BENEFITS OF ONSITE FABRICATION OF WIRE MESH CABLE TRAY FITTINGSPosted On: Thursday 3rd May 2018 Back to Blog Listing
BENEFITS OF ONSITE FABRICATION OF WIRE MESH CABLE TRAY FITTINGS
It is well established that wire mesh cable tray saves considerable installation time and labour cost when compared to conduit. Wire mesh requires fewer parts, no preformed ﬁttings and fewer tools. Even more signiﬁcant is the ease of creating wire mesh ﬁttings on site, which gives complete freedom in routing combined with exceptionally fast installation.
Because wire mesh is highly conﬁgurable in the ﬁeld, it does not require specially fabricated components to make corners, T’s, up/ down angles or intersections. Installers simply cut the mesh to any desired conﬁguration. Further, these installation steps do not require as high a degree of training as the “art” of conduit bending.
Wire mesh requires fewer parts, no pre-formed ﬁttings & fewer tools
OFFSITE VS. ONSITE FABRICATION
Although prefabricated ﬁttings for wire mesh tray are available, they do not usually provide a productivity beneﬁt – and they can actually slow the progress of a job. That’s because prefabricated ﬁttings can cause the contractor to lose onsite ﬂexibility. Electrical professionals are often the ﬁrst trade to lose dedicated space due to changes in conﬁguration. Sewer, sprinkler and HVAC are given priority over electrical services, and electrical is expected to work around them. The location of these obstacles frequently differs from what is shown on the original drawings.
Wire mesh tray is uniquely suited to working around obstacles in the ﬁeld. Standard lengths of tray can be cut and bent to create any bend, sweep or level. On the other hand, the contractor who orders prefabricated ﬁttings based on the drawings may well arrive onsite to ﬁnd that the ﬁttings do not match real-world conditions and new ones will need to be ordered.
In order to change direction using a prefabricated ﬁtting, the installer must cut a section of installed tray because the straight tray rarely stops exactly where the ﬁtting is needed. This process requires cutting through the entire tray, locating the correct ﬁtting, bolting it in place and attaching another section of straight tray. In contrast, ﬁeld fabrication requires that only a portion of the tray section be cut, bent and bolted to make the appropriate changes now.
Onsite fabrication means no downtime waiting for additional components. If additional tray lengths are required, they can be ordered from the distributor for immediate delivery, while the right size prefabricated component may not be in stock. The contractor beneﬁts from ready access to stock items versus made-to-order components.
Contractors gain ﬁnancial advantages due to the fact that components can be easily fabricated onsite. Contractors are well aware that installed runs of straight sections of tray have pathway interference issues as often as every 20 feet. As a result, tray must be cut to length in nearly every instance where a ﬁtting will be installed. There is almost never the opportunity to “simply bolt on” a factory-fabricated ﬁtting without ﬁrst cutting a straight length of tray. This is where the advantage of ﬁeld-fabricated ﬁttings truly shines: By the time the tray is cut to length, most of the labour is already completed. The sample bill of materials shown to the right demonstrates the labour savings associated with ﬁeld-fabrication ﬁttings compared to factory-made ﬁttings. Higher labour units required to install factory-fabricated ﬁttings (highlighted) translated into 29% more time for the total installation
Wire mesh is a unique cable management system due to its inherent cost-saving potential, including the ability to create ﬁttings in the ﬁeld. This approach is shown to be faster than using factory fabricated ﬁttings that require cutting the tray completely and bolting on a ﬁtting, compared with a partial cut to the tray to create the exact ﬁtting required. This ability to create ﬁttings onsite, rather than ordering manufactured ﬁttings, is an important consideration for electrical contractors looking for ways to save time and reduce cost. Industry standard cost comparisons conﬁrm that ﬁeld-fabricated ﬁttings require less time and labour to install. Further, wire mesh tray is also designed so that ﬁeld modiﬁcations do not compromise UL classiﬁcation.
DP Building Systems are a distributor of Legrand and Cablofil, if you require any information or support please contact DP Building Systems technical team on 0121 706 7777 or firstname.lastname@example.org