spiral-ductwork-manufacturingMKT products are factory fabricated to meet or exceed 3rd edition 2005 SMACNA Standards. MKT standardizes most spiral duct with USA mill-stamped, G60 galvanized steel*. We not only meet requirements set by the state and federal entities, but our highest standards are held by our own quality control guidelines. 
*Specific needs and application do apply

Customers are able to purchase spiral accessories from MKT as well. In addition to the 10′ lengths, MKT inventories elbows, air-tites, high efficiency take offs, bell-mouths, duct connecting systems and duct hanging systems.

Customers get the same attention to service they have come to rely on. From the initial take-off/estimate to the final delivery.

Materials used in the production of spiral duct:

  • Galvanized
  • Galvaneal or “paint grip”
  • Aluminum
  • Stainless Steel
  • PCD coated
  • Agion® Antimicrobial

Diameters produced: 4″ to 100″ capabilities

spiral-ductLengths produced:
MKT produces and inventories 10-foot lengths of all diameter duct. Specific lengths, longer or shorter than 10 foot are available, up to 20-foot maximum.

Gauges: 18 to 26

Coatings: Coatings for industrial or aesthetic applications are available
PCD pre-coated galvanized spiral duct
Powder coated for a multitude of colors is available on request

Double wall insulated duct:

  • Perforated inner wall for insulation and decibel applications
  • Solid inner wall for insulation only



  • MKT recommends using slip in couplings up to 24″ diameters
  • Quick, simple, relatively inexpensive
  • Light to moderate strength characteristics
  • Requires sealing in the field if necessary



  • Simple installation process
  • Can be installed on-site
  • Shop installation has proven to:
  • protect the ends of spiral in transit
  • reduce labor time in the field
  • Available in 8″ to 72″ in standard 2″ increments
  • Requires sealing in the field or the shop if necessary

Barrel Clamp


  • Self Sealing
  • Time and labor saving
  • Adjusts automatically to slight duct diameter variations
  • Offers inner ring for use with Spiralmate on Double Wall spiral connections
  • Has been lab tested to 18″ positive WG and 10″ negative WG

Angle Rings


  • Typically used in heavy, industrial applications
  • Larger diameter and gauge spiral/round duct uses angle rings
  • Can be used in conjunction with “van stoning” on the round duct for a “slip ring” capability
  • Requires additional gasketing if required
  • Available in all materials including galvanized, pricing and availability on request