Transformer Repairs / Valve Stem Repair
A common transformer leak results from packing failure on 4-bolt
flapper and 8-bolt butterfly valve stems. (Figure 1 & 2) Once
the packing deteriorates, compression cannot be sustained by continuing
to tighten the packing nut and therefore leaks develop. To repair
the packing traditionally, the old packing has to be replaced.
Since the valve stem is usually on the transformer side of the
flapper valve closure disc, care must be taken not to spill oil
during the repair process. This entails draining the oil from the
main tank or pulling a vacuum, both time consuming and expensive
procedures.
[ Click images for larger view ]
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Figure 1 |
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Figure 2 |
TDS Repair Technique
TDS drills and taps a hole into the failed packing area allowing
for the temporary installation of an injection valve. (Figures
3 & 4) TDS sealant is then injected into the packing area with
a hydraulic gun. The sealant flows into the packing area until
the void is filled, thereby fixing the leak. TDS's sealant is non-adhering
and rubber based which makes it compressible and oil resistant.
The valve is fully operational after the repair is complete.
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Figure 3 |
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Figure 4 |
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