Quality control of the best quality printing

2022-08-17
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Quality control of high-quality printing

steps to control the working process

if you want to confirm the working process, you must record the data clearly

if you want to control the printing process, you must measure every measurable variable. If the data is not properly processed, it will be in vain, so you must design a data input sheet to record each printing project. You must set some baseline parameters, record the results, and 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 know which parameters limit your maximum and minimum limits. When you know these limitations, you can get some tips and indicators in the troubleshooting process

the laser meter and the product go through the production line at the same time, so you can get the required data as soon as possible

you also need to pay attention to and check the production line speed, number of lamps, settings, UV dose and maximum energy value from time to time

as your database grows, you can predict the diagnostic results you need and add variables you need to pay attention to. At the same time, you can also predict when it needs to be repaired and plan it to be carried out within the failure time

don't speculate, but you must measure

because the process results are constantly repeated, you must measure your printing process parameters without reference

set baseline parameters:

so what needs to be measured and checked? Among many projects, the following items are more important in UV printing process control:

- digital flow meter accurately measures the speed and production speed of the conveyor belt

- hour meter shows the age of the lamp

- ammeter calculates the current flowing through the lamp

- appropriate UV data measurement and monitoring instrument

- temperature sensor capable of measuring the highest temperature

in addition, other accessories affect the output of UV

lamp, For example, ballast, current supply, capacitor, magnetron and line voltage, but these are not a complete maintenance manual

speed

the production speed can be accurately measured by using a cheap digital flowmeter. It's hard to rely on the built-in speed display, because they are often inaccurate. Use the data obtained from different belt speeds to set up a chart showing the set speed and the real speed. Until you get the digital flowmeter, you can use the chronometer to calculate the belt speed

as with other parameters, the belt speed also needs to be permanently measured

hour meter

this is the time when the display lamp has been powered on and as an indication of when it needs to be replaced, but these calculation tables will not tell you the number of times the lamp is turned on. They also can't tell you how the lamp is turned on, the heat and cooling effect of the lamp, the last time it was cleaned or whether the lamp has been averagely converted. It won't tell you whether the lamp is used properly without impurities left on the surface of quartz to form a hot spot, which will eventually become a weakness

the hour meter will tell you the time when the lamp is turned on. Unfortunately, it will not tell you whether there is enough UV energy to completely dry your product

use the hour meter as your lamp tube to make a display corresponding to the quality

ammeter

ammeter is an instrument to calculate how much current is supplied to the lamp, so it measures how much current is supplied to the total number of lamps. Because the lamp cannot be 2. When it is necessary to print and store the tested samples p1f2, p2f2 and p3f3, the energy is converted 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 dry the ink. Therefore, ammeter is not a good UV measuring instrument. However, the data obtained can play a role in solving problems

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 the weak rebound of this cost means that a small part of the input energy will be converted into UV energy

watt number only shows the energy loss required by the light tube, but it will not tell you the output of UV energy

the watt of the lamp tube will be converted into UV, and the visible light will be converted into infrared (thermal energy)

although the lamp works as usual, the lamp will age gradually, making the energy output gradually decline. So where does the energy go? It is not UV but heat

therefore, we need to measure the UV output of the lamp regularly

many people will confuse watt and joules

the intensity of the lamp will be in milliwatts (MW). Millijoules (MJ) is the cumulative amount of milliwatts over time. The equation for calculating j/cm2 is: UV lamp

when you are entrusted with a work, you must consider the variables in it and don't guess the result. Try to get the relevant information about the UV energy required from your ink or coating supplier to make the ink dry. What energy can activate the initiator? When this chemical program occurs, these data will be known

most chemical suppliers have UV measuring instruments, so they can tell you what happens under what dry conditions. The UV instrument supplier you purchased will have the spectral output data, intensity and temperature data during use. With these data, you may find a lamp that matches your spectral response diagram

reflector

most people will underestimate the important role of the internal reflector of UV

emitters. The reflector can only reach 70% of the energy to the dry surface, and other materials with an elongation of more than 1000% will be directly emitted by the lamp itself

when the dried product passes through a strong UV and thermal space, the UV emitter will attract dust and smoke, causing the reflector to become dark. So the UV spectrum will be lost, even if the visible light is still bright. If you have instruments, this is the best way to make the spacecraft lighter. Measuring different UV wavelengths, you can find that shorter wavelengths will be easier to flow away and weaken. In this way, you can predict when you need to clean the system, which is more accurate than when you only observe long wavelengths

uv measurement and observation methods

radiometer is a very effective tool for measuring UV radiation parameters, including UV maximum energy, UV dose, UV

spectrum, focus, efficiency of reflector and maximum temperature. They can provide you with the conditions during the drying process

the connected UV monitoring system can permanently provide relative data, while the German UV design can provide a series of recording and monitoring instruments

maintenance

periodic maintenance is very important, so it must be properly arranged. It can help the drying system to remain complete, make the performance ideal and prevent unnecessary failures. When carrying out management maintenance, you must pay attention to and read clearly the supplier's information

after maintenance, the drying system must be restarted to make it stable

measure the data again. If the data is improved, no further action is required. However, if the number shows that substandard variables appear, the lamp tube, reflector or both need to be replaced

measure and record regularly

if you can measure regularly, it will reduce the problems of your UV drying system

if you can properly process and record the obtained figures, you can find a principle for comparison, otherwise you just record and measure casually

in fact, the best use of measuring and recording your drying system is to enable you to improve quality to meet customer requirements. At the same time, you can also avoid producing bad products

although digital recording is a very time-consuming work, it can ensure that you can get the return you deserve

uv drying system is not magic, but science

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