Precision Industrial Services supplies 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 flanges can either be vanstoned or welded in place. Vanstone – This term refers to a technique where by a flange is used to mate 900 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 center-line 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.
Straight Duct: The duct is a nominal 5 feet in length. The standard gauge duct is first formed by cutting stock sheet metal to specific widths. After rolling, the rolled duct is laser welded to a completely sealed seam. The flanges are added to the duct and the edges are vanstoned to hold the flanges in place. Duct Standard Gauges for the duct are 26 ga for 3”, 24 ga for 4-6”, 22 ga for 7-12”, 20 ga for sizes 13-22”, and 18 ga for 24″ and up. Typically, all sizes can go 2 gauges heavier and still have the vanstone lip formed onto the end. But the duct is also available in gauges up to and including 10 gauge. At the higher gauges and dependent upon the size, the flanges will be welded to the duct.
Elbows: Elbows are available in a variety of styles depending upon the diameter, radius (length of turn), and gauge and material required. These include welded halves with a longitudinally welded seam, formed tube elbows, and gore/segmented elbow which are mechanically locked or fully welded to form the elbow. Typical degrees are 90, 60, 45 and 30 degree with standard radii of 1, 1.5 and 2.5 x Diameter. BUT ALL DEGREES AND ALL RADII ARE AVAILABLE. Elbows are typically two gauge heavier than the duct.
Branches: (Lateral, T on tapers, Y’s, double Branches, etc.): These are built to specification with the lightest gauge being 18 gauge. The laterals are FULLY welded to the body for a smooth transition. Standard degrees are 30, 45 or 90.
Cut-offs and Blast Gates: Standard cut-offs consist of aluminum body gates with either galvanized or SS blades. Other options include
- Fabricated galvanized or SS bodies
- Fully welded air tight galvanized or SS bodies
- Fabricated bodies with air tight UHMW seals that press against the blade
- Automatic gates- pneumatically operated/electrically activated- in any of the above styles. Cylinders require a minimum of 90 psi. Activating voltages can be 12 or 24V AC or DC and line voltage up to 240V.
Miscellaneous Fittings: Adapters, hoods, transitions, reducers et al. are available to specification. Gauge is dependent upon size and application but range from 22 to 10 ga.