Steps to control the working process
To confirm the work process, the data must be clearly recorded!
If you want to control the printing process, you must measure every measurable variable. If the data is not properly processed, it is in vain, so you must design a data entry form for each printing project to record. You must establish some baseline parameters and record the results to supervise the process. Compare the measured data with the baseline data. When you start a project, you must set up a "first aid window", and you must know which parameters limit your maximum and minimum limits. When you know these limits, you can get some hints and indicators during the troubleshooting process.
The laser meter walks through the production line with the product at the same time so that you can get the data you need as soon as possible.
You also need to be careful from time to time and check the production line speed, the number of lamps, settings, UV dose and maximum energy value.
As your database grows, you can predict the diagnostic results you need and add the variables you need to pay attention to. At the same time, you can also predict when repairs are needed and plan for them to be carried out during the downtime.
Don't speculate, but must measure
Because the process results are constantly being repeated, you must measure your printing process parameters without reference.
Establish baseline parameters:
So what needs to be measured and checked? Among many projects, the following projects are more important in the UV printing process control:
-The digital flow meter accurately measures the speed of the conveyor belt and the production speed
-Hour meter shows the age of the light
-The ammeter calculates the amount of current flowing through the lamp
-Appropriate UV data measurement and monitoring equipment
-Temperature sensor capable of measuring the highest temperature
In addition, there are other accessories that affect the output of UV lamps, such as ballasts, current supply, capacitors, magnetrons, and line voltage, but these are not a complete maintenance manual.
speed
Using a cheap digital flow meter can accurately measure the production speed. It's not easy to rely on the built-in speed monitors because they are often inaccurate. Use the data from different conveyor belt speeds to create a graph showing the set speed and the actual speed. Until you get a digital flow meter, you can use the chronograph to calculate the conveyor belt speed.
As with other parameters, the belt speed needs to be measured permanently.
Hour meter
This is the time when the lamp has been turned on and as an indication when it needs to be replaced, but these calculation tables will not tell you how many times the lamp has been turned on. They also cannot tell you the status of the lamp being turned on, the heat and cooling effect of the lamp, the time it was last cleaned, or whether the lamp was switched evenly. It will not tell you whether the lamp is properly used and no impurities are left on the quartz surface to form a hot spot, which will eventually become a weak spot.
The hour meter will tell you when the lamp was turned on, but unfortunately it will not tell you if there is enough UV energy to completely dry your product.
Use the hour meter as your lamp to make a corresponding display of quality.
Ammeter
An ammeter is an instrument that calculates how much current is supplied to the lamp, so it is a measure of how much current is supplied to the lamp. Since the lamp tube cannot convert energy into UV with 100% efficiency, in fact, only a small part of the total energy will be converted into UV output, and only a small part of UV will make the ink dry. Therefore, the ammeter is not a good UV measuring instrument. However, the data obtained can play a role in troubleshooting.
watt
The display unit of the lamp is Watt / cm (W / cm) or Watt / inch (W / in). This is the energy emitted by the length of the lamp, but this is the energy input, and a very small part will be converted into UV energy.
The watt number only shows the energy loss required by the light pipe, but it does not tell you the amount of UV energy output.
The watt of the lamp will be converted into UV, and the visible light will be converted into infrared (heat energy).
Although the lamp is operating as usual, the lamp will gradually age and the energy output will continue to decline. So where does the energy go? It is not UV but thermal energy.
Therefore, we need to regularly measure the UV output of the lamp!
Many people confuse Watt and Joules.
The intensity of the lamp will be measured in MilliWatts (mW). MilliJoules (mJ) is the cumulative amount of MilliWatts over a period of time. The equation for calculating J / cm2 is:
UV lamp
When you are entrusted with a job, you must consider the variables and not guess the result. As much as possible, get the required UV energy information from your ink or coating supplier to make the ink dry. What energy can activate the initiator? When this chemical formula occurs, these data will be known.
Most chemical suppliers will have UV measuring instruments, so they can tell you what will happen under dry conditions. The UV instrument supplier you purchased will have the spectral output information, intensity and temperature data at the time of use. With these data, you may be looking for lamps that match your spectral response graph.
Reflector
Most people will underestimate the important role of the internal reflector of the UV emitter. The mirror can only reach 70% of the energy to the dry surface, and the rest will be directly emitted by the lamp itself.
When the dried product passes through a strong UV and thermal energy space, the UV emitter will attract dust and smoke, causing the mirror to become dark. So the UV spectrum will be lost, even if the visible light is still bright. If you have instruments that measure different UV wavelengths, you will find that shorter wavelengths are more likely to flow away and weaken. In this way, you can predict when you need to clean the system, which is better than if you only observe long wavelengths.
UV measurement and observation method
The radiometer is a very effective device for measuring UV radiation parameters. The radiation parameters include such as the UV maximum energy, UV dose, UV spectrum, focal point, efficiency of the reflector and the highest temperature. They can provide you with conditions during the drying process.
The connected UV monitoring system can permanently provide relative data and data, while the German UV DESIGN can also provide a series of recording and monitoring instruments.
Maintenance
Periodic maintenance is very important, so it must be properly arranged. It helps the drying system to remain intact, ideal performance and prevent unwanted failures. When conducting management and maintenance, you must pay attention to and read clearly the supplier's information.
When the repair is completed, the drying system must be turned on again to stabilize it.
Once again, the data is measured. If the data improves, no further action is required, but if the digital display is out of specification, the lamp, reflector, or both need to be replaced.
Regular measurements and records
If you can make regular measurements, it will definitely reduce the problems of your UV drying system.
If you can properly process and record the obtained numbers, you can find a principle for comparison, otherwise you just make records and measure indiscriminately.
In fact, the best use for measuring and recording your drying system is to enable you to improve quality to meet customer requirements. At the same time, you can avoid producing bad products.
Although digital recording is a very time-consuming task, it guarantees that you will get the rewards you deserve.
The UV drying system is not magic, but science!
Anping County Hua Guang Wire Mesh Production Co.,Ltd , https://www.hgwirefence.com