AUSTENITIC STAINLESS STEEL WELDING

• Document Type: CREST
• Collection: General CIA Records
• Document Number (FOIA) /ESDN (CREST): CIA-RDP82-00457R005800440011-2
• Release Decision: RIPPUB
• Original Classification: S
• Document Page Count: 2
• Document Creation Date: November 16, 2016
• Document Release Date: February 28, 2000
• Sequence Number: 11
• Publication Date: September 22, 1950
• Content Type: REPORT

S -"A,SSIFCATlv3 t3EGP:. ~',oI S~fian. - u a , O F`ICIA.,,i ONLY 25X1 A
Approved For R~0seL2~`~ v AipkW
ATE REPORT CD NO.
J?S TR' Yt'.gos.
;SUBJECT Austenitie Stainless Steel Welding NO. OF PAGES 2
?LACE
ACQUIRE
25X1A
DATE DISTR.. 22 SFP 50
NO. OF ENCLS.
(LISTED BELOW)
P OF 25X1A
SUPPLEMENT TO
REPORT NO.
1. For the past year the laboratories at Zenica and Jesenice have been working
on the problems involved in manufacturing equipment for the chemical in-
dustry and in repairing turbine assemblies in the Drava and Isonzo power
stations.
In the course of these experiments, the stainless steel produced at
Jesenice knz as Prbkron has proved of great value.. This steel is produced
in two varieties: i9Prokron 11" (Cr - Ni 18/8),, and "Prokron 1916, a high
temperature resisting alloy based on a high percentage of Ni and Cr.
1 okron 19 has already beer, adopted as the standard alloy for the manu-
facture of fine winding wire.
3. In repairing the Kaplan No. 3 turbine at Dravograd, Prokron 11 steel was
used. This steel may be welded either by o y acetylene or electric arc
welders. Because of the lack of nationally produced electrodes, "Boe:hler
Fox Sas 4'" electrodes were employed. The Testing Commission confirmed the
success of the repairs effected, and recommended that the Ministry of
Electric Power approve the repair of all the other turbines in this um nor.
. Engineer Leo Kzez undertook the task of producing an austenitic steel.
electrode capable of being manufactured in Yugoslavia. This electrode con-
sists of a Prokron 19 austenitic steel rod, flux coated, for metallurgical
reasons, with such nationally produced substances as fluoride, chalk, and
ferromengaaiese, instead of acid, As a result of a -special technique per-
mi_tting the most rapid examination of weld slag, it was found possible to
produce a flux giving a stronger and more ductile weld
5. This new nationally produced austenitic electrode, otherwise known as
Prokron Electrode, is now i.n production at Jesenice. it has been laboratory
tested and serves national needs. This electrode will be used, together
with Boehler Fox Sas 4 and Swedish electr-ades, in repairing the Kaplan No. 2
turbine at Dravograd
The characteristics of the electrode used to weld Prokron steel are
a{. s'rokron 19 rod composed' of z
C 0.15 -- 0.25 percent
CLASSIFICATION
S-rATE -6- i iiAvy SRI3 ~
I Document
Cis:3ro
Approved For Release 2000/05/18 : CIA-R
s s c
19;5800440011-2
ZB--- N? -28----
 Approved For Release 2000/05/18 : CIA-RDP82-00457R005800440011-2
SEC/CONTROL - U.S. OFFICIALS ONLY
CENTRAL INTEI.LIGENCE AGENCY
Mn Approximately 0~5 percent
Si Approximately OR5 percent
Or 24 - 26 percent
Ni 20 ? 21 percent
25X1A
b0 Flux coating containing experimentally determined quantities of
fluoride, chalk, ferromanganese, and water glass,
7. The new electrode, in common with Prokron steel, has, however, one defect
3.t is susceptible to intercrystalline corrosion. In order to overcome.
this, stainless steel intended for welding must include molybedium, as
well as titanium (in proportion of 5 x carbon content), or Ni Cb (in
proportion of 10 x carbon content), or tantalum. With the addition of
these alloys, Prokron steel will be able to remain stable under welding
Further, the addition of these alloys does not affect the technique of
welding or fluxing since their stabilizing effect operates after and not
during welding?
8. math.. a view to solving the problem outlined above, the following proposal
was made: modern welding tecinique requires a stainless steel proof
against intercrystalline corrosion and the effects of slow cooling after
y gelding, >Iith these advantages, the composition of Prdcron 11 should
consist of:
C bare minimun, max,
0,10 percent
Si Approximately.
0.5
percent
Mn 0.5
1,0
percent
Cr 17
18
percent
Ni 8
3
percent
Mo 2
3
percent
Nb plus Ta
I
percent
Ti 1
S plus P bare minimtun
1.5 percent
These special additions are also proposed for Prokron 19,, with the
difference that the carbon content is less,
SENT/CONTROL - U.S. OFFICIALS ONLY
Approved For Release 2000/05/18 : CIA-RDP82-00457R005800440011-2