The development of industrial production，the advanced in Spectroscopy ，make the LED optical instrument (such as the spectroradiometer ) been further improved. But the latter is counteractive at the former, promoted the development of spectroscopy and the development of industrial production. In sixty’s photoelectric direct reading spectrometer developed rapidly as the development of computer technology. Due to the development of computer technology, the development of electronic technology, the miniaturization of electronic computer, the emergence and the popularization of the microprocessor, cost reduction and so on. in the seventy’s of last century spectral instruments almost 100% ground control by the computer, which not only improve the analysis accuracy and speed, but also being automatic controlled to the analysis results of data and the analysis process .After the liberation, China’s spectrum instrument industry developed from scratch, being bigger, get a leap development, and has a certain scale, survived in the competition of the world advanced technology, developed in social commercial competition .1958 China began to trial-produce spectral instruments, and produced it’s first medium quartz spectrograph monochromatic, large spectrograph, monochromatic etc. The Chinese Academy of Sciences Institute began to study and set the optical grating, In1959 Shanghai optical instrument factory, in1963 Beijingoptical instrumentfactory began to study and set the optical grating, in1963,they are succeed in studying lithography grating. from 1966 to 1968, Beijing optical instrument factory and the Shanghai optical instrumentfactory has succeed in developing medium plane grating spectrograph and one meter of plane grating spectrograph and photoelectric direct reading head. From 1971 to1972, domestic first WZG – 200 plane grating spectrometer was manufactured by the Beijing second optical instrumentfactory, open up China’s production history of photoelectric direct reading spectrometer.
Since the 1980s, China foundry industry began introduced of photoelectric direct reading spectrometer as a analyzed means of chemical composition control in the smelting process, and gradually has replaced the traditional wet chemical analysis method, has been developed to be a spectrophotometer method with cooperative to the front analysis that the small and medium-sized enterprise also adopted/used.
The introduction of foreign foundry production line has been equipped with special spectral analysis equipment, as the complete sets of equipment been introduce into China, This is the inevitable result as the casting industry has a strict requirements on the quality control , It is also the merits of photoelectric spectral analysis itself deicide its technique since its inception in 1945,it’s the reason lasted for fifty-six years and enduring’s sake. As everyone knows, the principle of atomic emission spectroscopic analysis is to use the arc (or spark) high temperature Make the sample elements gasification directly from the solid state and be stimulated to emit the characteristic wavelength of each element, Using grating to separate light, Be a “spectrum” arranged by wavelength, These elements‘ characteristic spectral lines through the exit slit, into the respective photomultiplier tube, turn light signal into an electrical signal, Using the apparatus control system to get the electrical signal integrated and been conversed between analog and digital, And then processed by computer, and print out each element percent content. from the above principle of atomic emission spectrometry ， its unique, particularly suited for the front analysis’s advantages can be seen, make it develop into a indispensable analysis means of metal smelting and casting industry , its features are as follows:
- 1. Just polished off the surface oxide of the samples that taking out from the furnace， then the solid samples can be placed on the stage to be excitation, without the trouble of drilling sample from the chemical analysis. For non-ferrous metal samples Like aluminum ，copper and zinc .Can be put the surface oxide skin off by small lathe.
- 2. It just take 20~30 seconds from exciting the samples to the computer to quote out the element analysis content, very fast，it’s useful for Shorten the smelting time and reduce cost. Especially for those elements likely to consumption, it’s more easy to control its final composition.
- 3. All the elements of samples can be analyzed (several or even a dozen) simultaneously analyzed, for complex product, the more cost-effective analysis element, the better its economic benefits.
- 4. The accuracy of Analysis is very high, can effectively control the products of chemical composition, ensured that it can meet the national standard specifications, or even can control the composition of alloy to the lower limit of the specifications, to save the consumption of intermediate alloy or iron alloy.
- 5. The analysis data can be print out from the computer or stocked in a disk, as a permanent record.
In all, to see the photoelectric spectral analysis from the view of technical point, It can said that until now there is no instrument effectively than the front furnace analysis method, and have so many features to replace it. So in the world, smelting, casting and other metal processing companies are competing for the use of this instrument as a routine analysis means, from product quality assurance to economic benefits, it is a very useful analysis tool. Since ninety’s, in China，some well-known enterprises, such as: Changchun FAW, Shanghai Volkswagen, Wuxi Little Swan were introduced foreign foundry production line with Germany OBLF spectrometer as the front analysis equipment. The German company OBLF has thirty year’s history in production spectrometer in Germany; users are all over the world. Instrument type: suitable for a single matrix analysis system for OBLF type GS-1000 (analysis of nitrogen element), set up to 32 channel analysis. Adopted to a variety of matrix analysis system with OBLF QSN-750 (up to a maximum set 60 analysis channels) and type QSG-750 (set up to 60 analysis channels), it can analysis the nitrogen, as well as the acid soluble and acid insoluble aluminum and boron.