||50 um -10 mm
Each coated pipe section shall be electrically tested for flaws in the coating using a suitable holiday detector,The detector shall impress a minium of 6000 V for pipe section or 12000 V for specials and weld joints.
The electrical inspection shall take place on the inner layer tape before the outer layer tape is applied.if holiday is detected,it shall be repaired as per specification.
So the Holiday testing is very important . every porject need it , the holiday detector is important tester for the pipes.