Transformer Repair vs Buy New, Pros and Cons
Transformers tend to be reliable pieces of electrical equipment and if not abused, last for 30,40, 50+ years depending on their application and operating environment. Failure rates vary from <1% for Power Transformers to 1-2% for Distribution Transformers. Notwithstanding, all transformers will eventually fail, there is no cure for old age.
The transformer owner may have some advance warning of the impending doom if there is regular monitoring of transformer condition with oil testing and regular maintenance. Some transformer operators will systematically remove transformers from service in advance of a failure, and other will run the equipment to failure. Despite the transformer owners' best intentions, often a transformer will fail as the results of an unpredictable event such as a lightning strike, voltage surge, failure of adjacent equipment or the "last straw" of a life well lived.
Factors Affecting the Repair vs the Buy New Options
Size and Age
It is typically not practical to rewind transformers that are smaller than 1500kVA. It will be cheaper and faster to look for a used replacement or a new replacement transformer.
Transformers older than 50 years tend to be poor candidates for extensive repair since the loss characteristics core laminations are much pooer than more modern transformers and the total economic evaluation points to new replacement unless there are extenuating circumstance such as fast turn around time or the need to exactly match the original tank/bushing configuration.
Turn Around Time
Depending on the failure damage, the usual cycle time for a rewind is less than buying a new transformer because of the Repair Facilities ability to focus on the project dependent of course on Factory loading.
Again, depending on the failure damage, repair can be an economical choice. Even the worst case scenario of a three-phase complete re-wind, the core, tank and accessories will be reused resulting in a significant price advantage over buying new.
3L2R Inc. Capabilities
3L2R Inc. has a 40 Ton crane capacity with 36 ft. to the hook which enables the handling of transformers up to - 25 MVA at a voltage rating of 120 kV. Our winding machines have the capacity of making larger windings than the crane size/headroom limiting capability.