Kuppan T. Heat Exchanger Design Handbook
Подождите немного. Документ загружается.
654
Chapter
I2
Pitting Corrosion
Susceptible materials include aluminum, stainless steels, and copper alloys. Pitting corrosion
takes place on the tube sheet and tube wall in the form of pits after local destruction of the
protective film by deleterious chemical species such as chlorine or mercury ions. Additionally,
at water speeds below about 3 ftjs, suspended solids tend to settle on the tube and may initiate
pitting corrosion under the deposits due to differential cell action
[
1041.
Causes for pitting
on
the tube side include the following [32]:
Nonhomogeneous tube surface
Irregular sludge deposition from the water
Local concentration of salt during standstill
Putrescent products with
H2S
Dry-out
of
protective layer followed by peeling off
Small metallic inclusions like oxides, and sulfides
Foreign matter, such as sand, oil, barnacles, etc.
Most of these potential causes of pitting corrosion can be avoided by tube cleaning or removing
chloride ions and others involving the water chemistry; use steel containing
MO.
Crevice Corrosion
Crevice corrosion takes place in the area between the tube and the tube sheet, at gasketed joints,
beneath deposits, and at bolt holes. Proper tube expanding will prevent the circumferential tube
crack
in
tube-to-tube-sheet joints. While pitting and crevice corrosion normally occur fairly
uniformly throughout the heat exchanger, the attack may predominate
on
the bottom of the
internal surfaces of the tubes if mud or sediment has collected there and promotes crevice
corrosion
[
261.
Stress Corrosion Cracking
Most common metals and alloys are susceptible to SCC. This form of corrosion takes place at
the tube-to-tube-sheet expanded joints, and at U-tube bends.
Corrosion Fatigue and Fretting Wear
All
alloys, at the tube and baffle interface,
and
tubes at midspan due to collision between
adjacent tubes are susceptible to corrosion fatigue and fretting wear.
Erosion of Tube Inlet
When the cooling water contains large quantities of suspended abrasive solid particles, any
protective film formed is rapidly removed and the tube is liable to thin
[104].
The most com-
mon tube failures due to erosion-corrosion from impingement attack are discussed
in
the sec-
tion on erosion-corrosion. The problem
of
inlet-end tube erosion (erosion-corrosion)
in
high-
pressure feedheaters with carbon steel tubes and condensers with copper alloy tubes is dis-
cussed here. In general, the factors governing erosion-corrosion
in
feedwater heaters are
[
1071:
Feedwater velocity (turbulence)
pH value of feedwater (protective layer of
FETO,)
0:
content of feedwater (corrosion)
Feedwater temperature (protective layer)
It has been suggested that at the usual pH values
(9-9.5)
and
O2
contents (0.002-0.007 ppm)
and with water chambers and tube inlets designed to promote uniform water flow, erosion at
the tubes and tube inlets can be eliminated, even for high water velocity
[
1071.
Corrosion
655
Dezinci fication
Tubes and tube sheets made of brasses are susceptible to dezincification.
Microbiologically Induced Corrosion
All but the higher nickel-chromium alloys and titanium have been found to be subject to
microbiological corrosion. This form of failure was discussed earlier.
6.8
Material Selection for Condenser Tubes
The following main physical and chemical parameters revealed by water analysis are used to
select the tube materials
[
1051: total dissolved solids (TDS), total suspended solids, sand con-
tent, chloride content, sulfur and
NH3
content, and biochemical oxygen demand. The selection
of materials for cooling water applications based on flow velocity and total dissolved solids is
shown in Fig. 41.
6.9
Operational Maintenance of Condensers and Feedwater
Heaters
Important corrosion control measures for the maintenance of condensers and feedwater heaters
include the following
[
1081:
1.
The tubesheets are clad with stainless steel.
2.
All water boxes are fitted with sacrificial anodes.
3.
Depending on the water quality, ferrous sulfate is dosed.
656
Chapter
12
4.
Upstream filtration ensures clean filtered water in association with an online cleaning
system using sponge rubber balls to permit continuous cleaning of the tubes.
5.
Excessive biological growth is controlled with chlorine.
6.
Operation and shutdown based on many years of experience ensure correct treatment of
the heat exchangers.
7
MATERIAL SELECTION FOR HYDROGEN SULFIDE
ENVIRONMENTS
Degradation of steel by hydrogen sulfide (H2S) is now recognized as a serious problem
in
pipelines handling sour crude oil or gas in petroleum refinery equipment. Sour environments
are defined as fluids containing water as a liquid and hydrogen sulfide. Hydrogen sulfide
resistance steels for pressure vessels or pipelines in sour environments are often required
to
have both resistance to H2S cracking and low-temperature toughness. Because iron-base alloys
are principal materials of construction, these alloys have been the focus of study for many
years. An important reference on hydrogen effects on steels is Warren
[
1091.
7.1
Effects
of
Hydrogen in Steel
Hydrogen sulfide below dewpoint forms complex sulfides on metallic surfaces. Monoatomic
hydrogen can then diffuse into the material and recombine to form molecular hydrogen at
voids, laminations, microcracks, or discontinuities around inclusions, generating extremely
high pressures
[
1091.
As
an interstitial element in the body-centered cubic (bcc) ferrite lattice,
hydrogen can cause a number of mechanical problems for steels. It gives rise to blistering and
cracking. It stiffens the metal, impairing its ductility. Spontaneous cracking of materials is
possible
if
the material hardness is not limited. The effect of hydrogen absorbed by carbon
steels is well known and extensively reported in the literature. The primary effects are:
1. Hydrogen-induced cracking (HIC) producing stepwise cracks to the metal surface.
2.
Hydrogen embrittlement (HE) due to loss of ductility under a slow tensile loading.
3.
Cracking in high-strength or high-hardness steels, known as hydrogen sulfide stress crack-
ing (HSCC) or sulfide stress corrosion cracking (SSCC).
4.
Blister formation originating at nonmetallic inclusions, known as hydrogen blistering.
Figure
42
shows the effects of hydrogen on steel except hydrogen embrittlement. Requirements
for the manufacture of pressure vessels for wet H2S source is discussed in WRC Bulletin
374
[
1101.
7.2
Sources
of
Hydrogen in Steel
Hydrogen embrittlement and other phenomena influenced by hydrogen require a susceptible
material and a fabrication method or process capable of promoting the entry of hydrogen into
the steel. Before hydrogen can enter a metal, it must first adsorb on the metal surface as atomic
hydrogen. Nascent or newly created atomic hydrogen can result from various operational
pro-
cesses
[
109
]:
initial melting, electroplating, acid pickling, high-pressure hydrogen environment,
decomposition of gases (e.g., ammonia), hydrogen pickup during welding, corrosion with ca-
thodic liberation
of
hydrogen, and hydrogen from cathodic protection. Acid corrosion, particu-
larly in the presence of a “poison” such as sulfide, cyanide, arsenic, selenium, or antimony
ions, promotes the entry of the hydrogen into the steel [3]. The nascent atomic hydrogen
(H”)
charged into the steel as a by-product of the corrosion reaction rather than gas evolution as
H,
is shown by the following equation
[
1091:
Corrosion
657
r
I
1
I
a
C
b
d
Figure
42
Schematic views
of
cracks. (a) Blister;
(b)
HIC; (c) SSCC in low tensile strength steel;
and (d) SSCC in high tensile strength steel.
(From
Refs.
110
and
11
1.)
Fe"
+
Fe'+ +2e
2H'+ 2e
+
2H0
7.3
Hydrogen-Induced Cracking
Some of the atomic hydrogen evolved by the corrosion reaction diffuses into the steel and
forms molecular hydrogen, which accumulates at discontinuities, principally inclusion metal
interfaces
[
1 1
13.
When the internal pressure due to the molecular hydrogen buildup exceeds a
critical level, hydrogen-induced cracking (HIC) is initiated. It is recognized that HIC can occur
in sour environments in the absence of external stress. Cracking can proceed along segregated
bands containing lower temperature transformation products such as bainite and martensite.
Cracking tends to be parallel to the surface but can be straight or stepwise.
Stress-Oriented Hydrogen-Induced Cracking
When the small hydrogen-induced cracks or stepwise cracks coalesce perpendicular to the
axis of
an
applied tensile stress on a relatively low-hardness steel having a ferrite-pearlite
microstructure, the phenomenon
is
known as stress-oriented hydrogen-induced cracking
(SOHIC)
[
1121. It occurs around weldments (Fig. 43) in fabricated steel vessels and process
equipment
[
1131. According to Kane et al. [113], the combination of stress concentration,
residual tensile stress, hardness, and microstructure makes these locations prone to SOHIC.
Susceptibility of Steels to HIC
Metallurgy
of
Steels.
The susceptibility
of
steels to cracking is influenced strongly by inho-
mogeneities such
as
the nonmetallic inclusions, their shape and distribution, and segregation
-
-
658
Chapter
12
Notch effect
c
SSC
in
HAZ
-
w
-
-
-
WeId/H
I
C
interact
ion
c
c
-
-5
-
c---
-
HIC/HIC
interaction
Figure
43
Schematic
of
SOHIC formation in carbon steel weldment
[
1
131.
of alloying elements
[
1
1
11.
Voids, MnS stingers, oxide inclusions, and laminations present in
the steels act as nucleation sites for blistering, stepwise cracking, and SOHIC [112].
Eniirunmental
Factors. Environmental factors such as H2S partial pressure, pH of the solu-
tions, and other phenomena relevant to the absorption of hydrogen by the steel influence
HIC
[lll).
Strength and
Alloying
Elements.
The risk
of
cracking is increased by increasing the strength
of steel
as
well as the partial pressure of H2S.
Microstructz4re.
In
general a nonhomogeneous microstructure such as pearlite banding can
give high susceptibility to hydrogen embrittlement.
Prevention of HIC
Steels with resistance to HIC embody the following features:
1.
The effects of segregation can be minimized by restricting the levels
of
elements such as
C,
S,
Mn, and
P
and controlled rolling of plates, which enables high strengths to be
obtained at low carbon levels. For wet H2S systems, there are recommendations to use
low-sulfur steels that have been qualified for HIC and SOHIC resistance using laboratory
testing. The sulfur content is generally reduced to below 0.01%.
2.
Addition
of
calcium or rare earth metals to globularize the sulfide inclusions.
3.
Low
levels
of
oxide inclusions.
4.
Mn
is
beneficial
in
improving toughness by refining the ferrite grain size, and therefore a
minimum level of Mn must be maintained. Long elongated inclusions such as type
I1
MnS
are particularly favorable sites for crack initiation. Spheroidal inclusions are less suscepti-
ble to crack initiation except when they are in clusters
[
1 111.
5.
Freedom from segregation
so
as
to avoid bainitic or martensitic bands.
6.
Reduced corrosion effects.
7.
Periodic inspection of the wet
H2S
refinery equipment even if it is made from HIC-resistant
steel, as these steels may not provide total resistance to HIC and SOHIC in actual refinery
service
[
1
131.
Corrosion
659
8.
Use of stainless steel and stainless steel clad material for severe wet H2S service as an
alternative to reduce inspection and reinspection requirements. Clad products can be used
for repair, replacement, or new construction
[
1
131.
7.4
Hydrogen Embrittlement
Mechanism of Hydrogen Embrittlement
Hydrogen embrittlement involves two issues: (1) The crack has been formed by hydrogen, and
(2) the toughness changes because the material has been embrittled. Atomic hydrogen dissolved
in steel can interfere with the normal process of plastic deformation. If a steel of initially
limited notch ductility (e.g., a steel hardened to 175,000 psi) is charged with atomic hydrogen
and strained at the appropriate rate and temperature, it cannot plastically deform to locally
accommodate a notch or stress raiser. Consequently, a crack is initiated and brittle fracture can
take place. Severely cold-worked ferritic steels and as welded steels of higher carbon content
are similarly vulnerable
[
1091. Plain carbon or alloy steels heat-treated to tensile strengths
greater than 120,000 psi
or
hardness >Rc 22-23 are susceptible to hydrogen embrittlement.
However, the other forms of hydrogen damage such as hydrogen attack or hydrogen blistering
are associated with unhardened low-alloy or carbon steel
[
1
141. The susceptibility of steels to
hydrogen embrittlement increases with
[
1091:
1.
Increasing strength level (hardness) of the steel
2.
Increasing amounts of cold work (plastic deformation)
3.
Increasing residual or applied stress
The risk of cracking initiation should be reduced by avoiding notch effects, whether geometri-
cal or “metallurgical.” Metallurgical notches include the formation of hard zones
in
the parent
metal and
in
the weld areas. Crack propagation can be controlled by limiting operating andor
residual stresses and also by postweld heat treatment.
Hydrogen Embrittlement of Steel Weldments
Susceptible Steels.
Steels with weldments susceptible to hydrogen embrittlement include
pressure vessel quality steels with
0.25-0.35%
C, in plate thickness 1-2 in
(25.4-50.8
mm),
such as ASTM A515 and
A516
[109].
Prevention
of
Hydrogen Embrittlement and Cracking
of
Welds.
Welding-related measures for
prevention of hydrogen cracking, such as use
of
dry electrode, joint surface cleanliness, suffi-
cient preheat, and postweld heat treatment, will be helpful to prevent hydrogen embrittlement
of welds. Hardness testing of weldments is a necessary requirement for most typical operating
refinery or chemical plant environments. Limiting the weld hardness of carbon and low-alloy
steels as indicated in NACE Standard MR-01-75 [115] can generally avoid this problem. Hard-
ness of completed P-1 welds should be
200
BHN or less.
7.5
Hydrogen-Assisted Cracking
Hydrogen-assisted cracking (HAC), also known as hydrogen sulfide stress corrosion cracking
(HSCC), is a special case of localized hydrogen embrittlement where the nascent atomic hydro-
gen is supplied to the steel as a by-product of the corrosion reaction. Acid corrosion of steel
in the presence of a “poison” such as sulfide, cyanide, arsenic, antimony, or selenide ions is a
prime example [109]. Examples for HSCC include sulfide stress cracking and cyanide stress
cracking of hardened steel.
660
Chapter
I2
Prevention of HSCC
HSCC can be controlled or prevented by
(1)
selecting a material that is resistant to process
corrosion, and (2) avoiding the formation of hard and brittle microstructures. These two aspects
are discussed next.
Material Selection.
HSCC can be controlled or prevented by selecting a material that
is
resis-
tant to process corrosion; that is,
if
there is no corrosive attack on the material, there can be
no cathodic liberation of hydrogen and, hence, no localized hydrogen embrittlement.
Avoiding the Formation
of
Hard and Brittle Microstructures.
HSCC poses problems in weld
zones. It can occur especially in heat-affected zones with high hardness
[
1 1 I]. Attention should
be given to composition, hardenability, and welding procedures to avoid the formation of hard
and brittle microstructures. The occurrence of HSCC observed typically in high-strength steels
having yield strength higher than
90,000
psi (620 MPa) is currently mitigated by imposing a
restriction of maximum hardness of 22 Rc or 225-235 BHN. Nevertheless, countermeasures
similar to those described for the prevention of HIC are necessary to prevent HSCC
in
HA2
even with relatively low hardness
[
11
11.
7.6
Hydrogen Blistering
Hydrogen blistering is a mechanism that involves hydrogen damage of unhardened steels near
ambient temperature
[
1
141. The blister originates at nonmetallic inclusion or other internal
defects such as voids, laminations, or microcracks. Blistering requires a vulnerable material
and a fabrication method or process condition that promotes the entry of atomic hydrogen into
the steel as a by-product of the corrosion reaction rather than gas evolution as H2.
Susceptible Materials
Blistering is usually confined to the lower strength grades of steel, with tensile strength
70,000-
80,000
psi, and Rc
22
or less hardness, rimmed or semikilled steels because of laminations,
and free machining steels with extensive sulfide or selenide stringers that can serve as blister
sites.
Prevention
of
Blistering
Some of measures suggested by Warren [109] for prevention of blistering include the
fol-
lowing:
I-
-I
W
Figure
44
Determining hydrogen induced cracking (HIC) resistance
(NACE
specification TM-02-
96).
Test specimen and crack dimensions
to
be used in calculating: crack sensitivity ratio
(CSR)=
Ca Cb
(a
b,
x
100%;
crack length ratio (CLR)
=
-
x
100%;
crack thickness ratio
(CTR)
=
-
x
100%
(W
X
T)
W
T
where a
=
crack length; b
=
crack thickness; W
=
section width; and
T
=
test specimen thickness. Note:
in the past CSR has been calculated by some investigators as (Ca
x
Cb)/(W
x
T),
which is simply the
product
of
CLR
x
CTR (i.e.,
Za/W
x
Zb/T). This does not give the same value as
C
(a
x
b)/(W
x
T).
Corrosion
661
1,
Selection of steel: (a) Where blistering is a concern, calcium-treated and argon-blown
steels with 0.010%
S
maximum offer optimum resistance, (b) steels fully killed by silicon
additions are preferable to aluminum-killed steel, (c) avoid susceptible steels such as
rimmed, semikilled, and free machining steels, (d) hot-rolled or annealed material is prefer-
able to cold-rolled material, and (e) apply cladding, lining, or protective coating with
a
more corrosion-resistant material.
2.
Quality control and inspection of steel: To minimize blistering at planar defects, such as
laminations and inclusion aggregates, steel plate should be ultrasonically inspected as per
ASTM standards
El 14
and
A578.
3.
Venting of multilayer vessels.
Detection of Blisters in Service
Surface blisters may be detected by
(1)
visual inspection or by hand touch, (2) wet fluorescent
magnetic particle inspection,
(3)
ultrasonic inspection to detect internal blisters within the steel,
and
(4)
acoustic emission testing for locating active sites of SSC, HIC, and SOHIC
[
1131.
Inspect both internal and external surfaces, including the less obvious items such as repair
patch plate and unvented attachments (e.g., lifting lugs and support legs).
Correction of Blistered Condition in Steel Equipment
If blisters have jeopardized the vessel integrity, cut out the blistered areas and replace with
ultrasonically inspected plate. Vent the blisters by careful drilling from the outside
of
the
vessel. Avoid ignition of hydrogen within the blister; do not torch cut
[109].
7.7
Pressure Vessel Steels for Sour Environments
Plates for Pressure Vessels in sour gas service are normally constructed of low-carbon steel
ASME SA
516-70
normalized to ASTM Specification
A300.
7.8
HIC
Testing Specification
HIC testing is performed according to NACE TM-02-96
[
1
161.
Refer to Fig.
44
for the various
parameters evaluated by this test method. Testing frequency by the manufacturer is one plate
of each thickness rolled from each heat
of
steel. Melting practices by Lukens, one
of
the
leading manufacturers of A
5
16-70,
are mentioned here
[
1
171.
All "HIC-Tested A
5
16"
steels
are produced to the Lukens Fineline Double-0 Two or more restrictive requirements, which
utilize various maximum sulfur levels and calcium treatment for inclusion shape control. Phos-
phorus and oxygen level maximums may also
be
accepted. Two classes of chemistry control
and HIC test guarantee levels may be specified for crack length ratio (CLR), crack thickness
ratio (CTR), and crack sensitivity ratio (CSR).
REFERENCES
1.
Munger,
G.
C., Corrosion as Related to Coatings, in
Corrosion Prevention by Protective Coatings,
National Association of Corrosion Engineers, Houston,
TX,
1984, Chapter
2.
2.
Uhlig,
H.
H.,
Environmental effects
on
properties
of
materials,
Mater. Protect. Perjiorm.,
July,
23-27 (1972).
3.
Resistance
to
Corrosion, Inco Alloys International,
WV,
4th ed., 1985.
4.
Jarman,
R.
A., and Shreir,
L.
L.,
The basic principles of corrosion,
Welding
&
Metal Fabrication,
October, 370-379 (1987).
5.
Corrosion Tests and Standards-Application and Interpretation, ed., R. Baboian, ASTM, Philadel-
phia,
1995.
662
Chapter
I2
6.
Brosilow, R., Can you weld to avoid corrosion,
Welding Design
&
Fabrication,
September, 67-74
(
1982).
7.
Roser, W. R., and Rizzo, F. E., The corrosion engineer's look at passive alloys,
Mater.
Protect.
Perform.,
April, 51-54 (1973).
8.
Silverstein, M. R., Cooling,
Chem. Eng.,
August 9, 84-94 (1971).
9.
Fontana, M.
G.,
and Greene, N. D.,
Corrosion Engineering,
2nd ed., McGraw-Hill, New York,
1978.
10.
Craig,
B.,
Introduction,
in
Metals Handbook,
vol. 13,
Corrosion,
9th ed., American Society
for
Metals, OH, 19XX, p. 79.
11.
Atmospheric corrosion, in
Corrosion Basics-An Introduction,
NACE, Houston, TX, 1984.
12.
Merrick,
R.
D., Design
of
pressure vessels and tanks to minimize corrosion,
NACE,
Materials
Performance,
January 1987, pp. 29-37.
13.
AL-6XNR Alloy, Allegheny Ludlum Allegheny Ludlum Steel Corporation, Pittsburgh, PA.
14.
Kobrin,
G.,
Materials selection, in
Metals Handbook,
Vol. 13,
Corrosion,
9th ed., American
Soci-
ety for Metals,
OH,
19XX, pp. 321-337.
15.
Elliott, P., Design details to minimize corrosion,
in
Metals Handbook,
Vol. 13,
Corrosiarz,
9th ed.,
American Society for Metals, OH, 19XX, pp. 338-343.
16.
Freedman, A. J., and Boies,
D.
B., Causes and cures for cooling water corrosion problems,
Prtro-
leum Rejher,
April, 157-162 (1961).
17.
Stanfield, B. M., Polarization cell:
A
common cure for corrosion,
Mater.
Protect. Perform.,
March,
32-35 (1973).
18.
Steven, P. L., General corrosion,
in
Metals Handbook,
Vol. 13,
Corrosion,
9th ed., American
Society for Metals,
OH,
19XX, pp. 80-103.
19.
Open pitting corrosion, in
Corrosion Basics-An Introduction,
NACE, Houston, TX, 1984.
20.
Corrosion
in
Power Generating Equipment
(M.
0.
Speidel and
A.
Atrens, eds.), Plenum Press,
New York, 19XX.
21.
Lichtenstein, J., Fundamentals of corrosion causes and mitigation,
NACE, Materials Performance,
Mach, 29-31 (1978).
22.
Wilten, H. M., Microscope speeds diagnosis of refinery corrosion,
Hydrocarbon Processing
&
Petroleum Refiner,
40(
lO), 15 1-280 (1961).
23.
Asphahani,
I.
A., Corrosion resistance of high performance alloys,
Mater.
Perform.,
19(
12),
33-43
(1980).
24.
Uhlig, H. H., Discussion-An essay on pitting, crevice corrosion, and related potentials,
Discus-
sion, Materials Performance,
August 1983, pp. 35-36.
25.
Dexter,
C.
S.,
Localized corrosion, in
Metals Handbook,
Vol. 13,
Corrosion,
9th ed., American
Society for Metals,
OH,
19XX, pp. 104-122.
26.
Syrett,
B.
C.,
and Coit, R.
L.,
Causes and prevention of power plant condenser tube failures,
NACE, Materials Performance,
February, 4449 (1983).
27.
Jarman, R. A., and Shreir, L.
L.,
Corrosion of jointed structures-Part
11,
Welding
&
Metal
Fahri-
cation,
NovemberDecember, 445-449
(
1987).
28.
Henthorne, M., Understanding corrosion,
Chem. Eng.,
Desk Book Issue, December
4,
19-33
(1972).
29.
Guide to selecting engineered materials, metals polymers ceramics composites,
Advanced Matcri-
als
&
Processes,
137(6), (1990).
30.
Stengerwald, R., Metallurgically influenced corrosion,
in
Metals Handbook,
Vol.
13,
Corrosion,
9th ed., American Society for Metals,
OH,
19XX, pp. 123-135.
31.
Condenser Tube Handbook,
Bridgeport Brass Company, UK.
32.
Forchhammer, P., Results of damage research on corrosion failures
in
heat exchangers,
Heat
Transfer Eng.,
5(3-4), 19-32 (1984).
33.
Woodward, A. R., Howard, D.
L.,
and Andrews,
E.
F. C., Condensers, pumps and cooling water
plant, in
Modern Power Station Practice,
Vol. C,
Turbines, Generators, and Associated Plant
(D.
J. Littler,
E.
J. Davies, H. E. Johnson, F. Kirkby, P. B. Myerscouh, and
W.
Wright, eds.), Pergamon
Press, New York, 19XX, Chapter 4.
Co
rrosion
663
34.
Crook, P., Practical guide to wear for corrosion engineers,
Mater. Perform.,
February,
64-66
(1991).
35.
Erosion-corrosion, in
Corrosion Basics-An Introduction,
NACE, Houston, TX,
1984.
36.
Yokell,
S., A Working Guide to Shell and Tube Heat Exchangers,
McGraw-Hill, New York,
1990.
37.
Standards of Tubular Exchanger Manufacturers Association, 7th ed., Tubular Exchanger Manufac-
turers Association, Inc., Tarrytown, NY,
1988.
38.
Cavitation, in
Corrosion Basics-An Introduction,
NACE, Houston,
TX,
1984.
39.
Dawson, J. L., Shih, C. C., Gearey, D., and Miller, R. G., Flow effects of erosion<orrosion,
Mater. Pegorm.,
April,
57-60 (1991).
40.
Dawson,
J.
L.,
and Shigh, Corrosion Under Flowing Conditions-An Overview and Model,
COR-
ROSION/90,
Paper No.
21,
Houston,
TX,
1990.
41.
Syrett, B. C., Corrosion in fossil fuel power plants, in
Metals Handbook,
Vol.
13,
Corrosion,
9th
ed., American Society for Metals, OH,
19XX,
pp.
985-1010.
42.
Theus, G. J., and Daniel, P.
L.,
Corrosion in steam generating systems, in
Corrosion
in
Power
Generating Equipment
(M.
0.
Speidel and A. Atrens, eds.), Plenum Press, New York,
19XX,
pp.
185-23
1.
43.
M/s. Expando Seal Tools, Inc., Montgomeryville, PA.
44.
Irving, B., Stress corrosion cracking: Welding’s no.
1
nemesis,
Welding
J.,
December,
37-40
(1992).
45.
Kedzie, D.
P.,
and Rizzo, F. E., The corrosion engineer’s look at stress corrosion,
Mater. Protect.
Perform.,
October,
53-56 (1972).
46.
Logan, H. L.,
The Stress Corrosion Cracking
of
Metals,
John Wiley, Inc., New York,
19XX.
47.
McIntyre, D.
R.,
and Dillon, C. P., Guidelines for Preventing Stress Corrosion Cracking in the
Chemical Process Industries, Publication
15,
Materials Technology Institute,
1985,
pp.
8-14.
48.
Berry, W. E., Stress Corrosion Cracking-A Nontechnical Introduction to the Problem, Defense
Metals Information Centre, Battell Memorial Institute, Columbus, OH, DMIC Report
144,
January
6, 1961.
49.
Pement, F. W., Wilson,
I.
L.
W., Reynolds,
S.
D.,
and Fletcher, W. D., Microanalytical character-
ization of stress corrosion cracking in power plant heat exchanger tubing,
Mater. Perform.,
pp.
26-39 (1977).
50.
Craig, B., Environmentally induced cracking, in
Metals Handbook,
Vol.
13,
Corrosion,
9th ed.,
American Society for Metals, OH,
19XX,
pp.
145-149.
51.
Brown,
B.
F.,
Stress Corrosion Cracking in High Strength Steels and in Titanium and Aluminum
Alloys, Naval Research Laboratory, Washington, DC,
1972.
52.
Parkins, R. N., and Foroulis,
Z.
A., Stress corrosion cracking of mild steel in monoethanolamine
solutions,
NACE, Materials PerJormunce,
January,
19-29 (1988).
53.
Thompson, D. H., How to prevent stress-corrosion cracking of copper alloys,
Chem.
Eng.,
Febru-
ary
6, 130-134 (1961).
54.
Partridge, E. P., Hydrogen damage in power boilers,
Trans.
ASME,
J.
Eng. Power,
July,
31
1-320
(1964).
55.
Glaser, W., and Wright, I. G.,
Mechanically Assisted Degradation,
pp.
136-144.
56.
Corrosion fatigue, in
Corrosion Basics-An Infroduction,
NACE, Houston, TX,
1984.
57.
Tatnall, R. E., MIC: A corrosion engineer’s enigma?,
Mater. Pegorm.,
August,
56 (1988).
58.
Pollock, W. I., What is MIC?,
Mater. PerJorm.,
August,
56 (1988).
59.
Scott,
P.
J.
B.,
Goldie, J., and Davies,
M.,
Ranking alloys for susceptibility to MIC-A preliminary
report on high-Mo alloys
(l),
NACE, Material Per$ormunce,
January,
55-57 (1991).
60.
Kobrin,
G.,
Corrosion by microbiological organisms in natural waters,
NACE, Materials Perfor-
munce,
July,
3842 (1976).
61.
Pope,
D.
H.,
Duquette, D. J., Arland,
J.
H., and Wayner, P. C., Microbiologically influenced
corrosion of industrial alloys,
NACE, Materials Performance,,
April,
14-1
8
(1984).
62.
Pope, D.
H.,
Soracco, R. J., and Wilde, E. W., Studies on biologically induced corrosion in heat
exchanger system at the Savannah River Plant, Aiken, SC,
NACE, Materials Performance,
July
1982,
pp.
43-50.