Knowledge Center

Turning drives on a manual cleatbender is a close second behind the Pittsburgh air hammers for the least popular task in a duct shop because it requires three awkward handle pulls to complete the profile and it’s a profile that the shop is often making throughout the day every day. The first is to pull top handle and bend over the 3/8” of metal inserted to about 150° to 160°, second is to pull the bottom handle and fold over to release the workpiece, then third, after r...

Just about every commercial HVAC job has Shoetap HETO's coming off of the rectangular duct into round pipe runouts.

In HVAC Ductwork, pressure and velocity are two key standards that engineers consider when designing duct systems. However, building ductwork to a higher pressure class does not necessarily improve its ability to handle vibrations caused by changes in velocity.

Spiral Helix’s Model 3600 Tubeformer has a 18 Gauge Mild Steel capacity and the ability to run 3”-64” diameters. The base machine comes standard in 20 Gauge capacity with the forming heads of 4″-20″ diameter included. Forming heads for diameters other than the ones included are in stock at the factory and installed easily by the producer.

SURELOK II P offers greater clinching versatility and is able to fasten material from as thick as 14 gauge to as thin as 32 gauge.

Spiracoustic is a Johns Manville engineered interior liner for spiral ductwork that is positioned as an alternative to the Double Wall method of Perforated and Unfaced Liner by providing a lighter, easier to install product. Providing the same acoustic (noise reduction) and thermal values as double wall but with a 50% weight reduction, drastically reducing installation costs.

Snaplock Buttonpunch on Rectangular Duct is making a comeback! Even though Snaplock has been a SMACNA standard for the Longitudinal Seam on Low Pressure Duct since 1969, many shops left it behind in favor one method- Pittsburgh-that covers all duct pressure classes, thereby streamlining their operation with one method on the longitudinal seam as well as saving money and floorspace from having to buy another machine. Buttonlock and Pittsburgh are run on separate machines.

Tie Rods can be used to support duct sizes over 48” or smaller duct in high pressure applications. Dyn-O-Locs insert into the ends of the hollow tie rods to provide a means of attaching the conduit to the duct.

On Radius Elbows, most shops will tell you that doing the Throats in Pittsburgh is no big deal because they are usually small; but, on a Radius Cheek moving from Pittsburgh to Snaplock means a huge labor savings.

Currently, Rectangular Duct is connected this way:

1. Use a drift pin to line up the holes
2. Manually insert a Carriage Bolt through one side and a Nut on the other side
3. Tighten with a ratchet

Slip and Drive Duct is the most common type of rectangular ductwork. Even the largest Duct fab shops will tell you that Slip and Drive duct accounts for a greater percentage than the TDC/F and Ductmate flanged duct they produce.

Rolled Carbon Steel Prepunched Angle Iron Rings are used in joining ductwork together. Conklin stocks diameters ranging from 3" to 59", manufactured by Midwest Metal Products. Larger sizes, as well as Galvanized, Aluminum, and Stainless Steel Rings, are also available with very short lead times.