Our old customer Mr. Zhang called last week and asked: "How can you use your ultrasonic flaw detector for packaging machines accurately? The weld of my new equipment always feels wrong." This question made me realize that many colleagues may underestimate the importance of using flaw detection equipment correctly. Today, based on our more than ten years of field experience, let's talk about the correct way to open the ultrasonic flaw detector for packaging machines.
As the "stethoscope" for packaging equipment detection, the ultrasonic flaw detector for packaging machines plays a key role in weld defect detection. I remember that when I helped a food factory in Jiangsu to inspect equipment last year, their operators habitually moved the probe randomly, resulting in the key welding points of the transmission shaft being missed. Later, we taught them to use the "three-point positioning method" - first fix the inspection area, then scan along the M-shaped path, and finally use the oblique probe to recheck the suspicious position. This method successfully found three tiny cracks that were difficult to see with the naked eye in subsequent quarterly inspections.
The most easily overlooked thing in daily operations is the use of coupling agent. Xiao Wang in our workshop made this mistake. One day, he was in a hurry to get off work and directly used tap water instead of professional coupling agent, causing the waveform displayed by the flaw detector to jump like an electrocardiogram. Later, we switched to our factory's special high-temperature resistant coupling paste, which not only stabilized the signal, but also improved the anti-rust performance of the equipment casing. It is recommended that you calibrate the flatness of the probe contact surface every six months, just as simple but important as wiping the screen before applying a film to a mobile phone.
When encountering complex working conditions, such as detecting a packaging machine silo with multi-layer composite materials, our engineers will use the "dual-frequency switching" mode. First, the abnormal area is located by penetrating the thick-walled structure with low frequency, and then the defect type is accurately analyzed with high-frequency mode. A typical case was just handled last week: intermittent air leakage occurred in the vacuum chamber of a pharmaceutical packaging company. This method was used to discover the pore group hidden in the third layer of steel plate.
Three "nos" should be remembered in maintenance: do not let the flaw detector stay in a high temperature and high humidity environment for more than 2 hours; do not scratch the display screen with hard objects; do not work continuously for more than the manufacturer's recommended detection time. Our maintenance department often receives cases where equipment is retired early due to ignoring these details. It is recommended to perform a system self-check every 200 tests. This frequency can ensure safety without affecting work efficiency.
Judging from the cases accumulated over the years, the correct use of non-destructive testing technology can help enterprises avoid more than 70% of unexpected downtime accidents. A few days ago, I visited a customer in Zhejiang. Their workshop director said that since the standardized use of ultrasonic flaw detectors for packaging machines, the equipment overhaul cycle has been extended by a full 8 months. This reminds me of what my master often said: "Flaw detectors are not decorations, but safety sentinels on the production line."
