How To Test The Sensitivity Of The Needle Checking Machine?

"Metal needle detector" is also known as needle checking machine, needle checking machine, needle detector, metal detector and so on. According to its classification, there are three main categories: pmission type (continuous), platform type and hand-held type.

Many garment enterprises and processing factories have purchased needle checking machines. However, due to improper storage and personnel changes, the original technical data of the needle checking machine (such as instructions and test cards) were lost, causing factories to use needle checking machines everyday, but they did not know their own.

Generally, enterprises can only temporarily seek help from needle manufacturers, but not all the reception personnel of needle manufacturers.

How to test the sensitivity of the needle checking machine?

Under normal circumstances, the brand name checking machine on sale in the market has already set a good sensitivity before leaving the factory.

The sensitivity of the needle machine can be roughly divided into two periods.

Period 1: analog circuit checking machine period

Most of the needle machines produced before 2004 were still in imitation stage because of the production technology, and analog circuits were mostly used. The machine performance and sensitivity could not reach a high level.

During this period, the needle function detected the 1.2mm diameter iron ball even a very good needle machine.

Nowadays, many second-hand needle checking machines and most of the needle inspection machines purchased by most manufacturers are products of that period.

For this type of needle checking machine, many textile enterprises have used several levels of needle to describe the sensitivity of the needle checking machine.

Because there are several levels of needle, the reason is that the needle machine is the analog circuit at that time. The sensitivity of the inspection needle machine is mainly to see the sensitivity indicator on the control surface. (usually there are 10 files, one level is quite old, and so on).

Period 2: digital circuit needle checking machine period

Since 2004, due to the advent of the digital era of needle checking machines, the production technology of some needle manufacturers in China has been greatly improved. The production of needle checking machines made by some regular needle maker enterprises has the highest sensitivity. A stable nine point test has been made to detect the diameter of 0.8mm iron balls (judging by industry standard channel height 12cm nine point test method).

At this time, the standard test card is used as the sensitivity test standard.

Standard nine point inspection machine sensitivity test method

Before that, we suggest that we prepare the standard test card and the test holder. We should select the appropriate test card according to the height of the needle machine Longmen (probe), and at the same time prepare to wipe the mechanical stitch (towel best) of the needle checking machine.

For the needle machine that has been used, wet and wring the water for the long cloth (towel), adjust the sensitivity to the lowest gear, start the machine to run it, and straighten the conveyor belt with any long cloth, and wipe the dirt on the front side of the conveyor belt.

So that the conveyor belt to run a few rounds until the conveyor belt without dirt (if the conveyor belt is particularly dirty, you can wipe the long cloth after many times to wipe or use industrial alcohol, anti-static belt cleaning for scrubbing).

Then stop the machine, clean up the long cloth, wring dry, try to put the long cloth under the conveyor belt (reverse), grab the two sections of the conveyor belt, and run the machine to wipe the dirt on the back of the conveyor belt.

First, after cleaning the conveyor belt, we use the nine point test to check the mechanical sensitivity of the needle.

First we put the standard test card directly on the conveyor belt and start the needle checking machine. If we can detect this test card, we will send out the alarm and stop it and go back to normal.

Secondly, we will then insert the standard test card into the middle part of the test card holder (also can find metal free material), put the rack embedded in the standard test card into the running belt conveyor, and check the needle function to detect the alarm and stop the machine to return to normal.

Finally, we insert the standard test card into the top part of the test card holder and put the rack embedded in the standard test card into the running belt conveyor. If the tester can detect the alarm and stop it, it will be normal.

It is worth noting that the above three steps require the detection card to be placed in different positions of the conveyor belt and checked one by one after three different points.

After the above three step test methods can detect the test card and alarm the downtime, the machine can be used normally.

(Note: the sensitivity of the needle checking machine is the diameter of the standard test card used. Nowadays, the iron ball test card with diameter of 0.8mm, 1.0mm, 1.2mm, 1.5mm and 2.0mm is used.

The type of test card should be used for the actual sensitivity of the needle, depending on the specific product and the height of the needle exit machine.

The sensitivity verification of the above needle checking machine must be carried out once every three hours, and the written results of the calibration results will be recorded in writing, and will be supplied to the customers for inspection.

If nine point test is carried out to verify that the sensitivity is not up to the requirement of the customer, the sensitivity of the needle checking machine can be increased.

If the sensitivity of the needle machine is high, it still can not meet the customer's requirements. We suggest that we contact the supplier to solve or replace the machine.

Reminder

The nine point test is that the sensitivity of each point is different.

The sensitivity of the two parts near the probe is the highest and the center point is the lowest.

The nine point test is used to confirm the minimum point sensitivity of the needle checking machine. The result obtained by the nine point test method of the needle machine is the real sensitivity of the needle checking machine.

It is worth noting that some manufacturers of the needle manufacturers are using the sensitivity of the conveyor belt as the standard to mislead the users to purchase.