QUALITY


Virginia Transformer’s vision statement underlies our attitude concerning quality. “To be an internationally recognized manufacturer and supplier of high quality specialized power transformers, and associated equipment, and services by fulfilling our commitments to the customer, our employees and stockholders through continued growth and improvement” VT views quality in three components – Quality a mind set, Process Control, and Testing.

Quality is an ongoing process and a mindset for all employees in the organization, no matter what level. From the customer perspective, it begins when they first have contact with us and does not end. To provide a level of understanding on how quality actually works at VT, here are some of the critical steps:

  • Sales order review and order entry
  • Engineering design review and verification
  • Vendor performance
  • Manufacturing check sheets
  • Shipping completeness and timeliness
  • Field service installation

Process


VT also controls quality through our process control:
  • Incoming materials inspection – a defined sampling plan and inspection control for components purchase, critical components tested in-house prior to assembly, and vendor performance monitored and evaluated
  • In-process – every process undergoes three levels of Quality Inspections
    • First stage – self inspection by operators using detailed in-process check sheets
    • Second stage – inspection and remedy by manufacturing technicians
    • Third stage – in-process audit checks and stage approval by QA
  • Final inspection – JB simulation check, finished transformer inspection, LTC and special components operation check, Ship separate parts inspection, and finish and fit inspection
Supporting our quality systems is our process verification which consists of:
  • Extensive internal audit program
  • All ISO elements covered during the year
  • In-depth audits of selective operations
  • Examines procedural compliance
  • Validates skill and knowledge application
  • Inspection moving toward audit

Testing


VTC has the ability to design, build and test transformers following international standards – ANSI, CSA, UL, IEC, and NEMA. During the manufacturing process, the following test can be performed on transformers as per relevant Standards:

  • Ratio/Phase relation test
  • Insulation power factor test
  • Excitation current test
  • Wind resistance test
  • No load loss and Excitation current test
  • Lighting impulse test
  • Applied voltage test (HIPOT)
  • Induced voltage dielectric test and RIV test
  • Audible sound level test
  • Oil PPM and Oil BDV tests prior to filling unit after ANSI tests
  • Zero sequence impedance test
  • Temperature rise test

In addition, VT can perform specialty tests mutually agreed upon with the customer:

  • DGA (Dissolved Gas Analysis)
  • Dew Poinr
  • TVA test
  • SFRA (Sweep Frequency Response Analysis)
  • Thermal Images
  • PD/RIV (Partial Discharge/Corona)
  • Switch impulse test
  • Front of wave impulse test
  • Fast front of wave switching impulse test