Albatross UV - UV Lamp Manufacturer

Early in the nineteenth century, a German physicist, Johann Wilhelm Ritter discovered that invisible rays of light, just above the violet end of the spectrum, would cause paper soaked in silver chloride to turn dark. He called them “de-oxidizing rays” to distinguish them from heat rays, but they were in essence, light waves in the ultraviolet spectrum.

Scientists later discovered that ultraviolet light would cause some molecules (called monomers) to chemically bond forming compounds called polymers. This discovery would be particularly beneficial for the curing of inks, coating, and adhesives as it offered a fast drying (non-polluting) technique without the need for solvents and the polluting effects of volatile organic compounds (VOCs).

Spectral output is defined as intensity of light at each wavelength over the range of wavelengths emitted by the lamp. For the most effective cure, this pattern of output must be matched to the pattern of absorption of the photo-initiator in the product. This principle forms the basis of all successful light cure applications. Spectral output determines whether a lamp is suitable for a particular application and how effectively the lamp will cure the product. Basic lamp engineering and modification of the material inside the lamp (called doping) enable shifting of emission maxim to other wavelengths to create different spectral output patterns.

Since there are certain absorption maxims common to many systems, there is often a choice of lamps for a given product. Major absorption areas of importance are 254 nm, responsible for surface cure, 365 nm, the "workhorse" cure wavelength also effective in promoting depth cure, and 400-436 nm in visible spectrum particularly useful for very large depth of cure. Please see the electromagnetic spectrum diagram, figure: A

Lamp intensity is defined as the overall power of the lamp and is most often designated in watts. Also called power density, intensity refers to total lamp output across the entire electromagnetic spectrum. Lamp intensity generally affects rate of cure of particular products, since it is one of the factors determining the amount of light that actually reaches the product.

It is important to distinguish between basic lamp intensity and intensity or amount of light at the working surface. The quantity of light at the working surface is defined in either intensity units or energy units. Light intensity at the product surface, described by the term irradiance, is a measure of momentary exposure and is most often quantified in milliwatts/cm2. Light energy at the surface is a measure of cumulative intensity exposure (intensity x time), quantified as millijoules/cm2, and is simply:

mW/cm2 x seconds = mj/cm2

Measurement of irradiance (light intensity at the working surface) is essential in order to optimize cure conditions and maintain consistency in cure results. Easy to use equipment is available for this measurement.

A mercury vapor lamp consists of six major components: quartz sleeve or body, a gas/chemical mixture, electrodes, seal foil, end caps, and high voltage wires .

The body of the lamp is made from a high quality transparent vitreous quartz tube. Unlike normal glass which blocks ultraviolet radiation, pure quartz has a high transmittance for light in the UV spectrum.

Another important property of quartz is that it can withstand the high temperatures generated under normal operation while exhibiting a low coefficient of expansion. The factors most influencing the length of the body are arc length and curing surface area. Factors most influencing body diameter and wall thickness are operating power.

The gas and chemical mixture sealed within the body consists primarily of argon and mercury. Through research, Albatross UV has found other compounds, when added to the argon/mercury amalgam, aid in extending lamp life and producing a more even illumination along the length of the lamp. Metal halides are also added to the contents of some lamps to increase the spectral intensity of specific wavelengths.

A tungsten electrode is located at the end of each lamp and is used to create the internal arc. The electrodes consist of a tungsten rod with tungsten wire wound around most of its length. Tungsten is used because it has good current handling characteristics, the lowest vapor pressure and coefficient of thermal expansion, and the highest melting point and tensile strength of all the non-alloyed metals.

The lamp requires a good hermetic seal in order to operate. However, glass will not bind directly to the tungsten, so elliptically shaped etched molybdenum foil is used to create the electrical path between the electrodes and the external power source. Molybdenum has the sixth highest melting point of any element and an extremely low thermal expansion making it the perfect choice for a seal foil.

End caps are installed on the end of each lamp to provide the means by which the lamp is physically mounted to the lamp fixture. There are two basic types of end caps: metal and ceramic. Metal end caps are used when the lamp mounting fixture also provides the electrical connection to the lamp. Ceramic end caps are used when power is supplied to the lamp via high voltage wires.

UV lamps generate harmful levels of ultraviolet radiation that can cause serious skin and eye damage through only a short exposure. Extreme care should be taken when working in and around UV equipment. Be careful not to place any part of your body in the direct UV light and do not look directly into a UV light.

UV lamps also emit a narrow band of ultraviolet light that reacts with directly oxygen creating ozone. Ozone has been found to cause headaches, respiratory irritation, and other more serious heath problems. It is very important that all UV curing operations have proper ventilation to prevent the accumulation of ozone. Because of the instability of ozone, it typically quickly converts back into oxygen during the ventilation process.

Line voltage alone is generally insufficient for generating an arc inside the lamp. A step-up transformer is required to develop the higher voltages required. Because mercury vapor lamps are negative resistance devices, they normally require a ballast to prevent them from drawing excessive amounts of current and ultimately destroying themselves.

There are two primary types of reactive ballasts used to operate mercury vapor lamps, inductive and capacitive. With inductive ballasts, the lamp is connected directly to the output of the ballast. These ballasts have two benefits. First, the reactance of the inductor effectively limits the power available to the lamp with only minimal power losses. Secondly, the voltage spike produced by the inductor when power is first applied is often used in some circuits to strike the arc in the lamp. The disadvantage of the inductive-reactance ballast is that current is shifted out of phase with the voltage producing a lower power factor.

Capacitive reactance ballasts overcome this problem by the use of capacitors connected in series with the lamps. These capacitors maintain a constant voltage output to the lamp even when the input voltage varies and is the more efficient of the two.
Ballasts have to be correctly matched to the electrical requirements of the lamps.

There are many factors that influence UV lamp life. How the lamp is operated and the lamp’s operating environment will ultimately determine useful hours of lamp life.
Besides producing UV light, mercury vapor lamps also produce visible light and infrared light. Actually, about 60% of the light produced is in the infrared spectrum. This is because of the high operating temperatures within the lamp. This heat, together with foreign materials deposited on the quartz, causes the quartz to vitrify or decade. This vitrification of the quartz will eventually cause the lamp’s intensity to diminish to a level where it is no longer suited for the application.

How the lamp is operated does influence the speed of vitrification. The quick addition and removal of heat generally increases the speed of vitrification. Therefore, the more times power is cycled on the lamp, the quicker the lamp decays. Starts also have another effect on vitrification. During startup, the lamp’s internal pressure is low. As pressure builds, the electrodes sputter off tungsten, which is deposited on the inside of the lamp and further promotes vitrification. Excessive starts should therefore be avoided by batching your curing operations together.

Another factor influencing vitrification is how the lamp is handled. Any material deposited on the quartz, will cause the quartz to vitrify. This is especially true of the oils on your hands. You should therefore avoid excessive handling of the lamps and always wear clean cotton gloves when replacing lamps. Curing and drying operations also contribute to vitrification as the quartz is exposed to ozone, vapors, hydrocarbons, and volatile gases being emitted from the inks, coatings, or adhesives being cured.

Heat removal is another important factor influencing lamp life. Inadequate cooling and deficient heat removal creates excessively hot operating environments contributing as well to premature vitrification.

Under normal handling and operating conditions, your Albatross UV lamp is guaranteed to provide a minimum of 1000 hours of useful life.

Mercury is considered a hazardous waste and disposal of mercury in the United States must be made in accordance with strict local, state, and federal regulations. Fines and other penalties may be imposed for the improper disposal of mercury lamps. Your local waste authority should be consulted for proper lamp disposal in your area.

National Institute of Standards and Technology (NIST), Atomic Spectra Database.

Text Edition of Large Handbook of Chemistry, Norbert Adolph Lange, Ph.D., and Gordon M. Forker, B.S., Tenth Edition, McGraw-Hill, 1961 (pp. 921-944).

20th Century Inventors: Metal Halide Lamps http://americanhistory.si.edu/lighting/bios/reiling.htm

General lamp history and information: James D. Hooker and Donald L. Klipstein

The Science of Color, the Emission Spectra of the Elements and Some Lamp Engineering Applications

Every component that goes into the manufacture of an Albatross UV lamp is of the very best quality available and produced by leading manufacturers in their respective industries. Because material purity has the greatest effect on our product quality, every effort is made to obtain the purest material and every step in the production process is closely monitored and controlled.

Quartz Tubing

Albatross UV utilizes a high purity, high transmittance, and high temperature fused quartz with low hydroxyl (OH-) content in all of its lamps. This quartz has a nominal purity of 99.995 W% SiO2 making it the ideal sleeve for Albatross UV lamps. High quality quartz tubing is also required because of the extreme temperatures developed inside the lamp. While the internal temperatures (at the electrodes) routinely exceed 2000º C, the surface temperature of the quartz under normal operating conditions ranges from
600º C – 800º C.

Ozone-Free Quartz Tubing

In the production of ozone-free lamps, Albatross UV utilizes a clear fused quartz that has been doped with titanium oxide to block the ozone producing wavelengths. Its visual and dimensional characteristics are identical to the quartz tubing utilized in our standard UV lamps enabling it to radiate the highest levels of UV radiation.

Gases and Chemical Additives

The purity of the gas and chemical additives used in the production process is equally important. Albatross UV only utilizes gases and chemical additives that meet or exceed all industry standards for purity and moisture content. Innovative research and engineering has led to the development of a proprietary gas and chemical composition that not only improves the life of Albatross UV lamps, but also aids in the distribution of mercury in the lamp. This results in a more even light distribution over the length of the lamp.

Tungsten Electrodes

Because they are responsible for creating the high voltage arc necessary for striking the lamp, the electrodes are one of the most important elements in the design of a mercury vapor lamp. The electrodes must be capable of withstanding high voltages, tremendous current, and extraordinary temperatures reaching over 3000º C, while offering reliable lamp starts over the life of the lamp. Our electrodes are constructed out of a specially treated tungsten rod wound with tungsten wire and further processed utilizing an ultra-clean high vacuum furnace at extremely high temperatures to enhance its efficiency and operating characteristics. No other UV lamp manufacturer utilizes the same proprietary process.

Molybdenum Foil

Molybdenum foil is utilized to complete the electrical path between the electrodes in the lamp and the external power supply. Molybdenum foil has several properties that make it an ideal material for this component. The two most important features are that it has a high current rating and very low rate of expansion even at high temperatures.

Albatross UV believes that the total quality of what goes into a lamp determines the total quality of what comes out. Manufacturing a quality lamp requires not only quality materials, but also a quality oriented manufacturing process. While most UV lamp manufacturers are actually fabricating their lamps in overseas factories, we manufacture all of our lamps in the United States. We simply will not sacrifice quality for a lower cost of manufacture.

Accomplished Glass Blowers

The transformation of fused quartz tubes into mercury vapor lamps is made possible by the highly skilled and talented glass blowers employed by Albatross UV. More art than science, glass blowing on a lathe requires a lengthy training period, intense concentration, and thorough familiarity with the thermal characteristics of fused quartz. All of our glass blowers and lathe operators are accomplished artisans and craftsmen.

Glass-working Lathes

Albatross UV lamps are fabricated on specially designed precision lathes that have been engineered to exacting tolerances. In the production of quality lamps, it is critical that the head-stock, tail-stock, and spindle maintain precise alignment. The bearings must have extremely smooth operation and cannot introduce vibration in operation. Air circulation in and around the lathe station must be carefully balanced and controlled in order to remove large amounts of heat and chemical releases while minimizing air drafts in the hot working areas.

Evacuating & Filling

Albatross UV utilizes a proprietary manufacturing process for evacuating the lamp and for introducing the mercury, gas, and chemical mixture into the lamp. This process ensures that all moisture is removed from the lamp prior to filling and the lamp is completely isolated from the environment during filling and sealing operations.

Capping

Albatross UV offers over a wide variety of connectors and wiring configurations to meet all your lamp mounting and electrical requirements. We normally carry a large inventory of ceramic and metal end caps, insulated sleeving, high voltage wire, and an assortment of connectors, lugs, and
wire terminals.

Testing & Quality Control

All of our lamps are individually inspected and thoroughly tested before leaving the factory. Each lamp undergoes a visual inspection to ensure that wires, terminals, end caps, and other components were assembled correctly. After passing the visual inspection, the lamps are then subjected to an electrical test where they are placed under power and evaluated for proper performance. Every Albatross lamp is individually serialized to maintain tractability back to raw materials, production processes, and
manufacturing personnel.

Delivery

Albatross UV carries a large inventory of the most popular lamp styles which are generally shipped within 24 hours of receipt of the order. Orders of less than 20 lamps can normally be shipped within 48 hours. Orders in excess of 100 lamps may take several days to manufacture. We will be happy to work with you to ensure that you get the lamps you need when you need them. So if you have tight deadlines or challenging scheduling requirements give Albatross UV a call and we will do our best to accommodate your situation.

Warranty

We are so confident that our lamps have been manufactured to the highest manufacturing standards that we are willing to offer you this guarantee. If our lamp fails to perform to specifications anytime during the first 1000 hours of normal use, then Albatross UV will replace your lamp at no cost to you.1 No other lamp manufacturer stands behind the quality of their lamps by offering a similar warranty.

Factory-direct pricing

Albatross UV offers factory-direct pricing to all of our customers. Low overhead, a significant investment in state-of-the-art manufacturing and a highly trained, effective, and dedicated staff of personnel enables Albatross UV to offer the very best UV lamp at the very best price.

Technical Assistance

Albatross UV prides itself in providing the best customer service and technical assistance available in the industry. Our customer service representatives are available to answer your technical questions and to help you get the most from your Albatross UV lamps. If you have a requirement for achieving a certain spectral output or in meeting a particular electrical operating parameter, contact Albatross UV today by phone, fax, or email and let us serve you.

World-wide sales and distribution

Albatross UV serves clients and customers world-wide. Albatross UV does business in over 40 different countries and can ship anywhere in the world. We never tack on additional packaging or handling fees and won’t charge you anymore than what Federal Express, United Parcel Service, and the United States Postal Service normally charges for shipping.