Diagnosis and monitoring

Engine Condition Diagnostics and Monitoring

X-ray fluorescence energy dispersive general purpose spectrometer BRA-135F

Analysis of oils in the running engine is performed for its diagnostics for the content of metals. The wear debris occurring in oils may mean the beginning destruction of engine's individual assemblies. Due to their low content the oil is to be filtered and filters are to be analyzed. Example results of such analysis are shown in Table.

Cu	Pb	Sn	Fe	Na	Mg	Ca
15	20	5	48	10	500	2000	Normal
68	71	15	108	10	500	2000	Bearing wear
105	39	10	48	120	500	2000	Internal leaks in the cooling system
200	20	5	48	10	1000	100	Oil additive

All the table data are given in ppm.

Detection of Elements in Greases

X-ray fluorescence energy dispersive general purpose spectrometer BRA-135F

When compared to oils, greases have the following advantages:

low specific consumption;
a simpler design of machines and mechanisms and, therefore, a lower weight, a higher reliability and lifetime;
a longer replacement age;
lower operational costs connected with maintenance.

Greases are complex colloid systems consisting of the following components:

dispersion medium (usually hydrocarbon oils);
dispersed phase – viscosifier (usuallu Ca-, Ba-, Al-based oils);
additive – organic compounds of S, Cl or P;
filler – powders of MoS₂, mica, talcum, BN, bronze, brasses, CuO, ZnO, TiO₂, Cu, Pb, Al, Sn.
the content of the above elements in greases – 1% and more, which allows their direct detection by XSFA method both during formulation control and operation, to check the engine wear.

Nuclear Fuel Production

X-ray fluorescence energy dispersive general purpose spectrometer BRA-135F

Enrichment of uranium fuel for NPP with ²³⁵U isotope is performed through centrifugation of uranium hexafluoride. UF₆ and original metals used for its production shall be checked for possible contamination with chlorine and bromine, which is governed by the standard. The detection limit is from 4 µg/g for chlorine and from 0.2 µg/g for bromine (relative to uranium).

A mixture of uranium and gadolinium oxides in the form of powder and pellets compacted thereof is usually used as nuclear fuel for modern NPP. The uranium oxide content may vary from 98 to 90%, the gadolinium oxide content – from 2 to 10%, respectively. When analyzing using the XSFA method, the internal standard is recommended to enhance accuracy.

The uranium content in non-organic acids is required during uranium fuel production. Both wave dispersive and energy dispersive XSFA may be used for this purpose. The range of detectable uranium concentrations is 2 to 20 g/l. To analyze higher concentrations, the solution needs thinning. The internal standard method is recommended.

Analysis of Industrial Waste

X-ray fluorescence energy dispersive general purpose spectrometer BRA-135FF

The RF Federal law No. 89-ФЗ dated June 24, 1998 defines the legal basis to treat industrial and consumption waste to prevent harmful influence thereof on human health and environment, and to involve such waste into the economic turnover as additional sources of raw materials. Special attention is given to waste containing toxic substances, first of all the following metals: Cd, Hg, Be, As, Sb, Pb, Cr, Co, Ni, Cu and others. The main sources of harmful industrial waste are mining, enrichment, metallurgy, machine-building and chemical enterprises, the main sources of household waste – spent batteries and accumulators (Cd, Ni, Pb) and energy-saving fluorescent tubes (Hg). No doubt that even discussion of possible analysis of unauthorized disposal areas and dumps makes hardly any sense. However energy dispersion XSFA of ore bed overburdens, mill tailings and steelworks slags is quite appropriate. The corresponding methods have already been dealt with in the Geology section (item 1.2.1).

Another current task of XSFA that has already considered in this section is detection of toxic elements in soils, water and air near disposal areas, dumps and enterprises that may be regarded as possible hazard pollution sources.