This reminds me of skin-effect electrical heat tracing. In this application, small tubes are welded longitudinally onto the proces pipe and then a conductor is pulled through. The physics of the heat tracing is that the inductance of the pipe causes the pipe wall to be heated when an alternating current is passed through the conductor.

If this is what you are doing, then the welds are not pressure-containing, and may be treated as attachment welds. Since the small tubes and the process line are both within the insulation blanket, and have continuous physical contact along the length of the pipe, and bear no structural load, there are no loads to consider other than the (small) additional mass as it applies to seismic analysis. Therefore, as attachments only, the welds are subject to the same rules as the welds for a lifting lug one would use solely to lift the pipe into (or out of) place. And, with no structural loads to be applied, your basic need is for a sort of electrical continuity.

If this is NOT what you are doing, please disregard my comments.