Vol 93, No 12 (2004)

The new head office of Bitzer Kiihimaschinenbau GmbH in Roggenburg, Germany, for the production of screw compressors was put into operation at the end of 2003. With a capacity of more than 25,000 compressors per year, this plant has become one of the largest enterprises in the world producing screw compressors for air conditioning and refrigeration systems. The preconditions for the construction of the new plant and the transfer of all production capacities from the old plant in Sindelfingen were the significant expansion of Bitzer over the past years and, in particular, the success of screw compressors. The annual increase in their output was more than 35%, and the old production was bursting at the seams! At the same time, the output of reciprocating compressors also increased significantly. Their production in Europe was completely transferred to the factories of the cities of Schkeuditz (Germany) and Castelo Branco (Portugal). This decision made possible the material and technical separation of the two production technologies, which had a positive effect on the total activity and costs of the companies. In addition to the named European enterprises, Bitzer compressors are manufactured according to around the world. Factories in Brazil and China produce a range of compressors to meet the needs of the local refrigeration and air conditioning markets.

A pressure-enthalpy diagram for the real refrigerant R134a / Castrol Icematic SW22 has been developed.

The influence of the oil impuriries on configuration of main isolines in the diagram was considered. The role of use of the offered diagram in theoretical evaluation of the efficiency of refrigerating equipment is highlighted.

The Frigodesign firm positions itself in the refrigeration market as an engineering company that performs for a specific customer a cycle of work on the calculation, selection and manufacture of complex non-standard or unique refrigeration equipment.
Among the completed orders: Cascade plant for cooling continuous steel strip from +30 to -70 °C in the hardening chamber for thin-walled sheet metal; Climatic chamber with a volume of 42 m3 with controlled temperature, humidity and air speed, accepted by the Rostest certification center; S multi-compressor two-stage plants for freeze-drying of pharmaceuticals at -70 °C and a number of other equally interesting objects. This article discusses equipment manufactured by Frigodesign for cooling liquids.

This year there are two anniversaries associated with Pyotr Leonidovich Kapitsa. They are important for many - not only for physicists and engineers, but also for all those who are interested in the history of our country. P.L. Kapitsa not only made a significant contribution to Russian science, but also left a bright mark on the history of the political and economic life of our country.

Class H filters (HEPA type-High Efficiency Paticle Air) with an efficiency of removing microorganisms and inert aerosol particles of 0.3 microns in size of 99.97% or more are used in “clean” rooms of cleanliness classes (ISO 5-ISO 7). Class U ultra-high purification filters (ULPA type-Ultra Low Penetration Air) with an efficiency of removing particles with a diameter of 0.1-0.2 microns of about 99.999%-in “clean” rooms of ISO 1-SO 4 classes. In rooms of ISO 8 class (class 100 000) the use of absolute filters is not practical. It is recommended to use pocket filters with a 0.5 µm particle removal efficiency of about 90%.