May 2009 Vol. 236 No. 5

TechNotes

The TM (ten-minute) Tap Removal System

The process of removing old clamp-on gas service tees is long and tedious, taking a four man crew a minimum of three hours to complete; that’s three hours or more for each removal.

There are several steps involved in this process, and in the event that service can’t be interrupted downstream, a bypass has to be installed.

A half-stop is welded on each side of the tap that is being removed to control the flow of gas and a bypass hose is added. Once the bypass is operational, the service connection is removed; a patch is welded over the tap site, or a cylinder of pipe is welded in place.

Another method less timely used by some companies is to remove the cutter, then drive a punch into the tap hole, grinding off the tee and welding the punch into the hole. Also, some tees are abandoned by running the cutter down and welding up the outlet.

There is a safety issue with the process of removing the cutter and driving in a punch. The crew is exposed to a gaseous atmosphere in an upper or lower explosive limit where gas could ignite. While the punch is being driven into the hole, there is a chance for the punch to dislodge and be ejected by the pressure, again putting the crew in a dangerous atmosphere with chance of ignition, z potential danger for crew and the public. Left in the ground are possible points for leaks and protruding obstacles from the main line which pose a safety concern for any gas company or contractors digging along the line because they are not aware of the fittings now protruding from the main line.

When struck by excavation equipment this could cause an interruption in gas flow, completely shutting down part or all of the system, costing the company many man hours and money until now.

Mesaba Pipeline Products Inc. has introduced a product designed to be safe, save company time and money. It is called the TM (ten-minute) Tap Removal System. This product is designed for retiring and removing clamped on or welded on steel service tees in a gas distribution system under no-blow conditions. The system will allow field personnel to remove potential excavation obstacles and return the pipe to near its original condition. The system will do a better job in a fraction of the time and in nine easy steps, changing the pipeline industry’s protocol forever. The tools included in the system are a way to control the flow of gas, remove the cutter and plug the cutter hole in a no-blow situation.

The system has been tested by the Gas Technology Institute. It was designed by a certified API 1104 welder and AWS-certified welding inspector who has spent 30 years working in the gas distribution industry, both welding and inspecting gas pipelines. After witnessing and experiencing first-hand the dangers of live gas situations, he knew there had to be a safer way to abandon mechanical and weld on-service tees.

By using that working knowledge, Mesaba has designed a tool that controls the gas flow, removes the tap, plugs the old punch hole in a no-blow situation. There is no need for half stops or a bypass or trying to drive a punch into a tee while gas is blowing. The TM System completely eliminates the welded patch and the need to weld in a cylinder of tested pipe. Also gone are the abandoned tees that are done by running the cutter down and welding up the outlet. No more potential leaks and no surprises for anyone trying to expose the gas system safely.

Again, the standard tap removal takes four men a minimum of three hours to complete a stop and bypass for removal of the old tap. Though less timely than a bypass, the use of a punch on live gas is a safety concern. The TM System takes ten minutes to complete, saving your company time and money with a minimal amount of tools and labor by not turning it into a major project.

For more information visit www.mesabapipelineproducts.com.