Steve Vick International (SVI) is delighted to announce its’ PE Electrofusion Live Head, a successful NIA project in collaboration with Cadent Gas, has been approved for use.
The new PE Live Head is internally electrofused, offering a streamlined shape with the Live Head sitting flush with the PE. This allows for easy insertion and makes negotiating bends less challenging. The purpose of a Live Head is to allow gas to flow from the host main into the PE coil during Live Mains Insertion. Both the plastic, and metal designs are the only approved fittings for this.
Although the PE Live Head has been developed to specifically assist with the insertion of 90mm PE into a 4”, where the annulus is narrower, it can be used in any size of host main. In an ideal world, with Live Mains Insertion, you would insert 75mm inside a 4” main, however with capacity in the mains stretched and with Hydrogen on the horizon, SVI are seeing more 90mm being inserted into 4”, hence the development of the new PE Live Head. When inserting 90mm inside a 4”, the annulus is 63mm which is usually the same size as an overland PE bypass or the internal bore of a bypass trailer. Using the PE Live Head reduces waste of a PE bypass or hire charges for bypass trailers.
Using a metal live head for 75 in a 4” or 125 in a 6” isn’t a problem but for 90mm in 4”, when you screw the metal live head into the PE, it can cause the PE to expand, making the first metre more rigid and more prone to getting stuck during the push. The PE Live Head overcomes this because when installed, the PE doesn’t increase in size, resulting in the leading end being more flexible.
The new PE Live Head was successfully trialled under a G23 before being approved for use by Cadent Gas. Other GDN’s are currently trialling the new fitting, including Wales and West Utilities and SGN.
There are many benefits to using Live Mains Insertion rather than more traditional methods and the new PE Live Head and Metal Live Head are fundamental to this process. During Live Mains Insertion for example, customers are off gas for a significantly reduced amount of time as only one purge and relight is required. LMI can also potentially achieve longer pushes which could mean less insertion pits, resulting in less reinstatement costs for the Gas Distribution Networks.