Southwark Metal SC12 Spiral Coupling 12 Inches

Product Description

The SOUTHWARK METAL SC12 is a 12-inch spiral coupling designed to join sections of round spiral duct in forced-air HVAC systems. This fitting provides a secure, airtight connection between two duct runs, maintaining airflow integrity across the joint. It is sized for 12-inch round spiral duct and is installed by HVAC sheet metal technicians during new construction, system retrofit, or duct repair work. The coupling slides into each duct end and is secured with sheet metal screws and mastic sealant or foil tape per applicable mechanical codes.

The SC12 is suited for use in residential and light commercial HVAC duct systems where 12-inch round spiral duct is specified. Typical applications include main trunk extensions, branch run transitions, and damaged duct section repairs in forced-air heating and cooling systems. It is a standard fitting in sheet metal fabrication and HVAC distribution work.

Key Features

• 12-inch diameter sizing matches standard round spiral duct dimensions
• Slip-fit design allows fast installation into existing duct runs
• Compatible with sheet metal screw fastening and mastic or foil-tape sealing
• Suitable for forced-air heating and cooling duct systems
• Manufactured by SOUTHWARK METAL, an established duct fitting supplier

Compatibility

Designed as an OEM-style replacement and standard fitting for 12-inch round spiral duct systems in residential and light commercial forced-air HVAC installations.

Installation Notes

Installation is performed by licensed HVAC technicians or qualified sheet metal workers. Power down the air handling unit and close associated dampers before working on the duct system. Secure the coupling with sheet metal screws on each end and seal all joints with UL 181-rated mastic or foil-backed tape per SMACNA guidelines and local mechanical code requirements. Do not leave duct joints unsealed, as air leakage reduces system efficiency and may cause pressure imbalance.