Ductwork Design

Ductwork Design

Diversified Equipment has teamed with USDuct to provide comprehensive ductwork design, fabrication, and installation services. Additionally, Diversified works with a variety of local contractors, skilled in their disciplines, to install, maintain, and repair your equipment.
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Ducting Design and Installation

Clamp Together Ducting
(Rolled Lip Ducting)
Clamp Together Ducting (CTD) is a ducting system that incorporates a gasketed, over-center clamp to draw together and seal the rolled lip formed on the end of ALL components.

The system is available in galvanized and SS material. Standard gauges range from 18-24 gauge with the rolled lip formed directly onto the pipe- as an integral part of the pipe. The system is also available in gauges up to 10 gauge. In this configuration a separate collar is used on the end of the pipe and fitted to the pipe the same as if it were a fitting.

The system is infinitely adjustable, owing to the use of an adjustable sleeve and the adjustable collar found on each fitting. This feature, combined with the clamping action greatly reduces installation time so as to be 70% faster than standard spiral or flanged duct.

Elbows of multiple styles, branches, cut-offs, reducers, adapters and hoods are all fitted with the adjustable collars to further speed the installation.
Flanged Ducting
Flanged Duct

US Duct provides duct with flanges (angle rings) in black iron, galvanized or SS and with or without holes. The duct to which these flanges are attached it available in sizes 3″ and up, and also in black iron, galvanized or SS. Construction methods range from lock seamed pipe and mechanically lock elbows in lighter gauges to full welded product in heavy gauge (even up to 1/4″)- all depending upon the application.

The following are some facts about the options with regard to how the flanges can be utilized.
Vanstone – This term refers to a technique where by a flange is used to mate 90deg lips turned onto the pipe or duct component. In this method the flange is placed onto the pipe, the lip turned back and the flange left loose. Typically the lip is 1/2″ tall (or wide depending on your perspective) When the flanges are pulled together, the VanStoned lips of the pieces that are being connected, are pressed together to make a secure metal to metal connection. Because the flanges are loose on all pieces, alignment of the centerline of the components is easily accomplished.

Welded – This refers to the fact that the flanges are welded to the duct and the faces of the flanges are the mating surface as opposed to the Vanstone where the duct lips are mating. The flanges can be FULL WELDED meaning that there is a continuous weld or INTERMITTENTLY WELDED meaning that there is a weld an intervals around the duct.

Aligning Components with Welded Flange – Because the flanges are welded to the duct and cannot be ‘rolled' it is important that the flanges be aligned to the center line of the fittings and will therefore all line up. There are two options for this alignment. Centerline to the centerline of the holes (align to one hole) or centerline to the center point between the holes. Either is acceptable and is a matter of choice (OR MORE IMPORTANTLY) to the existing duct where present.

Field fitting Flanged Duct – In the case of Vanstone flanges where the flange is left loose, the pipe is typically cut 1/2″ long and then a lip is hammered back at 90 degrees to the pipe by using the flange as an anvil. This is best accomplished by using deep throat vice-grips to hold the flange squarely on the pipe and far enough back to create the desired lip. In the case of Welded flanges- the pipe is cut to length and then the flange welded in place. (Remember to line up the flange with the centerline.)
Spiral Ducting
US Duct is your COMPLETE ducting source. Spiral is an intricate part of that complete offering.
Each duct type has its advantages.

Flanged duct can be made in heavy gauges and the flanges (especially welded and gasketed flanges) provide a very tight and rigid seal.

Clamp Together is fast, adjustable and easy to install. Even the novice can make a great installation quickly.
Spiral is inexpensive and a great consideration for long runs of ducting. It is a definite consideration where in sizes between 16″ and 36″ where there are long runs with few fittings.

Combining these three different duct types affords the end user to get the best system for the best price.
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