Safe length

Inclining the hearth increases the safe length. This is the principal reason why furnaces for heating thin stock have inclined hearths. Hearth inclination reduces pusher force in accordance with the equation... 

Inclined hearth furnaces tend to create more natural draft, pulling in cold air at the low end of the incline. Excessive hearth inclination interferes with pressure conditions in the furnace. (See chap. 7.) An inclination of more than 8 degrees is rare. The safe length of hearth also depends upon the shape of the contacting surfaces of the billets. If the billets or slabs have round edges, climbing occurs easily. Crooked billets also tend to climb. 

The use of fatigue data and crack length measurements to predict the remaining service life of a stmcture under cyclic loading is possibly the most common application of fracture mechanics for performance prediction. In complex stmctures the growth of cracks is routinely monitored at intervals, and from data about crack growth rates and the applied loadings at that point in the stmcture, a decision is made about whether the stmcmre can continue to operate safely until the next scheduled inspection. 

AC 94377. The compound l-(3-chlorophthalimide) cyclohexanecarboxamide [51971 -67-6] (Table 3) (45), also known as AC 94377, is a phthalamide that has plant growth regulating properties. It is relatively nontoxic so that its use in floricultural crops appears to be safe. It is mainly used to control stem length and stem numbers in hybrid tea roses (23). However, it has very limited use and is stiH experimental. 

Safe condition at the time of delivery by the seller will, however, include proper packaging, necessary sterilization, and other precautions required to permit the product to remain safe for a normal length of time... 

Liquid sterilants are known to corrode the metal parts of articles and instmments that are to be sterilized, although articles composed exclusively of glass or certain type of corrosion-resistant metal alloys can be safely processed. Because the degree of corrosion is related to length of exposure, many articles are merely disinfected in a shorter exposure time. Disinfection may be suitable for certain appHcations. The safety of using Hquid sterilants must be judged by a qualified microbiologist. 

In case of static drives also generating simihir switching surges, their manufacturers provide the safe cable lengths as a standard practice. Section 6.14.1. 

The tests may be conducted on a few ratings with different sizes and lengths of cables to simulate the near actual condition of the installation. One should be more conservative than liberal on cable lengths to obtain safe... 

In the first case, if we had considered a safe line length of 250 km, this would become 500 km for a symmetrical line. Figure 24.18 illustrates such a condition. Depending upon the length and type of line, a line length compensation may be required. Most transmission lines are seen to be within permissible lengths and only a few may require such a compensation. Nevertheless, it may be worth reducing the phase displacement between E, and to less than 15° electrical, to further iinprove the quality and stability level of power transmission. 

First, the pressure vessel must be safe from plastic collapse that is, the stresses must everywhere be below general yield. Second, it must not fail by fast fracture if the largest cracks it could contain have length 2a (Fig. 16.4), then the stress intensity K CTV must everywhere be less than K. Finally, it must not fail by fatigue the slow growth of a crack to the critical size at which it runs. 

This is sufficient for the engine to run for 8 hours on each of 832 open days for demonstration purposes, i.e. to give 8 hours of demonstration each weekend for 16 years. A crack of 3 cm length is still far too small to go critical, and thus the engine will be perfectly safe after the 5.9 X 10 cycles. Under demonstration the power delivered will be far less than the full 105 horsepower, and because of the Ac dependence of N, the number of cycles required to make the crack grow to 3 cm might be as much as 30 times the one we have calculated. 

Figure 7-68. Maximum allowable length of a vessel vented at one end, or maximum distance between vents as a function of the vent diameter for the safe venting of deflagrations of dusts and gases. By permission, American Institute of Chemical Engineers, Meeting Mar. 6, 1988 by I. Swift (deceased) [56], with data from Ref. [54].

In 1976 the Swedish government stipulated that no new nuclear reactors should be charged until it had been shown how the radioactive waste products could be taken care of in an "absolutely safe manner" (8). Consequently, the nuclear power industry (through their joint Nuclear Fuel Supply Co, SKBF) embarked on a program referred to as the Nuclear Fuel Safety (KBS) Project (8). In one of the schemes (9) a repository for spent nuclear fuel elements in envisaged at a depth of 500 m in granitic bedrock. The repository will ultimately contain 6000 tonnes of uranium and 45 tonnes of plutonium. The spent fuel elements will be stored in copper cylinders (0.8 m in diameter and 4.7 m in length) with a wall thickness of 200 mm the void will be filled with lead. 

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