R & D
A very important part of making a UV system work, is the quartz parts. Important because all UV energy has to pass through this, with a loss - Quality determines how big the loss will be. First it has to pass the lamp it selves and then the "window" that closes the housing. The right choice of quality is the key to success. As the price goes down very fast on decreasing quality, it is easy to make a poor choice.

The lamp of course has to be made of the best quality. All of the UV energy comes from this source and a loss at this stage would make good work on the rest of the system without any value. Lamp quartz comes under different trade names (Suprasilâ, Ilmasilâ, GE124), but can all withstand the temperature needed for the plasma to radiate UV down below 200 NM. Further none of these will block out UV-C as long as you keep the surface temperature under 1000-1050 degree C. Very cheap lamp types, make of poor quartz quality, has quite a high loss of UV; and you will not be able to determine why your system performs badly.

The window, which all the energy has to pass, should also be of very high quality. Suppliers of the same material as mentioned above, can supply plates or cut-tubes in the right dimension and the right quality. Surely it seems obvious not to choose a better quality for the window than you made on the lamp-type. But if your lamp-quartz cuts of 60% at 220 Nm and the window does the same, the result is almost no UV in the low range (60% of 60% = 36%).

Here is shown the difference between two types of quarts - loss in the UV-C area. Red- GE214P and pink GE124. Almost the same difference is seen between Ilmasil PS and Ilmasil PN

It can be seen that there is quite a big loss using GE124. Using this as both lamp and window material would make you loose app. 50% of the UV-C

Another use of quartz in a UV system is as reflector material, coated with a layer that reflects UV light (Cold mirror).  As this material is not supposed to transmit UV light, but only needs to withstand the high temperature there are several options for flat or circular types of material. Some common trade names is "Duran", "Robax" or "Borofloat" and are glass with a max. working temperature from 400-700 degree C - depending on the type.

For further information: Contact

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