Built-for-duty welding that protects people, assets, and uptime
Power plants run under extreme temperatures, pressures, and cycles. That’s why every joint must be engineered, executed, and documented with zero guesswork. Bunney’s Inc. delivers precision welding for power plants—from boilers and high-energy piping to turbines and balance-of-plant systems—serving owners and EPCs across Arizona with code-aligned procedures, trained crews, and inspection-ready records.
New to Bunney’s? Learn who we are and explore our capabilities.
What “precision welding” means in a power plant
Precision welding is the controlled joining of metals to strict procedure and quality criteria. In practice, it combines:
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Defined procedures: WPS/PQR/WPQ to ASME Section IX (and AWS where applicable)
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Process discipline: GTAW, SMAW, FCAW/GMAW, orbital tube/pipe, purge and interpass controls
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Material stewardship: Carbon/low-alloy steels (e.g., P11/P22/P91), stainless, duplex, and nickel alloys
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Verification: NDE to ASME Section V (PT/MT/UT/RT), PMI, hardness checks, pressure/leak tests
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Traceability: Heat/lot control, weld mapping, calibrated instrumentation, and complete turnover packages
Typical applications we support
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Boilers & pressure parts: Tube panels, headers, drums, seal welds, attemperator and superheater connections
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High-energy piping (HEP): Main steam, hot reheat, cold reheat, feedwater, and auxiliary steam systems
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Turbine islands: Casing repairs, diffuser and extraction lines, stainless/nickel connections
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Balance of plant: Condensers, cooling water, chillers, heat-exchanger shells, tanks, sumps, and supports
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Nuclear scopes (as applicable): Safety-related stainless/nickel work, radwaste tie-ins, outage repairs (planned with authorized partners when code stamps are required)
Why precision welding matters
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Safety & compliance: Code-based joints reduce leak, rupture, and personnel risk
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Reliability: Controlled heat input and metallurgy mitigate creep, fatigue, and stress-corrosion cracking
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Efficiency: Sound welds maintain pressure/temperature integrity and unit heat rate
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Lower lifecycle cost: Less rework, fewer forced outages, longer intervals between repairs
Our Arizona-ready execution model
Arizona’s heat, dust, and monsoon swings call for tight controls. We build those in:
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Plan & pre-fabricate: Laser-accurate field dimensions, shop spools, fit-up mockups to compress outage hours
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Environmental control: Shade/evaporation control for summer work; humidity and dust mitigation during monsoon season
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Metallurgy management: Preheat/interpass control, PWHT coordination, purge quality for stainless/nickel
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ALARA/safety: Radiological work packaged to minimize time/dose; lockout/tagout, confined space, hot-work permitting
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Inspection readiness: Hold points, owner/AI witness, and clean, cross-checked data books at turnover
What you receive from Bunney’s Inc.
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Validated procedures & people: WPS/PQR/WPQ matched to your alloys, thicknesses, and positions
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Transparent QA/QC: Weld maps, ITPs, consumable control, calibrated tools, and NDE reports
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Clear documentation: CMTRs/PMI, heat traceability, pressure-test records, nonconformance/CAR logs, final data package
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Schedule discipline: Sequenced work packs, shift plans, and progress reporting aligned to outage windows
Note: Where ASME Section III or National Board scope applies, we coordinate with appropriately authorized certificate holders to protect code status and documentation.
How to choose a power-plant welding partner (quick checklist)
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Documented QA program (Appendix B/NQA-1 when nuclear is in scope)
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Proven Section IX depth in your alloys (e.g., P91) and joint types
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In-house/partner Section V NDE with clear acceptance criteria
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Sample redacted data book with weld maps and traceability
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Outage KPIs: schedule adherence, ALARA results (if nuclear), rework rate, safety record
FAQs
What code(s) govern power-plant welding?
Most fossil and combined-cycle scopes reference ASME Section IX for qualifications and ASME Section V for NDE; pressure parts may also invoke ASME Section I/VIII. Nuclear work adds ASME Section III, 10 CFR 50 Appendix B, and often NQA-1.
How do you handle P91 and other creep-strength alloys?
With qualified procedures controlling preheat, interpass, and PWHT; verified filler metals; hardness checks; and tight heat input to protect microstructure.
When is orbital welding a better choice?
For small-diameter tube/pipe where repeatability, purge quality, and tight access make mechanized GTAW more reliable than manual welds.
What NDE methods are typical?
PT/MT for surface flaws, UT/PAUT or RT for volumetric examination, plus PMI and hardness testing where required by spec.
Can you work during live operations?
Yes—scopes are planned with hot-work permits, isolation plans, access control, and owner approvals to protect people and production.
What’s included in the turnover package?
WPS/PQR/WPQ sets, weld maps, CMTRs/PMI, ITPs/hold points, NDE and pressure-test results, calibration lists, and final release/closeout.
How far in advance should we engage you for an outage?
Ideally 6–12+ weeks to finalize procedures, procure materials, complete pre-fab, and align inspection/test plans.
Do you support emergency repairs?
Yes—expedited mobilization is available; we’ll align risks, scope, and temporary/permanent repair strategies with your engineering team.
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