Standard Specifications
Furnish and install rolling service doors as indicated. Doors shall be as manufactured by Mahon Door Corporation.
Curtains are to be formed of galvanized steel, aluminum, or stainless steel interlocking slats designed to withstand a wind load of 20 pounds per square foot. Windlocks shall be furnished where required by opening span or for heavier wind load requirements. Steel slats shall be galvanized per ASTM standards and chemically treated for paint adhesion. Both ends of alternate slats shall be equipped with endlocks.
The bottom of each curtain shall be reinforced with two steel, aluminum, or stainless steel angles of equal weight, or an extruded aluminum bottom bar assembly, standard on all doors up to 16’-0” unless specified otherwise.
Counterbalance assembly shall be furnished with oil-tempered helical torsion springs having a 25% safety factor. Springs shall be fixed to tapered cast anchors mounted on a single steel torsion rod. The torsion rod shall be attached to a spring adjusting wheel, adjustable without removing the hood. The entire spring assembly shall be housed in a steel pipe shaft of proper diameter and thickness so as not to exceed 0.03” of deflection per foot of span.
Bracket plates shall be steel plate with sealed ball bearings to support the counterbalance assembly and door curtain. Brackets shall form end closures and support the hood.
Hoods shall be not less than 24-gauge galvanized steel, aluminum, or stainless steel, contoured to fit end brackets, and reinforced with stiffening beads at the top and bottom edges.
Guides shall be fabricated of steel, aluminum, or stainless steel angles not less than 3/16” thick. Guide depth shall be sufficient to retain the curtain under specified wind load. Where windlocks are required, guides shall include windlock retainers. Guides shall be assembled with 3/8” bolts and secured to jambs at spacings not exceeding 3’-0” on center. Bellmouths and door stops shall be incorporated into guide assemblies as standard.
Operation shall be manual with lift handles, hand chain and gear (maximum 35 pounds of pull), hand crank gear, or motor operator.
Locking shall include provision for padlocks by means of slide bolts on manual doors, chain lock keepers for chain-operated doors, locking discs for crank-operated doors, or self-locking gearing on motor-operated doors, with chain lock for emergency hand chain use.
Finish: Steel surfaces shall receive one shop coat of primer paint except galvanized surfaces, bearings, and similar components. Aluminum finishes shall be mill, anodized, or Duranodic. Stainless steel finish shall be mill.