Spring Anchor Plates:
Designed to transmit torque from the stationary end of a torsion spring to the building structure and, at the same time, support the weight of the torsion shaft in a level attitude. The anchor plate is able to withstand the lateral forces exerted by a torsion spring. Usually supplied by the general contractor. Refer to Center Support Bearing
.
Spring Assembly:
Hardware used to make up the door counterbalance assembly.
Spring Fittings:
The sleeves or cones, which are used to affix the torsion springs to the torsion shaft. One piece is a stationary sleeve or spring retainer, and the second piece is an adjusting cone or winding sleeve.
Steel Jambs:
Door framing made from either channel or angle iron.
Stop Molding:
Serves to seal the perimeter of the door against weather and light infiltration. Stop molding is nailed to the jamb, outside the door, and is incorporated as one of the final steps in the installation process. Sometimes called doorstop, it is usually wooden or plastic.
Struts:
L-shaped metal reinforcement members attached horizontally to the inside of the door section to add strength and rigidity. Struts are necessary on wide heavy doors to help prevent sagging and bowing and to provide additional reinforcement to comply with the required wind loading. Also called trusses.
Tongue-and-Groove:
The configuration of the meeting rails that differs from shiplap in having matching channel groove and protrusion on the longitudinal edges of the abutting meeting rails for wind and weather protection.
Top Fixture:
Adjustable brackets that carry track rollers mounted on the top corners of the top section of the door.
Top Header Seal:
Flat weather strip fastened along the full width of top door section as a seal along the header.
Top Rail:
The horizontal rail forming the top horizontal member of a door as distinguished from the meeting rails and bottom rail.
Top Seal:
Weather stripping which fastens to the top of the door to provide a seal along the top of the opening.
Torque:
The turning effect of a tangential force acting at a distance from the axis of rotation or twist; torsion springs apply such effect to spring shafts.
Torsion Shaft:
The shaft of a torsion spring assembly, which transmits lifting force of the torsion springs to cable drums and lifting cables.
Torsion Spring Counterbalance Assembly:
Designed and constructed to provide a safe and durable conversion of spring torque to lifting force by balancing the weight of a sectional overhead type door.
Torsion Springs:
Mounts above the door opening. The springs are manually wound, or charged, then set to a shaft which runs through the spring. The spring turns the shaft, which raises or lowers the door via the cables winding on drums.
Track:
Provide a guide for the roller wheels. The vertical track is mounted to the jambs with brackets on each side of the door opening. The horizontal track contains a curved end called the radius. Refer to Radius
. In the closed position, the door is resting in the vertical track. In the open position, the door is suspended from the horizontal track. Sectional door track usually consists of 4 pieces: 2 vertical pieces and 2 horizontal pieces.
Trajectory:
The arc of travel, or sweep of the top section, as the door is raised from closed to open position, important in planning the location of pipes, light fixtures, etc.
Vertical Lift:
A hardware design that allows a sectional door to open vertically along the wall above the door opening.
Wicket Door:
Hollow-metal pedestrian door installed adjacent to the sheet door sharing the same building opening. (Commercial door application).
Winding Bars:
Used by installers to set initial tension on torsion springs at the winding cones.
Winding Cone:
Part that fits into a torsion spring, permitting winding of the torsion spring and tension adjustment.
Winding Sleeves:
Designed to allow the application in a safe manner of torque from a torsion spring. The design properly retains a torsion spring when fully wound or unwound and withstands the radial and lateral forces exerted by the torsion spring.
Wind load:
The lateral force that the wind exerts upon a door as it stands in a closed position.
Wood Jamb Mounted:
Regular method of mounting vertical track to wood jambs.
Wood Jambs:
Upright piece forming the side of the door opening and is made of wood.