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PRODUCT INFORMATION

WELL-KEEPER

INTRODUCTION may eventually cause failure. In the past when boiler
designs were simpler, complete drying was possible,
The prevention of corrosion in boilers and in feed and dry stand-by represented a practical method of
water and return line associated with them has been storage. In today’s large boilers with their numerous
a major problem for several decades. Corrosion can complex circuits and bends made it difficult to
attack iron, copper or nickel. General corrosion or completely dry a boiler in preparation for storage. For
pitting may occur for conventional reasons, e.g. , this reason, wet storage normally offers the most
dissolved oxygen, low pH presence of deposits, positive method of protection for large utility boiler.
stagnant area, stress in metals, defects in metal
composition or surface conditions. Dissolved oxygen
often will cause pitting attack when coupled with ADVANTAGES
certain other condition such as deposits on the metal
surfaces or metal defects. The oxygen will oxidize 1. Reduce corrosion rate in boiler.
ferrous hydroxide film to magnetite (Fe 3 O 4 ) or to 2. Reduce cost due to direct replacement and repair
hydrates ferric oxide. This oxidation will occur at a costs.
finite distance from the metal, allowing move iron to 3. Reduce cost due to indirect losses due to
dissolve at the surface under this somewhat porous downtime.
corrosion product. Corrosion is the oxidation of metal
by some oxidizing agent in the environment. As
corrosion proceeds, electrons flow between these APPLICATIONS
areas through the metal, while ions migrate through
the solution. This system constitutes an Clean and empty all deposit from heating surface.
electrochemical cell. In boilers, the oxidation of iron is Then continuously fill the boiler with water containing
accomplished by the reduction of the hydrogen ions chemicals. Dosage varying from 0.3 - 0.5% of boiler
supplied by the hot water. water depends on period of storage.

3Fe + 4 H 2 O ⇋ Fe 3 O 4 + 4H 2 (1)
STORAGE
Incase of acidic water the reaction is Store in cool dry place, away from open flame and
combustible materials.
2+
+
H + Fe ⇋ Fe + H 2 (2)

The reaction of Eq. (1) is Self-limiting on account of PACKAGING
the barrier of Fe 3 O 4 that forms on the surface of the
metal. The reaction of Eq. (2), on the contrary, WELL-KEEPER is available in lined plastic bag of 50
continues until the boiler, only slightly impeded by Kgs. net.
polarization. Both reactions are opposed, however,
by an irreversible potential called the hydrogen
overvoltage, which is markedly affected by the PRECAUTION
condition of the surface of the surface of the metal. Harmful if swallowed. Avoid breathing dust. Keep
WELL-KEEPER that raise the overvoltage oppose, or container closed when not in use. Wash thoroughly
inhibit corrosion. WELL-KEEPER is an inhibitor to after handling. In case of swallowed, drink a large
prevent corrosion of ferrous and non ferrous metal quantity of milk or egg white. Call a physician
and alloy surface in idle boilers. immediately.

PURPOSE

The protection of non-operating boilers is frequently
neglected. Although the total amount of such
corrosion localized in the form of pits which are liable
to become enlarged during normal operation any

TECHNICAL SERVICE
WELLMAN CO.,LTD HAS A STAFF OF TECHNICAL SERVICE
ENGINEERS WHO WILL ASSIST AND TRAIN YOUR MEN ON THE PROPER
EVALUATION AND APPLICATION OF OUR CHEMICALS AND GIVE
RECOMMENDATION TO ENSURE SMOOTH OPERATION
THIS SERVICE IS GIVE FREE OF CHARGE