Ferrule Repair
A Solution to Conventional plastic or ceramic Ferrules
Metallic, thin walled sleeves were introduced in 1981. They
are inserted and then expanded, either
mechanically, hydraulically, or by a combination
of the two, into the existing tube
ends.
Previous attempts to correct
tube end erosion and corrosion have included the
use of conventional ferrules made of plastic or
ceramics. Such conventional ferrules
typically are loose fitting , and normally are
cemented or glued in place.
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Unlike the
tube end sleeve, ferrules cannot return
plugged tubes to circulation and cannot
restore tube to tube sheet joint
strength. Because of their heavy
wall, there is a severe flow reduction
and, at the same time, the creation of a
phenomenon known as end step
erosion. In many cases, the
ferrules have cracked or come loose, and
they cannot effectively be installed to
the tube outlet ends. |
Choosing the proper alloy is critical in the case of
tube sleeve. Material can be chosen from a range of different
alloys. Selection is based on the existing tube materials, the
service of the heat exchanger, and the caused of the tube failures.
Typically, the sleeve alloy selected is superior, but galvanically
compatible, to that of the existing tubes. Options for sleeve
material range from copper based alloys to stainless steel to nicked
based alloys.
Next > Steam/Chemical
Condenser
Repair
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