Pipe Plugs????? are you trying to make a flame thrower?

pipe a fill 1/4th part in 7 mins and pipe b in 7.5 mins hence both tank will fill 1/4th of tank in 7+7.5/4 = 3.6 mins

To find this you need to imagine the pipe slit straight down and rolled out. At this point what you have is 10 right triangles, with the base of the triangle being the circumference of the pipe and the height of the triangle being the height of the pipe divided by the number of wrappings. The hypotenuse then is the length of one wrapping. Multiply that number by the number of wrappings and voila, you have the length of the wire.

A pipe clay triangle's use is similar to a gauze mat; to steady/hold apparatus on a tripod while usually they are being heated by a Bunsen burner.

What you describe MAY be part of the EGR valve assembly. I'd need to know more about what pipe is broken, where it is and what it does before I could give any more of a guess.