TERMINOLOGY IN CRYOGENIC ENGINEERING

I. P . V i shnev , M. E . Lebedev , and A. I . Moroz

UDC 621.56.001.4

Rapid development of low temperature physics and engineering during the past few years has resulted in the appearance of new concepts, measurements , and te rms in scientif ic-engineering publications. How- ever, they are often ambigious about the real significance of the measured variable and are inconsistent among themselves as well as with existing te rms in allied fields.

A conference of scientists and representat ives of a number of f i rms and institutes f rom the United 9 Kingdom, France, German Federal Republic, USA, Netherlands, Switzerland, and the International Cold Institute (ICI) was held in Par i s in December 1969. The problem of defining terminology in low temperature physics and engineering was discussed.* The conference cited the inconsistency of a number of te rms in the cryogenic engineering field and recommended a wide-ranging discussion by low temperature special ists of certain terms proposed by the conference. These special ists should prepare recommendations for final consideration by delegates f rom member countries of the ICI.

This art ic le presents proposals for certain basic te rms of low temperature engineering.

9 Temperature Regions and Ranges. It is recommended to call temperatures below 120~ cryogenic temperatures . This will result in a sharper division between the moderate ly cold region and the region of intense cold with an upper l imit of 120~

*N. Kurti, Cryogenies,

9 ~ ~,~

0 o

~, ~o..~ - ZOO

~o_~_~ i

~o - ZO

9 ~ - 15

" i - lOi

~.! - 31

zl

0,0i

~I

10, No. 3 (1970).

~--273.16(Lp. ofHzO) Z?J,/5 [ [ l

120 - - -

-1.54,8 (cr. p. of Of) -_. 126.25 (cr. p. of N~ )

i- 00.18 (b.p. of 02)

.63.15(r.. F of N 2) -eg.3~(t.p. of Oz)~ .~

".-44-4(cr. 1~ ofNe) i .~

:~ $3,O(ct.p. of Hz) i- 2'/.1 (b. p. of Ne) - 20.3 (b. p. o fH2)

- 13.81(r. ~ ofHz ) .~

o~o - 5,2(cr. p, of He) 0

=- 2.17 (X-p. of He)~

?iTS- o

I -

d 2 _

,0-,. I

~;_

!

~_ I I J I

Fig. 1. Low temperature scale: c r .p . ) cr i t ical point, b.p. ) boiling point at 1.013 9 105 Paseals absolute pressure , t.p.) tr iple point, and k-p.) lambda- point.

Translated f rom Khimicheskoe i Neftyanoe Mashinostroenie, No. 6, pp. 38-40, June, 1972.

9 197J Consultants Bureau, a division of Plenum Publishing Corporation, 227 West 17th Street, New York, N. Y. 10011. All rights reserved. This article cannot be reproduced [or any purpose whatsoever without permission of the publisher. A copy o[ this article is available [rom the publisher for $15.00.

576