Nine point detection method of needle detector

- Dec 11, 2019-

Standard nine point needle machine sensitivity test method: (nine point test method)

1. Prepare standard test card and test card holder (select appropriate test card according to the height of mechanical gantry (probe) of needle detector);

2. Prepare to wipe the long strip cloth of needle detector (towel is the best);

For the used needle checking machine, the strip cloth (towel) is moistened with alcohol, and the sensitivity is adjusted to the lowest level. Start the machine and let it run. Pull the strip cloth straight and press either end of the conveyor belt to wipe the dirt on the front of the conveyor belt, so that the conveyor belt can run for several circles until there is no dirt on the conveyor belt. Then stop the machine, clean and dry the strip cloth, and try to put the long cloth on the conveyor Pass through the lower side (opposite side) of the belt, grasp two sections of the belt with both hands, and start the machine to let it run to scrub the dirt on the back of the belt.


After scrubbing, use nine point test method to check the mechanical sensitivity of the needle. First, use standard test card and bracket to check the upper, middle, lower, left, middle and right of the needle. Start the needle detector, and the needle detector will send an alarm to this test card and the machine will stop and reverse normally.

The sensitivity of the needle detector is the diameter of the standard test card used. Now, the iron ball test card with diameter of 0.8, 1.0, 1.2, 1.5 and 2.0mm is mostly used. The actual sensitivity of the probe shall be determined by the specific test products, export international and channel height of the probe machine. The sensitivity verification of the above needle detector shall be carried out every three to four hours, and the verification results shall be recorded in written form for the customer's inspection.

If it is found that the sensitivity can not meet the customer's requirements after nine point test, the sensitivity of the needle detector can be increased. If the sensitivity of the needle detector still fails to meet the customer's requirements, it is recommended to contact the supplier for solution or replacement.