol are useful as a sheathing material for polymers ia optical appHcations (34). The alcohol has also been reported to be useful as a working fluid ia heat pumps (35). The alcohol is available ia research quantities for ca 6/g (1992). 

Aluminum-sheathed cables should not be connected to other cables because aluminum has the most negative rest potential of all applicable cable sheathing materials. Every defect in the protective sheath is therefore anodically endangered (see Fig. 2-5). The very high surface ratio SJS leads to rapid destruction of the aluminum sheathing according to Eq. (2-44). Aluminum can also suffer cathodic corrosion (see Fig. 2-11). The cathodic protection of aluminum is therefore a problem. Care must be taken that the protection criterion of Eq. (2-48) with the data in Section 2.4 is fulfilled (see also Table 13-1). Aluminum-sheathed cables are used only in exceptional cases. They should not be laid in stray current areas or in soils with a high concentration of salt. 

Fig. 13-1 Resistance load R of cable sheathing as a function of cable diameter d and sheathing material.

Thermocouples. Their protection. In the various, often hostile, environments suitable sheathing materials must be used to protect the thermocouple wires. 

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 previously mentioned "sheathed explosives" were introduced in GtBritain in 1934, after many sheathing materials were tried and rejected. Finally it was decided to use a sodium bicarbonate (and in some cases NaCl) sheath (Ref 49, pp 30-1)... 

It is frequently required to examine the combined performance of two or more processes in series, e.g. two systems or capacities, each described by a transfer function in the form of equations 7.19 or 7.26. Such multicapacity processes do not necessarily have to consist of more than one physical unit. Examples of the latter are a protected thermocouple junction where the time constant for heat transfer across the sheath material surrounding the junction is significant, or a distillation column in which each tray can be assumed to act as a separate capacity with respect to liquid flow and thermal energy. 

An energy balance over the fluid film surrounding the metal wall (Fig. 7.20), neglecting the heat capacity of the sheath material and the fluid film, gives ... 

Pentecost A. (1985a) Association of cyanobacteria and tufa deposits identity, enumeration and nature of the sheath material revealed by histochemistry. Geomicrobiol. J. 4,285-298. 

There are multiple types of thermocouples that can be used. The most common thermocouples used in combustion applications are type K, type S, and type B. The temperature rating for type S and type B are higher than type K but are significantly more expensive and not quite as accurate. The thermocouple sheathing material and length also needs to be selected to be compatible with a given test. 

The drawing method combined with the rolling process, which is one of the most promising methods to fabricate tape-shaped wire, is shown in Fig. 14 [30]. For the sheath material, a Ag tube that allows oxygen diffusion into the core is generally used. Powders of the oxide superconductor are packed into a Ag tube with 4-6 mm diameter and 0.5-1 mm wall thickness. The diameter of... 

Two important groups of insulating and sheathing materials that also come within the definition of plastic are the thermoplastic and thermoset polymeric compounds. 

The sheathing material need not necessarily be the same as the insulation material. It is usually more economical to use a different material such as PE, PVC, CSP, EVA, for general applications and HOFR or ZH for situations where fire resistance and smoke emission must be considered. 

The specifications of sheathing materials can be found, for example, in BS7655, BS6724 and IEC60502. 

Lead is used as a sheathing material for protecting the cable from chemical attack whilst it is buried directly in hostile ground conditions, e.g. in chemical and refinery plants. 

EC60092-359 Part 359 Sheathing materials for shipboard power and telecommunication... 

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