【 Weak current College 】 stage machinery safety design (3)

5. the necessary spare system or device
Equipment incidental result of a fault, to have the necessary measures to continue the use of (or in reducing technical parameters continue to use) equipment, or can make the device returns to a secure location. These measures include: auxiliary transmission system (electric or manual), multipoint transmission system, the computer control system and its components in a redundant configuration. The device comes with secondary transmission system commonly used in music pool lifts, main lifts, and multiple identical equipment auxiliary transmission systems, such as the boom winch room for boom winch of secondary transmission system, often is independent. Multipoint transmission system for alternate in the turntable, auxiliary lift and self-propelled vehicle platform more applications. In the computer control system, a number of important, more components such as the frequency use redundant configuration.
6. the provisions relating to the design data and
Due to the particularities of the stage machinery, foreign standards often design data for specific or different from the provisions of the General machinery. Although there is no specific internal design standards, but in recent years an increasing number of international exchanges, these provisions have also been domestic recognition stage machinery design units. These requirements are:
1) load: static load drawer unit with fixed table of static load is the same as for large and medium-sized Theatre 5000n/m2, the audience of load moving equipment are:
Lifts: 2500n/m2 (single platen or double-bed power Board)
1500n/m2 (double-layer bed down plate)
Train station: 2500n/m2
Turntable (with car turntable): 2500n/m2
Music pool lifts: 2500n/m2
Various secondary weight lifting table:
Bench equipment loads according to actual needs determine, no specific provisions on major equipment such as boom winch, track point crane, free single point lifters abroad are shaping product for design selection.
2) transmission device
Transmission (including the motor, gearbox, drive shaft coupling, etc) for calculation of bearing capacity should be the actual loading (or load rating) twice, the actual load is run in maximum load.
3) additional stroke
Under normal circumstances, the stage machinery of the total trip should include normal travel (by trip terminates switch control), hyper-journey (from the overtravel switch control) and extra trips. Additional travel means the overtravel switching action, before the stage machinery stop walk distance. Additional travel and machine speed and inertia, in General, the speed is less than 0.1m/s, extra travel 0.07m is sufficient. Speed is less than 0.02m/s hydraulic transmission, hydraulic cylinder with cushioning design, no extra trips. Balancing weight of extra stroke must ensure balanced weight and the supporting structure.
4) positioning and locking
Under device must be able to prevent inadvertent movement of the lifting device any possibility, wire, chain as bearing parts and hydraulic cylinder straight top without hydraulic lock or piston clamping device of the structure, you must set positioning locking device to ensure that the lift into the rest doesn't load after long-term effect and sinking.
5) brake
Each brake should be able to withstand all loads, brake braking force is accessible only by gravity or a spring force generation, with brake can be used for manual installations.
6) balance weight
Do not allow using spring instead of balance weight, balance weight should be installed in the frame and prevent the movement of falling out.
7) rope
Rope steel wire of the minimum nominal strength should be greater than or equal to 1570n/mm2, but if you exceed 1800n/mm2, mm2 calculation 1800n/.