Analysis of the use of LED guardrail environment and protective measures

First, LED guardrail industry quality

Second, the conventional protective measures can do it?

Looking at the protective measures of the LED industry guardrail tube, basically external protection at both ends of the plug, from the work environment of the guardrail tube analysis, according to the different use of the area, the guardrail tube can withstand: high temperature, cold, sun , rain, dry and other harsh environmental factors test, it seems to be foolproof at the factory, but the use of the process but the problem continues, and where is the root cause? In fact, many companies ignore a few details before giving birth. (1): In the warranty period, the early failure rate of components is about 0.3%-1%. The actual damage rate will vary depending on the quality control of the components. (II): The corrosion rate of moisture and acid-alkaline substances in the air in the guardrail bar due to the temperature change is about 4%-7%. (C): Unexpected expansion of the tube shell, blocking The damage rate caused by the head degumming is about 2%-6%, and the specific damage rate will vary depending on the manufacturer's choice of housing materials. It can be seen that the protection of the circuit board inside the pipe is the fundamental solution to the problem. Conventionally, only the measures for protecting the external water can not achieve the real protection purpose of the guardrail pipe, and can not meet the annual damage rate of the guardrail pipe.

Third, the comparison of conventional protective measures

Conventional shell protection basically uses the following three methods.

The first kind of protective measures: Ultrasonic bonding plugs and shells, this is the most sensible approach, but also the most undesirable method ultrasonic bonding, it looks like the appearance of the product is more beautiful, the protective effect of the finished product is also very good, but sticky The materials at the junction are damaged by ultrasonic waves. The components on the circuit board inside the tube are also damaged by ultrasonic waves. The early failure rate of electronic components will increase exponentially, and the protection of the circuit board is not solved at all. The more frightening thing is: After working in a harsh environment for several months, the thermal expansion and contraction of the pipe causes the water leakage rate caused by the cracking to reach 30% to 60%. The consequences are very serious.

The second protective measure: viscose adhesive plugs and pipes, which is a cost-saving method for low-end products. If the viscose is used properly, attention must be paid to the details during production. This protective measure can still play a good external role. Protective effect. But also can not be circuit board protection and the appearance of the finished product is ugly, in the use period, the bad environment will make the pipe and plug degumming damage rate of about 2% -4%.

The third kind of protective measures: silicone ring connecting plug and pipe. The appearance is beautiful and the protection effect is good. It is the best choice for the above three types of shell protection. However, the cost is high and the low-grade products in the price competition market cannot be selected. This method solves the problem of the protection of the connection between the plug and the pipe.

Fourth, LED guardrail tube " longevity "

The above three protective measures can only solve the problem of the protection of the plug and the pipe connection, but it cannot solve the problems such as: the pipe material does not withstand the cracking water formed by the erosion of the harsh environment; the air existing in the pipe material condenses under low temperature environment. The formation of bead damage to the circuit board and other issues.

Many companies that are committed to high-grade high-quality guardrail tubes are also seeking solutions to airborne erosion of circuit boards within the tubes. The basic methods are nothing but the following four approaches.

The first way is to pump air from the tube and inject inert gas at 1 atmosphere. As this solution cannot solve the mass production of the company, it cannot solve the problem of external rainwater entering due to pipe bursting. Therefore, there is no enterprise choice.

The second way: vacuum impregnation of the circuit board inside the pipe and the contact between the circuit board inside the pipe and the air and water vapor may seem desirable. However, it actually does not work. To achieve the desired effect, the insulating paint needs a certain thickness. In the use of the guardrail tube, the coefficient of thermal expansion and contraction of the electronic component cannot be consistent with the insulating paint, which will cause damage to the electronic components and cause the early damage rate of the component to increase exponentially, and when lighting the guard tube At the temperature, the volatile components in the catalytic insulating paint chemically react with the casing PC tubing, causing damage to the tubing in a very short time.

The third way is to fill the pipe gap with special materials. The volume of the circuit board inside the guardrail pipe accounts for about 1/5 of the volume of the pipe . The cost of the fill material has a great influence on the price of the product. It also increases the weight of the guardrail pipe and affects the light-emitting effect of the guardrail pipe. Therefore, it is not desirable.

The fourth scheme: Apply special protection. This set of solutions is now only used in the products of Beijing BingSoft Optoelectronics Technology Co., Ltd. and obtained national patent. Patent No.: ZL200520113616.6. After the circuit board is specially protected, the surface of the components does not show any protection. Traces, brightness of the lamp without any loss, and can achieve IP67 protection level, the protective layer can withstand -40 °C -200 °C temperature changes, test results show that ultra-thin protective layer in the long-term work will not affect the circuit board The electronic components on the long-term stability.

V. Conclusion

In order to reduce the annual damage rate of the LED guardrail tube, only the shell protection is not enough, and the circuit board inside the tube must be effectively protected. The damage rate of the guardrail tube is only the early failure rate of electronic components in any harsh climate environment. In the case of effective control of raw materials, the annual damage rate of the guardrail pipe can be controlled within 1% , which greatly saves the huge waste caused by the high damage rate.