Technical Notes #1 Can gunmetal tapping bands be installed onto PE pipe and provide a long asset life?
Simple answer to the question is No.
Gunmetal tapping bands for waterworks purposes must be manufactured to AS/NZS 4793:2009 - Mechanical Tapping Bands for Waterworks Purposes
The scope on page 4 of this Standard reads;
This standard specifies requirements for design, materials, and performance in service of PN16 mechanical tapping bands used for the connection of property service pipes to reticulation water mains.
It applies to tapping bands with and without electrical insulation, for mechanical connection to standard water mains, with the exception of polyethylene water mains that are covered in AS/NZS4129 fittings for polyethylene pipes for pressure applications. The operating temperature range is 0 to 40 degrees c.”
This excludes the use of fittings manufactured to the AS / NZS 4793 standard from being used on PE pipe. The standard clearly points out that service connections or tapping onto PE pipe should employ fittings manufactured to AS/NZS4129.