Method of hot tapping a pipe for installing ionic flowmeter transducers

A method of hot tapping a pipe and permanently installing a pair of carriers for use with sonic flowmeter transducers comprising the following steps:

• (a) permanently securing first and second alignment fixtures to an outside wall of a pipe so the alignment fixtures are aligned with each other along and parallel to a longitudinal axis of the pipe and are an appropriate distance apart;
• (b) removably securing a drill bushing within the first alignment fixture;
• (c) removably attaching a hot tapping device equipped with a removably attached drill assembly to an angled surface provided on the first alignment fixture;
• (d) opening a valve provided on the hot tapping device and moving a drill bit provided on the drill assembly toward the pipe until the drill bit abuts the pipe;
• (e) rotating the drill bit to create a hole in the pipe;
• (f) moving the drill bit away from the pipe until the drill bit clears the valve;
• (g) closing the valve to isolate the drill assembly from the pipe and opening a pressure relief valve provided on the valve in order to relieve pressure on the drill assembly;
• (h) removing the drill assembly from the hot tapping device;
• (i) securing a cleaning assembly to the hot tapping device;
• (j) opening the valve and moving a magnet provided on the cleaning assembly toward the pipe until the magnet bottoms out in the device and attracts magnetic metal shavings which adhere to the magnet;
• (k) moving the magnet away from the pipe until the magnet clears the valve;
• (l) closing the valve to isolate the cleaning assembly from the pipe and opening the pressure relief valve in order to relieve pressure on the cleaning assembly;
• (m) removing the cleaning assembly from the hot tapping device and cleaning the magnetic metal shavings from the magnet;
• (n) repeating steps (i) through (m) until the hot tapping device is cleaned of magnetic metal shavings;
• (o) securing an extraction assembly to the hot tapping device;
• (p) opening the valve, moving the extraction assembly toward the pipe, engaging the drill bushing with the extraction assembly and removing the drill bushing from the first alignment fixture;
• (q) moving the drill bushing away from the pipe until the drill bushing clears the valve;
• (r) closing the valve to isolate the extraction assembly from the pipe and opening the pressure relief valve in order to relieve pressure on the extraction assembly;
• (s) removing the extraction assembly from the hot tapping device and replacing the extraction assembly with an insertion assembly to which a first carrier is removably attached;
• (t) opening the valve, moving the first carrier toward the pipe by means of the insertion assembly and securing the first carrier to the first alignment fixture;
• (u) opening the pressure relief valve to check whether the first carrier is properly secured to the first alignment fixture;
• (v) removing the hot tapping device from the first alignment fixture;
• and
• (w) repeating steps (b) through (v) for the second alignment fixture and employing a second carrier instead of the first carrier.