SPX Waukesha - One of the Best Transformer Manufacturing Companies
SPX Waukesha Quality goes into every Waukesha® transformer we build, whether it is manufactured in Waukesha, WI or Goldsboro, NC. The company has earned the latest ISO 9001:2008 certification (Waukesha, Goldsboro) and has a reputation for quality and reliability that is among the best in the industry. Complying with the SPX Waukesha Quality Policy is the overriding objective and primary responsibility of every SPX Waukesha employee. It means that every unit we build and deliver to our customers has been manufactured to provide consistent performance, dependability and long service life. With nearly 15,000 power transformers installed, the facts speak for themselves: • Lowest incidence of through-fault failure
• Low maintenance due to advanced design
• Long contact life LTCs
• Certified accuracy of loss measurement (compliant with NIST* Technical Note 1204)
• And many other benefits!
Transformer - Company-Wide Quality Policy The overriding objective of SPX Transformer Solutions and primary responsibility of each employee is to provide outstanding products and outstanding services that meet the continuing needs and expectations of our customers.
SPX Transformer Solutions will continually strive to improve the Quality System and customer satisfaction by setting measurable quality objectives at the various functions of the organization, and reviewing the organization’s performance to them.
SPX Waukesha Quality System Our corporate objective is Total Customer Satisfaction and we have structured our quality system so that all completed units meet individual customer specifications and industry standards. To deliver the consistent quality transformers and power equipment that our customers demand, each of our manufacturing operations (Waukesha and Goldsboro) have:
• Trained Quality Specialists and Testers on all shifts
• Several hundred test and measurement items on a rigorous calibration program
• An on-line nonconformance system to resolve issues before a unit ships
SPX Waukesha Quality System covers the following areas of responsibility: Customer Requirements and Specifications
To be sure that our plant and facilities are prepared to meet customer requirements, a systematic review is performed to identity each requirement including special requirements. This allows ample time for preparation in the event that special test or inspection equipment is required.
Since purchased items and raw materials must meet design requirements and specifications, our Quality and Global Sourcing groups work as a team to select only those suppliers capable of delivering materials and products that consistently meet SPX Waukesha quality, manufacturing and technical requirements. Performance requirements are defined and documented for applicable material specifications, engineering instructions and standards data. Our measurement and corrective action systems are functioning to continually improve the quality of supplier products and service.
Once suppliers have been selected, all incoming production materials are subjected to receiving verification. Material not consistent with expectations and specifications is segmented and prevented from use in our manufacturing facilities. A documentation system provides a history of part characteristics and supplier performance.
Manufacturing and Assembly Operations
To confirm that all components and subassemblies manufactured at SPX Transformer Solutions meet design specifications, a documented system of inspection of critical dimensions and attributes takes place at the point where each component is manufactured. This prevents nonconforming components from entering the main transformer assembly bay or supporting assembly operation. The inspection system provides for the identification, segregation and disposition of all nonconforming parts and/or assemblies.
Engineering Change Requirements
When changes are made, the Waukesha Quality team is continually provided with up-to-date computerized Engineering Change Notices to be sure that all components and assemblies are manufactured with the most current engineering information.
Waukesha® transformers must pass an extensive series of inspections and electrical tests, including Impulse and Corona tests — conducted according to ANSI/IEEE and other standards. Additional information can be found in our Transformer Testing section.
Prior to release by manufacturing of a completed transformer, a thorough inspection is made. Specific shipping details requested by the customer are checked, along with essential transportation and vehicle requirements. Working together with the customer, our Quality, Manufacturing, and Engineered Shipping groups work as a team to provide accurate, on time, and damage-free delivery of each Waukesha® transformer.
Copper and silver alloyed copper magnet wire—or continuously transposed copper cable—is used for the winding conductors on all Waukesha® power transformers. Continuously transposed copper cable is used to minimize losses and hot-spot temperatures and to produce a more compact winding with improved short-circuit performance.
All windings are circular, concentric type and provide maximum through-fault withstand capability. High voltage, low voltage and tertiary windings use a continuous-disc or helical winding design exclusively. This construction provides maximum strength and short-circuit withstand capability, increased predictability and lower hot-spot temperatures for loading and overloading.
Multiple conductor continuous disc and helical windings are transposed throughout the winding to minimize circulating current losses. State-of-the-art design techniques are used to provide maximum impulse strength in the windings and to minimize voltage stresses. Special design consideration is also given to the line end discs to control voltage stress distribution.
Ampere-Turn balancing techniques are used to minimize radial leakage flux and to minimize axial short-circuit forces. The conductor insulation allows continuous operation at 65°C average winding temperature rise and 80°C hot-spot temperature rise without abnormal reduction of insulation life.
Cooling ducts are formed between discs in the windings by keyed radial spacers made of special high-density pressboard insulation. These spacers are aligned in column to provide axial support for the windings and high short-circuit strength.
All windings are manufactured in a Clean Winding Environment. This isolated “factory within a factory” is humidity and temperature controlled 24 hours a day with controlled access to minimize contamination.
Core Construction All Waukesha® transformers employ core form construction. Cores are manufactured from high permeability-grade, domain-refined "H" grade, cold-rolled grain-oriented silicon steel ("M" grade steel is used in some applications). Annealing all core steel after slitting provides optimal loss performance.
Core designs utilize a multiple step circular cross section with fully mitered joints. Laminations cut to length on special high-speed, computer-controlled, automatic shears to high dimensional accuracy ensure tight-fitting joints with minimum gaps to minimize core loss, exciting current and sound levels.
Insulating the core from the frame and connecting to ground at only one point prevents any accumulation of static charges. Grounding at a single point also eliminates circulating currents and associated combustible gas generation. The grounding strap is brought out to a convenient location adjacent to an access hole opening on the cover or through a bushing on the tank cover to facilitate testing the core insulation.
After stacking, epoxy polyester shrink tape bind the core legs together to form a rigid structure. Sturdy steel end frames provide a complete core structure of high mechanical strength to withstand heavy stresses during shipment or under short-circuit conditions without distortion of the core or windings.
Core and Coil Assembly — Putting Them Together After the cores are banded together and uprighted and the coils have been wound, processed, pressed and sized, its time to put them together in a process called "landing the coils." Each limb, or leg, of the core will have 2 to 5 windings landed on it after which the entire core and coil assembly goes through a thorough cleaning and careful inspection process before proceeding to a pressing operation. Here we use rigging and hydraulic presses to put the engineering-specified amount of pressure onto the windings. The amount of pressure is based upon the size of the windings and the amount of compressible material in them.
Once the assembly is under pressure, it is cleaned and inspected again and then put through a process called top yoking, where top yoke steel is assembled to the limbs within very close tolerances to ensure no core loss issues on the test floor. Upon completing the top yoking, the unit is “pulled in.” This "pulling in" procedure includes tightening the core clamps onto the steel, tightening up the yoke bands and adding all the extra insulation required in the design. Precise, pre-calculated methods of clamping the core and coil assembly together assure a positive clamping pressure on the coils at every point and provide maximum through-fault protection no matter how dry the transformer may become while in service.
Pre-assembled cleat and lead structures (wood frames with the insulated cable and, oftentimes, a de-energized tap changer assembled to them) are now attached to the assembly. All connections are crimped, with each crimp signed by the operator for quality auditing purposes, and then wrapped according to engineering specifications; special care is taken when wrapping crimps to minimize dielectric stresses. Once all connections are made, the assembly is ratioed and tested again, inspected and then released to Vapor Phase.
Final Dry-Out — Vapor Phase Processing
Final dry-out begins by placing the entire core and coil assembly in one of SPX Waukesha's vapor phase chambers and drawing partial vacuum. Next, solvent vapors are introduced and condense on the assembly, heating it up and causing moisture in the insulation to evaporate.
Once the assembly reaches a uniform temperature, vacuum is reduced and maintained at an extremely low level (typically less than 0.5 torr). This process generally dries the insulation system well below SPX Waukesha's 0.5% moisture content guarantee.
Flooding the vapor chamber with processed transformer oil begins the process of impregnating the insulation materials. After a minimum impregnation hold, all oil is drained and the core and coil assembly removed for final adjustments prior to encasement in its tank. For Large Power units, the core and coil assembly bypasses oil impregnation in the vapor chamber. The core and coil are removed and placed in a low humidity environment to minimize moisture ingress.
After a thorough final inspection, the assembly is immediately tanked and covered with transformer oil to inhibit moisture absorption. The oil is again drained and the transformer placed on high vacuum to remove any surface moisture. Vacuum-filling the transformer with hot processed transformer oil for its final impregnation follows, and, after appropriate "sit time", electrical testing begins.
Many advantages exist by using a Vapor Phase process in the manufacture of power transformers:
Heating of insulation materials under vacuum — Reduced oxygen levels minimize oxidation and thermal aging of cellulose materials, resulting in less loss of life than can be achieved in rapid oven drying or radiation processes.
Excellent heating characteristics of the vapor condensation process — Heat is transferred to all parts of the core and coils uniformly, quickly, and more efficiently than can be achieved with hot air or radiation processes which further reduces thermal aging and loss of insulation life over other drying processes.
Excellent Cleaning Action — Soluble process materials and contaminants are washed off the core and coil assembly in the vapor phase process which is not possible without the condensing vapors.
Transformer Tank Construction
Tank integrity is essential for reliability and long transformer life. To ensure a perfect fit to the application, SPX Transformer Solutions designs all transformer tanks to high internal standards taking customer specifications into account.
Waukesha® transformer tanks feature the following:
Hot-rolled, low carbon steel plates plasma cut to critical tolerances then joined via submerged arc welding to ensure against cracked seams and irregularities.
Tank wall stiffeners brace tank walls to withstand full vacuum and pressures 25% greater than achieved during normal operation.
Bent corners (no corner welds).
Jack pads and lifting hooks for lifting, jacking or pulling.
Guides used to solidly "fit" and brace the completed core and coil assembly inside the tank to prevent shifting during shipment.
Slightly domed covers help prevent water accumulation.
Raised flanges with machined gasket grooves in cover openings.
Conveniently located hand holes and/or manholes for easy access to the lower end of bushings, terminal boards and the upper portion of core and coil assembly.
Additionally, SPX Transformer Solutions' standard coating system exceeds the requirements of ANSI C57.12.28, the specification for pad-mounted equipment:
Hot-rolled, low carbon, A36 plate steel.
Interior surfaces of the tank and cover are thoroughly cleaned and prepared prior to application of the white, two-part, oil-resistant epoxy enamel.
Interior surfaces of the tank and tank cover are coated with white, two-part, oil-resistant epoxy enamel.
Exterior surfaces are primed with a two-part epoxy primer and top-coated using two-part urethane high gloss finish coat.
All coating materials are applied with air-assisted spray guns, with the paint delivered to the guns using plural component equipment that automatically measures and mixes the paint systems to eliminate operator error.
Coatings then "sit" to produce a uniform cured coating.
Interior coating compatible with transformer oil per ASTM 3455 and a 3 mil exterior coating capable of meeting ANSI C57.12.28.
Mineral Oil SPX Transformer Solutions typically uses inhibited mineral oil in its transformers which is refined especially for use in transformers in accordance with ANSI/ASTM D3487. In addition to extensive testing by an independent laboratory to determine approved sources of supply, SPX Waukesha performs acceptance tests on each shipment of oil received.
SPX Waukesha receives its oil in dedicated tank cars and trucks. Samples are taken from the bottom, middle and top of the tank cars before placing the oil in bulk containment units. The new oil is then vacuum degassified and stored for use. SPX Waukesha reprocesses oil again at each point of use throughout the plant. All Waukesha® transformer oil is PCB-free per EPA definition 7-179.
Although mineral oil is the most common insulating fluid used at both plants, other options are available upon request, including Envirotemp™ FR3™ natural ester fluid.
Envirotemp™ FR3™ Natural Ester Fluid
Envirotemp FR3 fluid is a patented, biodegradable, seed-based dielectric fluid designed by Cooper Power Systems. Made from a formulation which includes vegetable oils, FR3 fluid has been proven to add value to new and retrofilled power equipment:
In conjunction with recognized testing organizations, the U.S. Environmental Protection Agency (EPA) created the Environmental Technology Verification (ETV) Program to further environmental protection by accelerating the acceptance and use of innovative, improved and more cost-effective technologies. By objectively and systematically documenting the performance of commercial-ready environmental technologies, the ETV Program intends to assist and inform those individuals in need of credible data before utilizing a new technology.
For a complete listing of all FR3 fluid documents, click here to go the Library section of this website.
The Duval Triangle Diagnostic Tool The Duval Triangle diagnostic tool is used to perform a dissolved gas analysis (DGA) of the insulating oil as a way to evaluate transformer quality. This tool was developed by Michel Duval of IREQ(Hydro-Quebec, Canada) and is recognized in the IEC guidelines.
Sample Duval Triangle This Triangle applies to conventional, compartment-type LTCs where normal operation involves mostly arc breaking in oil.
Feel free to use this tool to help maintain your transformer. If you have questions, please contact us at 1-800-835-2732.
File Type: Microsoft® Excel® File Size: 1.75MB
Dr. Michel Duval Biography
Michel Duval is a senior scientist with Hydro Quebec’s Institute of Research (IREQ) in Canada since 1970. His main topics of interest have been dissolved gas analysis, electrical insulating oils and lithium polymer batteries.
A senior member of IEEE, he holds 13 patents, has authored over 70 scientific papers, book chapters or international standards and is active in several CIGRE and IEC working groups.
M. Duval obtained a B.Sc. in chemical engineering in 1966 and a Ph.D. in polymer chemistry in 1970.
Biography from Dissolved Gas Analysis and the Duval Triangle - By Michel Duval
The Duval Triangle calculation tools and information available on this website are provided with permission from Dr. Michel Duval. All documents and information shown or created through use of the Duval Triangle calculation tools and information on this website (i) are preliminary in nature and reflect certain underlying assumptions that may or may not be applicable to the user’s project, (ii) are provided for informational purposes only, (iii) do not necessarily reflect any consideration or analysis of other factors that may be relevant to the user’s application, and (iv) are provided “AS IS” with no guaranty as to the suitability or completeness for the user’s particular purpose.The user assumes all risk relating to the use of the Duval Triangle calculation tools and information, and SPX Transformer Solutions, Inc., makes no representation or warranties of any kind, express or implied, in relation to any information created or provided through use of the Duval Triangle calculation tools and information. No part of Duval Triangle calculation tools may be copied, modified, used, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without the written permission of the owner.
Fully galvanized, hot-dipped, corrosion-resistant radiators come standard on all Waukesha® transformers. Radiators are manufactured to strict quality standards that ensure highest efficiencies, maximum durability and exceptional corrosion resistance. Both bolt-on and weld-on configurations are available.
Panels are precisely fabricated of heavy gauge, cold roll-formed steel joined through automatic resistance welding. All assembled radiators are fully submerged and pressure-tested to ensure leak-free performance. Radiators are shipped without oil, with end seals, to avoid contamination during transit. Cushioning strips protect equipment in transit.
Maintenance-free radiator shut-off valves, designed with SPX Waukesha's exclusive triple o-ring construction, are supplied with bolt-on radiators.
Control Box Enclosures
SPX Transformer Solutions' control boxes are designed to simplify maintenance, reduce field service time and enhance field changes. Our enclosures utilize IEC industrial-grade parts, readily available from stock at your local electrical distributor.
DIN rail mounting of circuit breakers, contactors and relays allows easy replacement and expandability; DIN-mounted sectional terminal blocks utilize captive screws and accept either bare wires or ring tongue terminals.
Well-organized wiring layout includes wire ducts and offers ample space for accessibility.
White painted cabinet interior and dual globe lights provide excellent illumination of all wiring and component areas.
GFCI-protected convenience outlet included as a standard feature.
SPX Transformer Solutions' exclusive PTC (Positive Temperature Coefficient) cabinet heater provides automatic uniform temperature regulation and condensation protection without the use of a thermostat.
Front door swings open to a minimum of 115 degrees and retains the open position during servicing using an automatic lock.
Exterior surfaces primed and painted to 3 mil thickness or greater.
All exposed hardware is stainless steel for corrosion-resistance.
Crowned roof prevents water accumulation, and a drip shield protects door hardware.
Standard enclosure meets Type 3R weatherproof rating; Type 4 and 4X rated enclosures are available as options.
De-Energized No-Load Tap Changer (DETC)
SPX Waukesha's de-energized tap changers are designed to last with no maintenance under normal operating conditions. The tap changer, a manually operated device, includes an external operating handle with a clearly marked position-indicating dial. Provisions are made for padlocking in each tap position and for the addition of key interlocks.
A Geneva drive is typically used to move the contacts to the correct position and also lock them in place for operation. Other benefits of the modular DETC include:
No coking on contacts
Ease of operation
due to simple design and few moving parts
No need to exercise switch
Easy contact replacement
Location flexibility within transformer
Ample ampacity and BIL
Meets IEEE PC57-131 and IEC 60214-1 test requirements
Moveable copper contacts fitted with multi-contact bands
Allows for reduction in tank size
UZD® On-Load Tap Changer (LTC) Waukesha's UZD® load tap changer is a field-proven design. When the minimally required maintenance is performed, UZD has a reliability rate of 99.95% for units built since 1997.
Designed for high speed, reliable operation and reduced maintenance, the UZD offers important features with benefits: BUE Motor Drive Mechanism
Charges the spring battery operating the load tap changer; housed separately in an air-filled compartment. Located at a convenient height and not in the oil-filled switching compartment. Readily accessible at ground level for inspections and maintenance.
Spring Drive Mechanism
Tap changer can be operated manually while energized and carrying load. Stored energy in the spring mechanism results in high speed operation and minimum arcing time. Each tap change is consistent and unaffected by voltage interruptions or manual hand cranking speed.
Power-Class Series Transformer/Booster
Series transformers reduce current levels passing through the contacts, thereby limiting arcing intensity and duration and extending LTC life. Power-class design means the series transformer used by SPX Transformer Solutions employs circular core/coil construction with disc or helical type windings.
Single Arm Design
Single arm simultaneously operates both the tap selector and arcing contacts for a simple basic design with few parts that helps reduce operating and maintenance costs.
Variety of Other Features
Designed to withstand full vacuum in tank without bypass piping to equalize pressure.
Large opening to tap changer compartment helps make inspections quick and easy while optional large viewing port permits inspection of contacts without removal of oil.
SPX Waukesha's design utilizes just three openings into the main transformer tank protected with O-ring gaskets for maximum protection from leaks—fewer openings means less maintenance.
Compact design requires only 110 gallons of oil to drain and replace.
Full-featured control compartment equipped to meet customer requirements.
Meets all requirements of IEEE standard for Load Tap Changers (IEEE C57.131-1995)
SPX Waukesha offers a wide range of accessories to enhance safety, reduce maintenance and monitor the performance of power transformers:
• Magnetic Oil Level Indicator
• High Voltage and Low Voltage Bushings
• Oil Temperature Indicator
• Hot Dipped Galvanized Radiators
• Drain Valve and Oil Sampling Valve
• Lifting Lugs on Tank (for lifting complete oil-filled transformer)
• Oversized Type 3R Control Box
• Lifting Lugs on Cover (for lifting cover only if necessary)
• Mechanical Pressure Relief Device
• Jacking Facilities at Each Corner of the Transformer Base
• Diagrammatic Aluminum Nameplate
• Fall Protection System
Optional • Multi-Ratio, Bushing-Type Current Transformers (CTs) for Relaying Service
• Surge Arresters
• Grounding Devices, such as reactors and resistors
• De-Energized Tap Changer (DETC)
• Load Tap Changers — Waukesha® UZD®, Reinhausen RMV-II, Etc.
• Conservator Oil Preservation Systems
• Stainless Steel Nameplates
• Various Monitoring Devices for Items such as Gas, Oil and Winding Temperatures; Power Factor and Moisture
• Most Customer Specified Accessories
• Transformer Health Products® :
The Waukesha® Component group, in Dallas, TX, manufactures a group of Transformer Health Products® designed to increase reliability and life of your transformer while lowering the cost of maintenance. Although branded together for the same end result, each of these components offers its own unique functionality
2nd Generation Nitrogen Generator
This product produces nitrogen from the air we breathe! SPX Waukesha's nitrogen generator provides a continuous (on-demand) source of pure, dry nitrogen to protect and maintain the nitrogen blanket on sealed transformer tanks. Notable features include the following:
Produces nitrogen at 120 psi instead of the traditional 3000 psi of a standard nitrogen cylinder; lower pressure means less system leaks
Maintains transformer tank pressure between 0.2 and 5.5 psi to protect transformer oil from oxidation and moisture absorption
Eliminates the need to transport and replace nitrogen bottles and the potential risk of maintenance personnel soft tissue injuries
Inert Air Systems
Using a standard nitrogen bottle, these positive pressure / regulated systems protect transformer oil in the main tank from oxidation and moisture absorption by keeping tank pressure at proper preset levels.
2nd Generation LTC Oil Filtration Systems
Our Retrofit and Retrofit-Plus systems install on most LTC models to remove carbon and metallic particles produced during normal operation, keeping oil in peak condition with minimal maintenance.
2nd Generation PTC Heater
Our Positive Temperature Coefficient (PTC) heater automatically maintains an enclosure temperature only slightly higher than the outside ambient temperature without using a thermostat or controls thereby protecting against heat damage and condensation.