Purpose
Τhe fire safety curtain is a mechanism essentially imposed by the Fire Protection Regulation. The curtain is constructed and installed in such a way that, when closing, it interrupts the passage of hot gases, flames and smoke coming from the fire on stage, and protects the audience from radiation for quite a long time, as postulated by Regulations. The curtain must close automatically. The nominal load of the mechanism is determined by the stage mouth dimensions. Velocities range up to 0,35m/sec.
Τechnical Description
The mechanism is based on the principle of electro-drive hoists. An electric gear box rotates a coil system upon which wire ropes are wound up transferring motion through pulleys to the suspension bar of the accessories. Engineering and electronic security systems prevent the dislocation of wire ropes for any reason, not even in case of an impact accident.
The mechanisms comprise the following components:
1. Engine Block / 2. Head pulleys system / 3.Suspension Pulleys system / 4.Accessories Suspension bar / 5 Wire ropes / 6.Stretching wire ropes system / 7.Loading accessories / 8.Safety limit switches / 9. Automation panels, PLC Software, Inverters etc. / 10. Mechanism complimentary (screws, nuts, conical, spring washers, emergency stops, safety bolts, stretching system etc.).
The control panel with the PLC software is installed at the stage mouth. The mechanism is automatically actuated by the fire detection system of the building. The Programmable Logic Controller (PLC) has two buttons for the ascent and descent of the Curtain, and one security button (mushroom) with a key switch. Velocity is regulated through the control program. When the highest or lowest position is reached, the movement towards that direction stops. When a safety limit switch gets actuated, the mechanism is totally immobilized. Then, brakes are automatically actuated to keep the mechanism to its proper position.
The metal crate is a robust compound two-frame construction. The posterior part is 25cm smaller in dimensions along its entire circumference, while the anterior part is attached with metal rods.
The curtain material is non-combustible fiberglass fabric with vertical seams between its sheets.
The vertical motion guide is essential for the perfect operation of the fire safety curtain.
The barrier at the bottom of the curtain is absolutely necessary.
Τhe alarm system gets actuated with the onset of the mechanism, whether programmed or not.