ADS Environmental Services ADS TRITON+ QR 775027 A3 - Manual (Page 282)

7-8 ADS TRITON+ Manual
Note: Consider starting the hole using smaller bits to
make pilot holes and increasing up to a the final size bit.
In addition, spray cutting oil or another lubricant into the
hole while drilling and tapping.
Drilling the hole in the manhole rim
4. Use a 3/8-inch x 16 threads-per-inch (10-mm) tap that matches
the stud thread to cut threads in the hole. Twist the tap
clockwise ¾ turn, and then back out ½ turn before continuing
deeper.