Strut channel
Strut channel, often referred to colliqually by one of several manufacturer trade names (e.g. "Kindorf", "Unistrut", "SuperStrut", "Strut", "Metstrut"), is a standardized formed steel (or sometimes aluminum) structural system used in the construction and electrical industries for light structural support, often for supporting wiring, plumbing, or mechanical components such as air conditioning or ventilation systems. Strut is formed from metal sheet, folded over into an open channel shape with inwards-curving lips to provide additional stiffness and as a location to mount interconnecting components. Strut usually has holes of some sort in the base, to facilitate interconnection or fastening strut to underlying building structures.
The main advantage of strut channel in construction is that there are many options available for rapidly and easily connecting lengths together and other items to the strut channel, using various specialized strut-specific fasteners and bolts. It can be assembled very rapidly with minimal tools and only moderately trained labor, which reduces costs significantly in many applications. A strut channel installation also can often be modified or added-to relatively easily if needed. The only alternative to strut channel for most applications is custom fabrication using steel bar stock and other commodity components, requiring welding and/or extensive drilling and bolting, which has none of the above advantages.
In US units, the basic typical strut channel forms a box 1 5/8 inch by 1 5/8 inch. In metric units, this is a 41 mm by 41 mm unit. There are several additional sizes and combined shapes manufactured. [1]
Strut channel is available from numerous vendors and commonly found in electrical, plumbing, and structural supply warehouses and catalogs.[1] [2] [3] [4]
Shapes
Basic strut channel comes in the open box section, 1 5/8 by 1 5/8 inch square cross section. A half height (1 5/8 inch wide, 13/16 inch tall) cross section version is also available, used mostly where mounted directly to a wall as it has significantly less stiffness and ability to carry loads across an open space or brace. A deep channel 2 7/16 inches tall and 1 5/8 inch wide is also manufactured.[1]
The material used to form the channel is typically 12 gauge (0.1046 inch) or 14 gauge (0.0747 inch) thick sheet metal.
Several variations are available with different hole patterns for mounting to walls and supports. Solid channel has no holes predrilled, and must either be drilled on site or mounted in another fashion. Punched channel has round holes, large enough for 5/8 inch threaded steel rod or bolts, punched in the top of the channel at regular 1 7/8 inch centers. Half-slot channel has short, rounded end rectangular slots punched out on 2 inch centers. Slot channel has longer slots on 4 inch centers.
In addition, shapes are manufactured with two lengths of channel welded together back to back, or three or four welded together in various patterns, to form stronger structural elements.
Materials
Strut is normally manufactured out of sheet steel, with a zinc coating (galvinized), paint, epoxy, powder coat, or other finishes.
Somewhat more rarely, strut channel is manufactured from stainless steel or aluminum alloy, in cases where the strut rusting might become a problem (outdoors, chemical facilities with corrosive materials) or where weight is an issue (aluminum particularly).
Interconnection
The inwards-facing lips on the open side of strut channel are routinely used to mount special nuts, braces, connecting angles, and other types of interconnection mechanism or device to join lengths of strut channel together or connect pipes, wire, other structures, threaded rod, bolts, or walls into the strut channel structural system.
Usage
- StrutHanger.JPG
An overhead electrical wire hanger manufactured from two lengths of strut channel and two lengths of threaded rod.
- StrutJoint.JPG
A length of standard half-slotted strut channel used as a brace, connected to a length of half-channel mounted directly to a wall, joined with a purpose-built channel connecting steel angle.
- StrutShelf.JPG
A shelf supporting electrical conduit and pipe, manufactured from strut channel
Strut channel is used to mount, brace, support, and connect lightweight structural loads in building construction. These include pipes, electrical and data wire, mechanical systems such as ventilation, air conditioning, and other mechanical systems. Strut channel is also used for other applications that require a strong framework, such as workbenches, shelving systems, equipment racks, etc.
References
- ↑ 1.0 1.1 1.2 Erico Product Catalog, 2009, Chapter 15 Strut, Fittings, and Accessories, [1]
- ↑ Grainger Strut Channel catalog, accessed 2009-08-05
- ↑ National Electrical Manufacturers Association page on Strut Channel, accessed 2009-08-05
- ↑ Cooper B-line Strut Catalog, accessed 2009-08-05
External links
- The china strut channels industry, from njwanze.com
Unistrut International Corporation - The original inventor of "Stut" metal framing in 1923. Additional information can be found at www.unistrut.com
