That should work just fine. Just make sure the thermocouple tip has good consistent contact with the pipe. I think the electrical tape will be good for this because it is a bit stretchy. Just give it a nice tight wrap.
The T400 will log one second intervals for at least 48 hours on a fully charged battery. Usually about sixty hours if the backlight is off and and you're logging at ten second intervals. If you need longer run time, the device can be powered via USB. A wall power adapter is best. Note that many USB battery packs will turn off if current is drawn below a threshold to avoid power leakage. The T400 draws very little current and some packs will turn off after the T400 battery is charged.
In principal, the T400 can log data until you reach the 2GB FAT16 file size limit. With a one second time interval this would take upwards of a year. Oh boy!
UPDATE: 41,782,954 lines of
00:03:11, 22.69, 23.08, 132.43, 200.43, 25.25 is 1.8 GB. This is 483 days of logging at one second intervals or over thirteen years in ten-second intervals!