Take the pan, and drill a hole in the centre of each pan. After drilling holes in the centre, drill two more holes at least 6 inches apart as well.
Tie a knot at one end of the nylon cord, and pass it through from the inside of the pan to the outside. Once you have passed the cord through the centre hole, and then pass it from the adjacent holes as well before inserting it back into the pan. Tie a knot at the other end of the cord so that the cord does not slip out of the pan.
Now take the PVC pipe flush, and position it over the hole of the pan. Close its bottom end with a PVC cap, and then attach a cap over the upper end as well. Mix concrete according to the instructions written on the manual. Now remove the cap board, and add concrete that will be able to hold up the pipe properly. Repeat the same process on all the other pans as well.