the new
Heat Transfer
standard in
Storage, Installation, Operation and Maintenance
Heat Exchangers
This bulletin has been prepared as an aid
and guide to maintenance personnel. Read it
thoroughly prior to installation of any ITT Heat
Transfer heat exchanger in order to ensure
correct installation and best performance.
NOTE: Before placing this equipment
in operation, environment and service
conditions should be checked for
compat ibility with materials of
construction. Contact your nearest ITT
Heat Transfer representative if you are
not sure what the actual materials of
construction are.
Storage
Successful performance of heat transfer
equipment, length of service and freedom
from operating difficulties are largely
dependent upon:
1. Proper thermal design.
2. Proper physical design.
3. Storage practice prior to installation.
4. Manner of installation, including design
of foundation and piping.
5. The method of operation.
6. The thoroughness and frequency
of cleaning.
7. The materials, workmanship, and tools
used in maintenance and making repairs
and replacements.
Failure to perform properly may be due
to one or more of the following:
1. Exchanger being dirty.
2. Failure to remove preservation
materials after storage.
3. Operating conditions being different
than design conditions.
4. Air or gas binding.
5. Incorrect piping connections.
6. Excessive clearances between
internal parts due to corrosion.
7. Improper application.
ITT Heat Transfer heat exchangers are protected against the elements during shipment. If
they cannot be installed and put into operation
immediately upon receipt at the jobsite,
certain precautions are necessary to prevent
deterioration during storage. Responsibility
for integrity of the heat exchangers must be
assumed by the user. ITT Heat Transfer will
not be responsible for damage, corrosion or
other deterioration of heat exchanger equipment
during transit and storage.
Good storage practices are important, considering
the high costs of repair or replacement, and the
possible delays for items which require long lead
times for manufacture. The following suggested
practices are provided solely as a convenience
to the user, who shall make his own decision on
whether to use all or any of them.
On receipt of the heat exchanger, in spect
for shipping damage to all protective
1
covers. If damage is evident, inspect for
possible contamination and replace protective covers as required. If damage is
extensive, notify the carrier immediately.
If the heat exchanger is not to be placed
in immediate service, take precautions
2
to prevent rusting or contamination.
Heat exchangers for oil service, made
of ferrous materials, may be
3
pressure-tested with oil at the factory. However, the residual oil coating
on the inside surfaces of the exchanger
does not preclude the possibility of rust
formation. Upon receipt, fill these
exchangers with appropriate oil or coat
them with a corrosion prevention compound for storage. These heat exchangers
have a large warning decal, indicating
that they should be protected with oil.
The choice of preservation of interior
surfaces during storage for other service
4
applications depends upon your system
requirements and economics. Only when
included in the original purchase order
specifications will specific preservation
be incorporated prior to shipment from
the factory.
Remove any accumulations of dirt,
water, ice or snow and wipe dry before
5
moving exchangers into indoor storage.
If unit was not filled with oil or other
preservative, open drain plugs to remove
any accumulated moisture, then reseal.
Accumulation of moisture usually
indicates rusting has already started and
remedial action should be taken.
Store under cover in a heated area, if
possible. The ideal storage environment
6
for heat exchangers and accessories
is indoors, above grade, in a dry,
low-humidity atmosphere which is
sealed to prevent entry of blowing
dust, rain or snow. Maintain tempera-
tures between 70°F and 105°F (wide
temperature swings may cause condensation and “sweating” of steel parts).
Cover windows to prevent temperature
variations caused by sunlight. Provide
thermometers and humidity indicators at
several points, and maintain atmosphere
at 40% relative humidity or lower.
In tropical climates, it may be necessary
to use trays of renewable dessicant (such
7
as silica gel), or portable dehumidifiers,
to remove moisture from the air in the
storage enclosure. Thermostatically
controlled portable heaters (vented to outdoors) may be required to maintain even
air temperatures inside the enclosure.
Inspect heat exchangers and acces-
sories frequently while they are in
8
storage. Start a log to record results
of inspections and maintenance
performed while units are in storage.
A typical log entry should include, for
each component, at least the following:
a. Date
b. Inspector’s name
c. Identification of unit or item
d. Location
e. Condition of paint or coating
f. Condition of interior
g. Is free moisture present?
h. Has dirt accumulated?
i. Corrective steps taken
2
If paint deterioration begins, as
9
evidenced by discoloration or light
rusting, consider touch-up or repainting.
If the unit is painted with our standard
shop enamel, areas of light rust may be
wire brushed and touched-up with any
good quality air-drying synthetic enamel.
Units painted with special paints (when
specified on customers’ orders) may
require special techniques for touch-up or
repair. Obtain specific information from
the paint manufacturer. Painted steel
units should never be permitted to rust
or dete riorate to a point where their
strength will be impaired. But a light
surface rusting, on steel units which will
be re-painted after installation, will not
generally cause any harm. (See Items 3
and 4 for internal surface preservation.)
If the internal preservation (Items 3 and
10
4) appears inadequate during storage,
consider additional corrosion prevention
measures and more frequent inspections.
Interiors coated with rust preventive
should be restored to good condition and
re-coated promptly if signs of rust occur.
CAUTION:
Provide fire extinguishers,
fire alarms or telephone to
protect building and equip ment against fire damage.
Be sure that the building and
storage practices meet all
local, state, and federal fire
and safety codes!
Installation Planning
On removable bundle heat exchangers,
provide sufficient clearance at the station-
1
ary end to permit the removal of the tube
bundle from the shell. On the floating
head end, provide space to permit removal
of the shell cover and floating head cover.
On fixed bundle heat exchangers, provide
sufficient clearance at one end to permit
2
removal and replacement of tubes and at
the other end provide sufficient clearance
to permit tube rolling.
Provide valves and bypasses in the
piping system so that both the shell
3
side and tube side may be bypassed to
permit isolation of the heat exchanger for
inspection, cleaning and repairs.
Provide convenient means for frequent
cleaning as suggested under maintenance.
4
Provide thermometer wells and pressure
gauge pipe taps in all piping to and from
5
the heat exchanger, located as close to the
heat exchanger as possible.
Provide necessary air vent valves for the
heat exchanger so that it can be purged to
6
prevent or relieve vapor or gas binding on
both the tube side and shell side.
Provide adequate supports for mounting
the heat exchanger so that it will not
7
settle and cause piping strains.
Foundation bolts should be set accurately. In concrete footings, pipe sleeves
at least one pipe size larger than the bolt
diameter slipped over the bolt and cast
in place are best for this purpose as they
allow the bolt centers to be adjusted
after the foundation has set.
Install proper liquid level controls
and relief valves and liquid level and
8
temperature alarms, etc.
Install gauge glasses or liquid level
alarms in all vapor or gas spaces to
9
indicate any failure occurring in the
condensate drain system and to prevent
flooding of the heat exchanger.
Install a surge drum upstream from the
heat exchanger to guard against pulsation
10
of fluids caused by pumps, compressors or
other equipment.
Do not pipe drain connections to a
common closed manifold; it makes it more
11
difficult to determine that the exchanger
has been thoroughly drained.
3
Installation at Jobsite
CAUTION:
Dress properly for the job. You may need
any number of special items — safety
hat, safety shoes, goggles, heavy gloves,
ear protective devices, etc., for your own
protection. Find out what items are required
and wear them.
CAUTION:
A heat exchanger is a pressure
vessel designed for operation at certain
specific limits of pressure and temperature. The cooling or process system,
which includes the heat exchanger, must
be safeguarded with safety valves and
controls so that these heat exchanger
design conditions are not exceeded. All
operating personnel should be made
aware of these specific design pressures
and temperatures.
CAUTION:
Many heat exchangers circulate fluids
which are irritating or dangerous to the
human system. These fluids could cause
problems if bolted or threaded joints are
not maintained in a leak-tight condition
at operating pressures, temperatures and
no-flow, ambient conditions.
If fluids are not irritating or dangerous, a
leak will at least cause a slippery situation
on the floor below.
Because one fluid in the heat exchanger
is at higher temperatures, any leaks might
cause burns.
If you have maintained the heat
exchanger in storage, thoroughly inspect
1
it prior to installation. Make sure it is
thoroughly cleaned to remove all preservation materials unless stored full of the same
oil being used in the system, or the coating
is soluble in the lubricating system oil.
If the exchanger was oil-tested by ITT
Heat Transfer and your purchase order
did not specify otherwise, the oil used
was Tectyl 754, a light-bodied oil which
is soluble in most lubricating oils. Where
special preservations were applied,
you should consult the preservative
manufacturer’s product information data
for removal instructions.
If the heat exchanger is not being stored,
inspect for shipping damage to all
2
protective covers upon receipt at the
jobsite. If damage is evident, inspect for
possible contamination and replace
protective covers as required. If damage is
extensive, notify the carrier immediately.
Operation
Be sure entire system is clean before
starting operation to prevent plugging of
1
tubes or shell side passages with refuse.
The use of strainers or settling tanks in
pipelines leading to the heat exchanger is
recommended.
Open vent connections before starting up.
2
Start operating gradually. See Table 1
for suggested start-up and shut-down
3
procedures for most applications. If in doubt,
consult the nearest ITT Heat Transfer
representative for specific instructions.
After the system is completely filled with the
operating fluids and all air has been vented,
4
close all manual vent connections.
1.800.447.7700 www.itt.com
When installing, set heat exchanger level
and square so that pipe connections can be
3
made without forcing.
Before piping up, inspect all openings
in the heat exchanger for foreign
4
material. Remove all wooden plugs, bags
of dessicant and shipping covers immediately prior to installing. Do not expose
internal passages of the heat exchanger
to the atmosphere since moisture or
harmful contaminants may enter the unit
and cause severe damage to the system
due to freezing and/or corrosion.
After piping is complete, if support cradles or
feet are fixed to the heat exchanger, loosen
5
foundation bolts at one end of the exchanger
to allow free movement. Oversized holes in
support cradles or feet are provided for this
purpose.
If heat exchanger shell is equipped with
a bellows-type expansion joint, remove
6
shipping supports per instructions.
Re-tighten bolting on all gasketed or packed
joints after the heat exchanger has reached
5
operating temperatures to prevent leaks and
gasket failures. Standard published torque
values do not apply to packed end joints.
Do not operate the heat exchanger
under pressure and temperature
6
conditions in excess of those specified
on the nameplate.
To guard against water hammer, drain
condensate from steam heat exchangers
7
and similar apparatus both when starting
up and shutting down.
Drain all fluids when shutting down to
eliminate possible freezing and corroding.
8
4
In all installations there should be no pul-
sation of fluids, since this causes vibration
9
and will result in reduced operating life.
Under no circumstances is the heat
exchanger to be operated at a flowrate
10
greater than that shown on the design
specifications. Excessive flows can cause
vibration and severely damage the heat
exchanger tube bundle.
RECOMMENDED START-UP AND SHUT-DOWN PROCEDURES
CAUTION: Every effort should be made to avoid subjecting the unit to thermal shock, overpressure, and/or hydraulic hammer, since these conditions
may impose stresses that exceed the mechanical strength of the unit or the system in which it is installed which may result in leaks and/or other damage
to the unit and/or system.
Fluid Location & Relative Temp.
Heat Exchanger
Type of
Construction
Liquid Hot Liquid Cold
Condensing Liquid
Gas Hot or Cold
(e.g., steam) Gas
Fixed Tubesheet
(Non-Removable
Gas Hot Liquid Cold
Bundle)
Liquid Cold Liquid Hot
Liquid Cold Gas Hot
Liquid Hot Liquid Cold
U-Tube
Condensing Liquid
Packed Floating
Gas Hot or Cold
Head
(e.g., steam) Gas
Packed Floating
Tubesheet
Gas Hot Liquid Cold
Internal Floating
Head
Liquid Cold Liquid Hot
(All these types have
Removable Bundles)
Liquid Cold Gas Hot
Shell Side
Type of
Fluid
Rel.
Temp.
Heat exchangers that are out of service
for extended periods of time should be
11
protected against corrosion as described
in the storage requirements for new heat
exchangers.
Heat exchangers that are out of service
for short periods and use water as the
flowing medium should be thoroughly
drained and blown dry with warm air,
TABLE 1
Tube Side
Type of
Fluid
Rel.
Temp.
Start both fluids gradually Shut down both fluids gradually
at the same time. at the same time.
Start hot fluid first, then slowly Shut down cold fluid first, then
start cold fluid. Avoid temperature hot fluid.
shock. (1)
Start cold fluid first, then hot fluid. Shut down cold fluid gradually,
then hot fluid.
Start both flows gradually at the Shut down both fluids gradually
same time. at the same time.
Start cold fluid first, then hot fluid. Shut down hot fluid first, then
cold fluid.
Start cold fluid first, then start Shut down hot fluid first, then
hot fluid gradually. cold fluid.
Start cold fluid first, then start Shut down cold fluid first, then
hot fluid gradually. shut down hot fluid gradually.
Start cold fluid first, then start Shut down hot fluid first, then
hot fluid gradually. cold fluid.
Start cold fluid first, then start Shut down hot fluid first, then
hot fluid gradually. cold fluid.
Start cold fluid first, then start Shut down hot fluid first, then
hot fluid gradually. cold fluid.
Start-Up
Procedure
if possible. If this is not practical, the
water should be circulated through the
heat exchanger on a daily basis to prevent stagnant water conditions that can
ultimately precipitate corrosion.
Shut-Down
Procedure
General Comments:
1.) In all start-up and shut-down operations, fluid flows should be regulated so as to avoid thermal shocking
the unit regardless of whether the unit is of either a removable or non-removable type construction.
2.) For fixed tubesheet (non-removable bundle) type units where the tube side fluid cannot be shut down, it is recommended that:
a) A bypass arrangement be incorporated in the system; and, b) the tube side fluid be bypassed before the shell side fluid is shut down.
3.) Extreme caution should be taken on insulated units where fluid flows are terminated and then restarted.
Since the metal parts could remain at high temperatures for an extended period, severe thermal shock could occur.
5
Maintenance
Clean exchangers subject to fouling
(scale, sludge deposits, etc.) periodi-
1
cally, depending on specific conditions.
A light sludge or scale coating on either
side of the tube greatly reduces its
effectiveness. A marked increase
in pressure drop and/or reduction in
performance usually indicates cleaning is
necessary. Since the difficulty of cleaning
increases rapidly as the scale thickens or
deposits increase, the intervals between
cleanings should not be excessive.
Neglecting to keep tubes clean
may result in random tube plugging.
2
Con sequent over heating or cooling of
the plugged tubes, as compared to
surrounding tubes, will cause physical
damage and leaking tubes due to differential thermal expansion of the metals.
To clean or inspect the inside of the
tubes, remove only the necessary tube
3
side channel covers or bonnets, depending on type of exchanger construction.
If the heat exchanger is equipped with
sacrificial anodes or plates, replace these
4
as required.
To clean or inspect the outside of the
tubes, it may be necessary to remove the
5
tube bundle. (Fixed tubesheet exchanger
bundles are non-removable).
When removing tube bundles from heat
exchangers for inspection or cleaning,
6
exercise care to see that they are not
damaged by improper handling.
•Theweightofthetubebundleshould
not be supported on individual
tubes but should be carried by the
tube sheets, support or baffle plates or
on blocks contoured to the periphery
of the tube bundles.
•Do not handle tube bundles with hooks
or other tools which might damage tubes.
Move tube bundles on cradles or skids.
•To withdraw tube bundles, pass rods
through two or more of the tubes and
take the load on the floating tubesheet.
•Rodsshouldbethreaded at bothends,
provided with nuts, and should pass
through a steel bearing plate at each
end of the bundle.
•Insertasoftwoodfillerboardbetween
the bearing plate and tubesheet face to
prevent damage to the tube ends.
•Screw forged steel eyebolts into both
bearing plates for pulling and lifting.
•As an alternate to the rods, thread a
steel cable through one tube and return
through another tube.
•Ahardwoodspreaderblockmust be
inserted between the cable and each
tubesheet to prevent damage to the
tube ends.
If the heat exchanger has been in service
for a considerable length of time without
7
being removed, it may be necessary to use
a jack on the floating tubesheet to break
the bundle free.
•Use a good-sized steel bearing plate
with a filler board between the
tubesheet face and bearing plate to
protect the tube ends.
Lift tube bundles horizontally by means
of a cradle formed by bending a light-
8
gauge plate or plates into a U-shape.Make
attachments in the legs of the U for lifting.
Do not drag bundles, since baffles or
support plates may become easily bent.
9
Avoid any damage to baffles so that the
heat exchanger will function properly.
STEEL RODS STEEL EYEBOLTS
Tube Rod Safe Load Size Safe Load
Size Size Per Rod
5/8” 3/8” 1,000 lbs. 3/4” 4,000 lbs.
3/4” 1/2” 2,000 lbs. 1” 6,000 lbs.
1” or 1-1/4” 10,000 lbs.
larger 5/8” 3,000 lbs. 1 -1/2” 15,000 lbs.
Some suggested methods of cleaning
either the shell side or tube side are listed
10
below:
•Circulating hot wash oil or light distil-
•Soft salt deposits may be washed out
•Somecommercialcleaningcompounds
Some tubes have inserts or longitudinal
fins and can be damaged by cleaning
11
when mechanical means are employed.
Clean these types of tubes chemically or
consult the nearest ITT Heat Transfer representative for the recommended method
of cleaning.
•Ifthescaleishardandtheabovemethods are not effective, use a mechanical
means. Neither the inside nor the outside of the tube should be hammered
with a metallic tool. If it is necessary to
use scrapers, they should not be sharp
enough to cut the metal of the tubes.
Take extra care when employing scrapers to prevent tube damage.
Do not attempt to clean tubes by
blowing steam through individual tubes.
This overheats the individual tube and
results in severe expansion strains and
leaking tube -to-tubesheet joints.
Table 2 shows safe loads for steel rods
and eyebolts.
12
6
late through tube side or shell side will
usually effectively remove sludge or
similar soft deposits.
by circulating hot fresh water.
such as “Oakite” or “Dowell” may be
effective in removing more stubborn
deposits. Use in accordance with the
manufacturer’s instructions.
TABLE 2
To locate ruptured or corroded tubes
or leaking joints between tubes and
13
tubesheets, the following procedure is
recommended:
•Removetubesidechannelcovers
or bonnets.
CAUTION:
Do not remove channel covers, shell
covers, floating head covers or bonnets
until all pressure in the heat exchanger
has been relieved and both shell side and
tube side are completely drained.
•Pressurizetheshellsideofthe
exchanger with a cold fluid,
preferably water.
•Observetubejointsandtubeendsfor
indication of test fluid leakage.
With certain styles of exchangers,
it will be necessary to buy or make a
14
test ring to seal off the space between
the floating tubesheet and inside shell
diameter to apply the test in paragraph
13. Consult your nearest ITT Heat Transfer
sales representative for reference
drawings showing installation of a test
ring in your heat exchanger.
To tighten a leaking tube joint, use a
suitable parallel roller tube expander.
15
•Donotrolltubesbeyondthebackface
of the tubesheet. Maximum rolling
depth should be tubesheet thickness
minus 1/8”.
CAUTION:
Since many of the removable components of the heat exchanger, particularly in the larger sizes, are too heavy for
people to handle, care must be used to
take this weight with proper rigging to
avoid injury. Wear hard hats and safety
shoes as required.
CAUTION:
Do not thread rods or cables through
tubes of a heat exchanger equipped with
ITT Standard Amatran® tubes, or any
with internal fins.
CAUTION:
When the heat exchanger is cleaned, it is
important that full characteristics of the
fouling material and the cleaning agent
be known and care exercised in handling
them according to instructions. Use eye
protection to prevent damage to your
eyes. Wear a respirator when required.
•Donotre-rolltubesthatarenotleaking
since this needlessly thins the tube
wall.
It is recommended that when a heat
exchanger is dismantled, new gaskets be
16
used in reassembly.
•Composition gaskets become brittle
and dried out in service and do not
provide an effective seal when
reused.
•Metal or metal jacketed gaskets in
initial compression match the contact
surfaces and tend to work-harden and
cannot be recompressed on reuse.
Use of new bolting in conformance with
dimension and ASTM specifications of
17
the original design is recommended where
frequent dismantling is encountered.
CAUTION:
Do not blow out heat exchangers with
air when the normal process fluids or
the cleaning fluids being handled are
inflammable.
7
Warranty
WARRANTY OF SELLER’S PRODUCTS
Except where a different express warranty has been
issued with respect to a particular product, no warranty of any kind, express or implied, is extended by
the seller to any person or persons other than its
direct Buyers. To direct Buyers, the Seller warrants
only that it will furnish by freight a replacement for,
or at its option repair, any product of its manufacture
or part or portion thereof, proved to its satisfaction
to be defective in material or workmanship under
normal use and service (i) within a period of six (6)
months from date of shipment as to those parts
which contain perishable elastomers or (ii) within one
year from the date all other equipment or part thereof
is first placed in use, or two years from the date of
shipment, whichever shall be less.
The Seller shall have no responsibility for the performance of any product sold by it under conditions varying materially from those under which such product is
usually tested under existing industry standards, nor
for any damage to the product from abrasion, erosion,
corrosion, deterioration or the like due to abnormal
temperatures or corrosive fluids or the influence of
foreign matter or energy, or flow induced vibration
caused by associated equipment or external influences; nor for the design or operation of any system
of which any such product may be made a part or for
the suitability of any such product for any particular
application. The Seller shall not be liable for any
cost or expense, including, without limitation, labor
expense, in connection with the removal or replacement of alleged defective equipment or any part or
portion thereof nor for incidental or consequential
damages of any kind, nor under any circumstances
for any damage beyond the price of the goods sold.
Any freight allowance in connection with a replacement will be on the same terms as were applicable
to the original sale, except that a replacement for a
product or part or portion thereof which is proved to
the Seller’s satisfaction to be defective in material or
workmanship as provided herein above, will in any
event be furnished with freight (but not local cartage) allowed, within the country of origin, to the first
destination. Any substitution of parts not of Seller’s
manufacture or not authorized by Seller, or any
modification, tampering, or manipulation of Seller’s
product, shall void the warranty.
Other Warranties — The foregoing warranty is in
lieu of all other warranties of any kind, express or
implied, and of all other obligations or liabilities, on
the part of the Seller. The Seller neither assumes, nor
does it authorize any other person to assume on its
behalf, any other liability in connection with the sale
of its products.
Seller expressly disclaims the implied warranties of
merchantability and fitness for a particular purpose.
Goods of Other Manufacturers — Goods of other
manufacturers sold by the Seller are not warranted
except by express warranties which may be issued
in writing from time to time with respect to a particular product or a particular sale; but the Seller will
endeavor to secure for its direct Buyers the benefits
of warranties extended by the manufacturers of such
goods sold but not manufactured by the Seller.
For more information, please contact:
Lit #104-17
© 2007 ITT
Heat Transfer
175 Standard Parkway • Cheektowaga, NY 14227
800/447-7700 Fax: 716/897-1777
www.itt.com
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