Bell & Gossett HT 50B SM B&G Series U Heat Exchangers Removable Bundle Design User Manual

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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

deteriorate to a point where their strength will be impaired.

A light surface rust, on steel units which can be repainted

after installation, will not generally cause any harm. (See

Items 3 and 4 for internal surface preservation.)

10. If the internal preservation (Items 3 and 4) appears inade-

quate during storage, consider additional corrosion pre-

vention measures and more frequent inspections. Interiors

coated with rust preventive should be restored to good

condition and recoated promptly if signs of rust occur.

INSTALLATION

1. Provide sufficient clearance at the head of the unit to per-

mit removal of tube bundle from shell.

2. Provide valves and by-passes in the piping so that both

the shell and tube bundle may be by-passed to permit iso-

lation of the unit for inspection or repairs.

3. Provide thermometer wells and pressure gauge connec-

tions in all piping to and from the unit and located as near

the unit as possible.

4. Provide convenient means for frequently cleaning the unit

as suggested under “MAINTENANCE.”

5. Provide necessary air cocks for units so they can be

purged to prevent or relieve vapor binding of either the

tube bundle or the shell.

6. Foundations must be adequate so that exchangers will not

settle and cause piping strains. Foundation bolts should

be set to allow for setting inaccuracies. In concrete foot-

ings, pipe sleeves at least one size larger than bolt diame-

ter slipped over the bolt and cast in place are best for this

purpose, as they allow the bolt center to be adjusted after

the foundation has set.

WARNING: All system piping to the heat ex-

changer must be adequately supported. Failure to

do so will result in excessive loads on the heat exchanger

connections causing damage and/or leakage and poten-

tial injury to adjacent personnel.

WARNING: When installing a Diamondback™

heat exchanger above a ceiling or workststion where

personnel are present, it may be necessary to install a

drip pan to collect any tell-tale drip due to internal tube

failure. Failure to do so may result in damage to the

ceiling and potential injury to personnel.

7. Loosen foundation bolts at one end of unit to allow free

expansion of shells. Oval holes in foundation brackets are

provided for this purpose.

CAUTION: Provision must be made to isolate the

heat exchanger from any external vibrations that

cause tube failures within the heat exchanger. Result is

internal leakage and mixing of the hot and cold media.

STORAGE

NOTE: If the heat exchanger cannot be installed and put into

operation immediately upon receipt at the jobsite, certain pre-

cautions are necessary to prevent deterioration during stor-

age. Responsibility for integrity of the heat exchangers must

be assumed by the user. Bell & Gossett 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 fol-

lowing suggested practices are provided solely as a conve-

nience to the user, who shall make his own decision on

whether to use all or any of them.

1. On receipt of the heat exchanger, inspect for shipping

damage to all protective covers. If damage is evident,

inspect for possible contamination and replace protective

covers as required. If damage is extensive, notify the car-

rier immediately.

2. If the heat exchanger is not to be placed in immediate ser-

vice, take precautions to prevent rusting or contamination.

3. Heat exchangers for oil service, made of ferrous materials,

may be 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 forma-

tion. Upon receipt, fill these exchangers with appropriate

oil or coat them with a corrosion prevention compound for

storage.

4. The choice of preservation of interior surfaces during stor-

age for other service applications depends upon your sys-

tem requirements and economics. Only when included in

the original purchase order specifications will specific

preservation be incorporated prior to shipment from the

factory.

5. Remove any accumulations of dirt, water, ice or snow and

wipe dry before 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.

6. Store under cover in a heated area, if possible. The ideal

storage environment for heat exchangers and accessories

is indoors, above grade, in a dry, low humidity atmos-

phere which is sealed to prevent entry of blowing dust,

rain or snow. Maintain temperatures 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 ther-

mometers and humidity indicators at several points, and

maintain atmosphere at 40% relative humidity or lower.

7. In tropical climates, it may be necessary to use trays of

renewable dessicant (such as silica gel), or portable dehu-

midifiers, 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.

8. Inspect heat exchangers and accessories frequently while

they are in storage.

9. If paint deterioration begins, as evidenced by discol-

oration 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)