Theatre Design & Technology - Summer 1986 - 6
SINGLE FAIL
THEATRE
by Olaf Soot
Machinery must obey the laws of
physics and mechanics whether installed in a theatre or in an industrial
plant. Design principles developed for
industrial machinery can be successfully applied to the theatre by engineers
well versed in these principles and in
theatre operations.
Industrial machinery is covered by
codes and safety standards and is subject to periodic official inspections.
Unfortunately, special machinery for
theatres or for movable building components is not so standardized and it is
only seldom engineered or analyzed.
Too often the machinery involved does
not comply with good design practices
and can be sometimes actually selfdestructive. Motors have been oversized while hoist anchors, cable connectors, linkages, and other components
have not been strong enough to withstand the maximum overload torques
these motors can develop. As a result,
motors have torn apart hoist components, and lives have been lost because
there was no secondary built-in safeguards to prevent the dropping of the
load.
Conservati ve design red uces the
probability of failure but does not nec4
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FIGURE 1
essarily protect against lack of quality,
lack of inspection, or lack of proper
maintenance. Furthermore, for practical purposes, a contractor cannot supply conservative equipment when bidding on a job, based solely on performance specifications and low price.
Therefore, where safety comes into
play, single- failure-proof design should
be used for critical systems and components. This means that the system
must be designed and built so that a
malfunction of anyone structural me-
Theatre Design & Technology / USITT / Summer 1986
chanical or electrical component due to
misuse, hidden defect, or longtime wear
would not create a damaging condition
but would rather stop the operation of
the system and give notice that the fault
has to be corrected.
A passenger elevator, for example,
is a single-failure-proof device. The
elevator does not fall if a hoisting cable
breaks. In fact, elevators are designed
not to fall even if all the hoisting cables
break because the independent braking
system would engage the guide rails and
Table of Contents for the Digital Edition of Theatre Design & Technology - Summer 1986
Contents
Theatre Design & Technology - Summer 1986 - 1
Theatre Design & Technology - Summer 1986 - 2
Theatre Design & Technology - Summer 1986 - 3
Theatre Design & Technology - Summer 1986 - Contents
Theatre Design & Technology - Summer 1986 - 5
Theatre Design & Technology - Summer 1986 - 6
Theatre Design & Technology - Summer 1986 - 7
Theatre Design & Technology - Summer 1986 - 8
Theatre Design & Technology - Summer 1986 - 9
Theatre Design & Technology - Summer 1986 - 10
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Theatre Design & Technology - Summer 1986 - 12
Theatre Design & Technology - Summer 1986 - 13
Theatre Design & Technology - Summer 1986 - 14
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Theatre Design & Technology - Summer 1986 - 16
Theatre Design & Technology - Summer 1986 - 17
Theatre Design & Technology - Summer 1986 - 18
Theatre Design & Technology - Summer 1986 - 19
Theatre Design & Technology - Summer 1986 - 20
Theatre Design & Technology - Summer 1986 - 21
Theatre Design & Technology - Summer 1986 - 22
Theatre Design & Technology - Summer 1986 - 23
Theatre Design & Technology - Summer 1986 - 24
Theatre Design & Technology - Summer 1986 - 25
Theatre Design & Technology - Summer 1986 - 26
Theatre Design & Technology - Summer 1986 - 27
Theatre Design & Technology - Summer 1986 - 28
Theatre Design & Technology - Summer 1986 - 29
Theatre Design & Technology - Summer 1986 - 30
Theatre Design & Technology - Summer 1986 - 31
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Theatre Design & Technology - Summer 1986 - 33
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Theatre Design & Technology - Summer 1986 - 36
Theatre Design & Technology - Summer 1986 - 37
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https://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1966May
https://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1966Feb
https://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1965Dec
https://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1965Oct
https://www.nxtbook.com/nxtbooks/hickmanbrady/tdt_1965May
https://www.nxtbookmedia.com