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Chapter 8
PERCEIVED BOTTLENECKS IN TITANIUM PROCESSING
A major task of the panel was to identify bottlenecks in the titanium
production operations. Bottlenecks, for the purposes of this discussion
are defined as constraints imposed on what might be thought of as an
optimized processing procedure that involves time, resources, and costs.
Also considered to be bottlenecks are weaknesses in the supply chain that
cause expensive delays and that conceivably could become serious
obstacles in certain emergency situations.
Ore
The world titanium ore supply situation was described in Chapter 4.
It was noted that: (1) titanium metal comprises only 7 percent of total
U.S. titanium demand whereas pigment comprises 93 percent, (2) the United
States has ample domestic titanium ore reserves but imported concentrates
provide about 55 percent of U.S. consumption because of lower costs,
(3) imports conserve U.S. reserves, and (4) concentrates for pigment
could provide emergency supplies for metal. Any emergency action,
however, would require considerable coordination of facilities and time
for conversion.
Unlike pigment production that uses considerable domestic ore
sources, the United States imports, most if not all, of the ore used for
domestic titanium metal production. As far as the panel could determine,
the current supply of ore to U.S. plants making titanium tetrachloride
has not suffered major interruptions. It is conceivable, however, that
supply lines could be interrupted extensively in times of hostilities
when long over-the-ocean routes for supply vessels would be vulnerable to
interdiction by hostile forces. A more secure and, in that sense,
favorable situation would prevail if plans for securing a domestic ore
supply for titanium metal production were made before any hostile action
created an emergency. Ti tanium minerals are mined in the United States
and planning for the emergency utilization of ore from such sources
should be implemented. There are no current DOD plans known to the panel
for tapping domestic ores in times of a national emergency; the U.S.
National Stockpile is the sole source immediately available.
Ores for titanium metal production cannot be discussed separately
from titanium tetrachloride and titania (TiO2 f or pigment) production.
The United States has a large domestic capacity for the production of
these commodities, and either could be used as precursor material for the
production of titanium metal. A small part of domestic titanium
87
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tetrachloride production already is being used for titanium metal
production (after required upgrading from the commonly available
commercial product), as shown by its use by three sponge metal producers.
Plans need to be draf ted and mechanisms for implementation need to be
put in place for the utilization of domestic titanium tetrachloride by
the larges t sponge producer, TIMET. TIMET possibly could use titania
TiO2 produced f or pigment ~ in it s chlorinators f or the production of
titanium tetrachloride within its own facilities in times of an emergency
interruption of ores. However, planning for this alternative route has
not been worked out.
Although several companies in the United States make titanium
te trachloride, only one make s a grade suitable f or metal production and
actually sells it for this use, i.e., Gulf & Western (G&W) . For making
the tetrachloride, this company imports considerable ore and the other
part of its ore supply is reported to originate f rom domestic mines. A
detailed breakdown of the amounts and the location of the domestic source
were not available to the panel.
Another company that has a very large capacity to produce titanium
tetrachloride and that achieves considerable ore production from domestic
mines does not supply titanium tetrachloride to the metal producers. It
is understood, however, that tests and negotiations are under way to do
this. This company could make a metal grade of titanium tetrachlori de
since the company was a metal producer in prior year s . Talks should be
conducted and arrangements and plans made for the utilization of the
product from this plant for metal production so that its titanium
tetrachloride could be made available quickly in times of a national
emergency.
Considering all of the above, there currently are no bottlenecks in
ore supply or processing since that aspect essentially could be bypassed
in domestic titanic sponge production.
Titanium Tetrachloride
The description of titanium tetrachloride production in the United
States was covered largely in the previous section on ore. No
bottlenecks were described by the major domestic metal producer (TIMET)
In its production of titanium tetrachloride for its own use or by the
other metal producers who buy t itanium tetrachloride from the current
single U.S. supplier. Although an intensive study of the production of
this commodity was not conducted by the panel, it has identified some
potentially vulnerable areas related to titanium tetrachloride production
that meri t study. For example, one must determine how secure TIMET
production is with respect to such factors as reserve capacity,
dependence on a single source of power from a vulnerable utility (dams
and hydroelectric stations being prime candidates for sabotage), and
supply of necessary augmenting chemicals to produce titanium
tetrachloride (e.g. , petroleum coke).
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Additional questions can be raised regarding the production by the
company that sells titanium tetrachloride to the other metal producers
~ G&W) . Further, it should be of some concern that just two companies
provide the entire precursor product for the entire domestic production
of titanium metal. Plans for alternative sources should be studied.
There is still another area of vulnerability regarding titanium
te trachloride supply--that of transporting the product to the users . In
the case of TIMET, there is no transportation problem since titanium
te trachloride i s made on the s ite where it i s used .
trachloride to RMI
Similarly, there is
no problem in transporting the te trachloride to RMI f rom G&W, the
producing company, since it ~ s only one city block removed f ram the user
and direct transport is by pipeline. Tank cars are used to ship titanium
tetrachloride to D-H Titanium in Freeport, Texas, and to OREMET in
Albany, Oregon. These extensive transportation routes are vulnerable.
Moreover, the supply system is dependent on a specific type of tank car.
As previously stated, no bottlenecks were found in the normal
sequence of supplying titanium tetrachloride to metal producers. Even
though specific studies to reveal possible bottlenecks were not conducted
by the panel, enough is known about the limitations of the titanium
tetrachlor~de supply system to cause concern should there be an emergency
situation. Studies of the supply adequacy of this commodity should be
made and planning should go forward to ensure a reliable supply of this
vital precursor material to the metal producers.
Titanium Sponge
The domestic production of sponge titanium was studied at length.
Immediately prior to the NMAB study--and continuing during the early part
of its investigation--a sponge shortage resulted from inadequate (albeit
probably caused by an "art if icial" shortage due to panic buying and
double ordering ~ domestic sponge production capacity . That shortage now
has been alleviated. Nevertheless, bottlenecks in the production of
sponge should be addressed. For example, the two largest domestic
producer s are making sponge with outmoded technology and equipment . The
limited expansion and renovation of facilities now in progress by these
two companies to improve the production of sponge may be inadequate In
case of a national emergency. Other domestic titanium sponge producers
are smaller and account for far less quantities of sponge, but they use
more modern facilities--in some cases, not yet even In place, however.
The fact that the product of the largest domestic producer of
titanium sponge (TIMET) is unsuitable and the product of the second
largest domestic producer (RMI) is marginal for the ingot melting
furnaces of the domestic nonintegr~ted producers, may be considered to be
a weakness in the capabilities of the titanium industry. In fact, in a
national emergency that involved the stoppage of all imported
vacuum-distilled sponge, the situation would be a real bottleneck because
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go
of the elimination of the melting capacity of the nonintegrated
producer s . At pre sent, the one small producer of U . S . vacuum-dis t tiled
sponge plus the currently planned production of vacuum-distilled sponge
by a company now constructing facilities, and a further expansion of
domestic electrolytic sponge titanium production should alleviate the
problem to some extent, perhaps totally. This would depend on the
achieved production from the newer facilities and the timing.
Thus, there is a perceived bottleneck in sponge titanium supply.
Specific processing bottlenecks identified are that:
1. Reaction pots for titanium sponge production by the major
producers are of small capacity and probably too few in number.
Excessive time and labor are required to remove sponge from the
reactor pots.
3. The leach, wash, and drying time required for "purifying" newly
won titanium metal is quite long and results, in some cases, in
an environmental handling and disposal problem (exceptions are
those cases for RMI and D-H Titanium that generate no disposable
by-products).
In one case, a sponge-inspection, hand-sorting line is necessary
to remove contaminated pieces of sponge (discolored), an
expensive and time-consuming operati on.
The recycling of pots and by-products is expensive and
time-cons~ming.
6. A current weakness, potentially a bottleneck, is the dependence
of the nonintegrated ingot melters on imported titanium sponge.
Ingot and mill product production from nonintegrated companies
would be seriously curtailed in the event of an interruption of
imported titanium sponge.
These bottlenecks may or may not be subject to alleviation by
piecemeal improvement of the specific operations per se. It may be fair
to say, however, that the bulk of domestic sponge production facilities
are in need of a gross overhaul; outmoded equipment should be replaced
and technology updated. Plans have been made to accomplish that
objective given the proper incentives.
Ingot Melting
Specific bottlenecks identified in the conversion of titanium sponge
to ingots are that:
1. Sponge lots of various impurity contents must be blended with
alloy additions and scrap constituents must be blended to
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2.
3.
5.
prepare specific compositional charges for melting. This is a
time-consuming limitation associated with the overall melting
operations. Also, the need to provide many alloys and grades of
alloys is In itself a bottleneck in the production of ingot
titanium.
In many cases, to prepare consumable electrodes for melting,
individual pieces of scrap titanium are hand-welded to construct
an electrode shape, which is a time-consuming operation. In all
cases, great care must be taken essentially to custom-build the
electrodes.
Melting-furnace equipment in some melt shops is antiquated.
Melting rate is slower than optimum and controls for electrode
positioning are inadequate. For some purposes, ingot size
limitations are a bottleneck. Larger ingots can be produced
with relatively smaller power requirements, thus increasing the
unit processing efficiency.
4. Customizing compositions for specific customers, a present
common practice, requires the construction of special electrodes
f or the f irst melt , then constructing electrodes in a preferred
manner to achieve ingot homogeneity in the second melt. Double
melting in itself must be considered as a requirement for the
industry and is not a bottleneck. However, the practice of
triple melting ingots to meet the requirements of some
specifications is considered to be a bottleneck. The U.S .
ingot-making capacity is reduced by 10 to 15 percent as a result
of the requirement to triple melt to meet some specif ications .
The claim is that all ingot producers do not have to triple melt
to meet the quality standards of triple-melt material. However,
those producers claiming triple-melt quality after only double
melting are forced to triple-melt to meet the somewhat arbitrary
triple-melt specifications. [The claims are dif f icult to prove
(i.e., it is difficult to prove a negative) since nondestructive
testing techniques are marginal when applied to the problem of
seeking proof s, and there is too little statistical history on
which referees might pass judgment. ~ Thus, triple melting for
premium-quality ingots remains as a requirement and as a
bottleneck in terms of reducing melting capacity f rom what it
would be without this requirement.
There is a lack of adequate personnel who have sufficient
background in melting operations to permit capacity expansion of
ingot production. Whether or not this perception is general or
specific to only a few companies is unknown. Nevertheless,
expansion of U. S. melting capacity is slowed by the shortage of
proper personnel.
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Primary Fabrication
Ingot Surf ace Conditioning
Prior to ingot-breakdown forging operations, some companies perform
extensive surface conditioning whereas other companies do not. Those
that do not pert arm conditioning have found that bloom yields are
essentially the same whether or not ingot surfaces are conditioned.
Thus, a question is raised with respect to the need for this operation.
Perhaps it is necessary for a few companies that, for one reason or
another, do not produce acceptable surfaces on ingots during melting.
The question needs to be resolved, however, so that the surface
conditioning step can be bypassed if it is not needed, which would
decrease processing time and increase production. In this sense, surface
conditioning may be a bottleneck for some companies.
Bloom Forging
Bottlenecks in this operation are related to inadequate soaking
furnace capacity, inadequate press capacity, and inadequate
manipulators. As important as these equipment def iciencies is the
inadequate number of professionally trained personnel who are trained to
monitor metallurgically the breakdown forging operation and to operate
the f orging equipment . All these def iciencies are not always prevalent
at each plant pert arming breakdown forging . However, on an industry-wide
basis, the inadequacies do constitute a bottleneck in the f low of
titanium mill products to the market.
Bloom Conditioning
Almost without exception, rather extensive grinding and cropping
operations are performed on ingot blooms to remove breakdown forging
defects. These operations are responsible for reducing the yield from
ingot and, of course, for increasing processing time . Techniques are
available to reduce the grinding and cropping loss. For example, larger
f orging equipment would permit larger, faster reductions at temperatures
closer to the design-deformation temperature, and optimizing the
fabrication of ingots to bloom would reduce losses. Another possibility,
at least for some companies, would be to permit yttrium additions to the
titanium materials (at the ingot-making stage). It has been shown that
yields are increased markedly for yttrium-containing mater' als. Thus,
the losses from ingot to bloom, ascribed to the ingot-bloom-conditioning
operations, constitute a bottleneck in the processing of titanium.
Although the conditioning operations may not be eliminated completely
with improved fabrication (and alloying) practices, they may be reduced
considerably. Planning for such improvements should be undertaken.
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Billet and Bar
Mo st of the billet and bar currently produced is processed through
GEM rotary forging machines. Some bar is produced in rolling mills.
Because the GEM machines are getting old and, in many cases, are
undersized for the fabrications expected of them, production is
considerably slower than would be the case on better equipment. This
lack of adequate equipment for some fabrications may be considered a
bottleneck.
Almost as important as the reduction machinery for making billet and
bar, the furnacing associated with those operations also has been
reported as lagging. Many operations are plagued by slowdowns due to the
need for furnace maintenance and to inadequate temperature control even
when the furnaces are working. Therefore, this inadequacy of furnacing
for billet and bar manufacturing is considered a bottleneck.
Lack of sufficient trained personnel to schedule and monitor billet
and bar manufacturing and to pert arm the subsequent inspection operations
can be cited as another reason f or extended lead times in the procurement
of these mill products. Such a personnel bottleneck can be corrected
only after a rather lengthy training program is in place.
Flat-Rolled Products
Except for the larger plate products that are produced on a toll
basis in steel mill equipment, about the same problems can be cited with
respect to fabrication equipment, furnace ng, and personnel as were cited
f or the billet and bar operations . The spotty production delays that are
encountered are bottlenecks in the production of f lat-rolled products.
Little is known about bottlenecks in the production of large plates
of titanium at steel mills. One statement made is that titanium blooms
sometimes are given a low priority for fabrications at steel mills and
take a lower position in the fabrication schedule than is merited. One
reason cited is that the steel mill operators and crew are paid on a
weight throughput basis and, since a titanium bloom is light compared to
a steel bloom, they postpone titanium rolling to a time of their own
choosing. A relatively simple correction would be to develop a
labor-management agreement to pay toll on a rolling-time basis or to
otherwise adjust operator and crew wages to afford proper compensation
commensurate with their steel-rolling wage scale (a weight ratio
factor). Until remedied, this ridiculous situation remains as a
bottleneck in the production of titanium plate.
Other semi-products also are rolled in steel mill equipment on a toll
basis. For example, hot band is produced on Steckel mills as precursor
material for hand-mill sheet product in some company operations. A
considerable amount of unalloyed titanium strip also is rolled in steel
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company strip mills. The bottlenecks that might exist In this steel mill
toll processing are unknown. It is known, however, that long scheduling
delays have been experienced. Reportedly, some of these delays result
from too little rolling-mill capacity to afford short-time, turn-around
service in the strip rolling of titanium. Hence, because of scheduling
difficulties, the toll rolling of strip may be considered to be a
bottleneck.
The hand-mill pack rolling of titanium alloy sheet products may be
considered a technological bottleneck, albeit that the hand-mill
processing of thin plates to sheet gauges in packs (within steel
envelopes) is the accepted way to do it. The development of alloys
amenable to strip rolling is one solution; direct powder rolling
described in Chapter 11 is another, and perhaps there are other
solutions. Meanwhile, the hand-m~lling of alloy titanium to sheet
remains a rather slow production operation and is technically a
bottleneck.
Most flat-rolled product is surface-finished after the rolling
operation. Mill scale and contaminated-skin layers must be removed,
flattening often is called for, and inspections are made f or the
detection of defects. The procedures outlined are necessary; however, it
is questionable if the procedures are optimized technically. Therefore,
they possibly constitute a bottleneck in comparison with improved
operations. The real bottleneck exists, however, when the company lacks
specif ic equipment to do a particular job and consequently must send the
product out f or toll services. The transportation time and the toll shop
scheduling for services constitute bottlenecks.
Ro 11-and-Weld Tubing
Titanium tubing most commonly produced is prepared from precursor
strip (unalloyed titanium) by the roll-and-weld (longitudinal-weld)
technique. The strip, after surface conditioning to finish gauge and
final inspection, is slit to width. The strips are coiled and fed into
the tube lines where automatic roll dies and welding turn the strip into
continuous tubing which is cut to length. Lengths of tubing are
individually inspected . Perhaps the processing speed of thi s tube-line
equipment is optimum but it does appear slow. If research and
development could improve the production speed of tube lines, this
technical bottleneck would be alleviated.
Extrusions
A study of an extrusion facility having a high-volume production of
titanium extrusions was not conducted. Bottlenecks in the production of
extrusions, if they exist, were not identified within the segments of the
titanium industry studied by the panel.
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Conventional Powder Metallurgy
The ready availability of sizable quantities of high-purity,
reasonably priced titanium powder, especially titanium alloy powder, i s
not yet. a reality. This powder availability problem represents a
bottleneck to the more extensive use of powder. Quite possibly, thi s
supply problem has resulted in some delays in expanding existing
applications for the limited quantities of powder now available.
The technical requirements for powder handling, consolidation, hot
Ecstatic pressing (HIP), and heat treatment (if needed in addition to
HIP treatments) may be thought of as a bottleneck because of the
extensive scheduling and operations time needed.
Castings
The production of titanium castings also was not extensively
studied. However, in the limited investigation conducted, it was found
that the availability of electrodes from which castings are derived via
the consumable-electrode process is a bottleneck, at least for some
companies. It appears reasonable that this bottleneck could be reduced
by some action determinable by a separate study of the problem. One
solution is suggested in Chapter 11.
The technical problems associated with producing sound,
high-strength, high-ductil~ty, tough castings constitute a bottleneck in
the application of castings. For example, castings for critical
components require 100 percent inspection. Further, castings from some
manufacturers require extensive weld repair. These production
shortcomings constitute a major problem in the appli cation of castings
and may be considered a bottleneck. Although investigated several time s
without success, the development of an optimized titanium casting alloy
might alleviate some of the problems.
Specialty Products
Some of the high-technology products (e.g., rolled shapes, alloy
foi 1, wire, and seamless tubing) fall into the specialty products
category. The production of these items was not studied; therefore,
bottlenecks in their production are unknowns.
General Comments to Bottleneck
Custom-Job-Shop Status
The titanium industry is largely a custom-job-shop metal operation.
As such, by definition and practice, it is inherently a production of end
products by starts and stops with the accumulation of ~n-process and
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expensive inventories, and we th seemingly end, ess checks and inspections
that of ten require ad justments in scheduling with frequent
decision-making interruptions. Thus, the entire system--the nature of
the business- way be considered a bottleneck-prone production system
compared with the production of mass-produced standard products. Some
relief of this condition might be found in the development of a more
standard line of products acceptable to a broad base of less
discriminating users.
Although not studied in any depth, it is believed that the excessive
transport of in-process products both wl thin plants (cross-hauling) and
between plants ( someti mes by the distance of half a continent )
constitutes a bottleneck to the efficient production of titanium
products. This problem might be alleviated by consolidating the
production facilities at single sites, by acquiring the equipment and
facilities now used on a toll basis, and by restructuring production
lines within plants (to reduce cross-hauling).
Ti tanium Tonnage Powder Metallurgy
The titanium production system described above is like a Gordian
knot--unravelable except by the stroke of a sword. For titanium mill
processing, the sword may be tonnage powder metallurgy (TPM), not for
complex powder metallurgical shapes weighing ounces or pounds but for
mill products weighing tons. However, the TPM solution is by no means
certai n; this is discussed in Chapter 11.
Summary
Perceived bottlenecks and weaknesses at the various titanium
processing stages are summarized below (comments on their poSsi ble
alleviation were of f e red in the preceding text ~ .
Proce ss Stage
Ore
Titanium Tetrachloride
Bottlenecks or Weaknesses
Foreign source is a weakness.
Long overwater transport is vulnerable.
Only two plants as sources for the entire
domestic sponge titanium production is a
weakness. (A third has now come on-stream.)
Long ~ overland ~ ral1 transport of titanium
tetrachloride to three producers of titanium, in
special rail cars, is a weakness.
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Titanium Sponge Inadequate capacity was a bottleneck that appears
to have been alleviated.
Inadequate quality of sponge to serve all melters
is a weakness.
Reaction pots of small size is a bottleneck.
Method of removing sponge f ram pots is a
bottlenec k.
Methods of post-winning purification of sponge
may be a bottleneck.
Di sposal of by-product acid-leaching wastes is
uneconomic and environmentally undesirable.
Auxiliary processes may be bottleneck.
Batch, rather than continuous, winning is a
bottleneck.
Dependence of the nonintegrated melter s on
imported sponge is currently a weakness.
Ingot Melti ng The customizing of alloys and grades of titanium
product for customers is a bottleneck.
The necessity for blending sponge and scrap
grades to prepare ingot compositions is a
bottleneck.
The construction of consumable electrodes f or
melting i s a bottleneck.
Insufficient numbers and sizes of melt furnaces
are bott lenecks .
The necessity for triple melting some ingots to
meet special specifications is a bottleneck.
The size limitations on ingots may be considered
a bottleneck.
A shortage of adequately trained personnel may be
considered a bottleneck.
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Primary Fabrication
Bloom Forging
The necessity of surf ace conditioning ingots may
be a bottleneck.
Inadequate furnace pert ordnance and capacity is a
bottleneck.
Inadequate press function is a bottleneck.
Inadequate manipulator equipment ~ s a bottleneck.
A shortage of personnel properly trained f or
conducting and monitoring the bloom forging
operations is a bottleneck.
Bloom Conditioning The necessity for extensive bloom conditioning is
a bottleneck.
Billet and Bar Inadequate def ormation equipment i s a bottleneck.
Flat-Ro lied
Products
Ro 11-and-Weld
Tubing
Inadequate furnace pert ormance and capacity ~ s a
bottleneck.
A shortage of personnel properly trained f or
conducting and monitoring def ormation operations
is a bottleneck.
Furnacing and handling equipment and personnel
inadequacies may be considered as bottlenecks for
selec ted operas ions .
The necessity to toll out fabrication, surface
finishing, and inspection operations ~ s a
bottleneck.
The technological requirements f or producing
alloy sheet s are bottlenecks .
The low production rate of the tube lines is a
bottleneck.
Produc Lion not studied; bat tlenecks unknown.
Powder Metallurgy The unavailability of low-cost, high-qualit>-
titanium powder is a bottleneck.
The necessity for multiple, technically precise
operations in making complex-shape PM titanium
products may be considered a bottleneck.
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Castings
The ready availability of consumable elec bodes
for cast products is a bottleneck in some cases.
The necessity f or extensive weld repair and 100
percent inspection is a bottleneck.
Specialty Products Production was not studied; bottlenecks unknown.
General
The custom-job-shop nature of the titanium metal
industry may be considered as a bottleneck to the
more ef f icient production of ti tanium product s .
The excessive cross-hauling of materials within
plants and the extensive transportation of
products between plants ~ including transportation
of products to be serviced on a toll basis)
constitutes a bottleneck to the more expedient
production of titanium products .
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Representative terms from entire chapter:
titanium metal
