Quality Assurance
Quality System
Hebei Haihao Group operates an ISO 9001:2000 certified quality management system (since 2002, with predecessor ISO 9002 since 1999). Our flange and pipe fitting production lines hold ABS Type Approval since 2008. We are registered as a Safety Registration Enterprise for the manufacture of pressure pipe fittings.
Material Traceability
Every fitting and flange carries a heat number hard-stamp linked to:
- Mill Test Certificate of the finished item
- Mill Test Certificate of the mother material (for processed fittings: elbows, tees, reducers, caps)
- Heat treatment record (time-temperature curve, cooling rate)
- NDT report references (PT / MT / UT / RT as applicable)
- Hardness test results (mandatory for NACE / sour service items)
MTC default: EN 10204 type 3.1 — issued by our QA team, organizationally independent of production. Type 3.2 (countersigned by SGS / BV / TÜV / DNV / Lloyd's / Intertek) is available at additional cost.
Inspection Capabilities
Chemical Analysis
Spectrometer (PMI / OES) on every heat. Cross-check via wet chemistry on first article and random samples.
Mechanical Testing
- Tensile (Rm / Rp0.2 / elongation)
- Hardness: Brinell / Rockwell / Vickers (UCI for in-service spot checks)
- Charpy V-notch impact at -50°F / -100°F / -150°F as required (e.g. A420 WPL6 / WPL3 / WPL9)
Non-Destructive Testing (NDT)
- PT (liquid penetrant) — surface defects on stainless / non-magnetic
- MT (magnetic particle) — surface and near-surface on ferromagnetic
- UT (ultrasonic) — wall thickness, internal volumetric defects, weld interrogation
- RT (radiographic) — internal volumetric defects with permanent record
NDT operators certified to SNT-TC-1A or ISO 9712 Level II (Level III for RT).
Metallographic Examination
Microstructure analysis per ASTM E407 / ASTM E112 grain size. Available for grain size reporting and identification of heat treatment quality.
Heat Treatment
In-house furnaces with calibrated thermocouples (cal certificate < 12 months). Chart recorder operating on every furnace cycle. Standard treatments:
- Normalising — A234 / A105 / A350 LF2
- Normalising + tempering — A350 LF3 / A420 WPL6
- Quench + tempering — A234 WP91 / specialised alloy
- Solution annealing — A403 stainless / A790 duplex
- PWHT — A234 alloy after welding (1100-1250°F per A234)
Sour Service / NACE MR0175
For sour service:
- Hardness ≤ 187 HBW for A105 / A234 base material
- Normalising mandatory after forging
- HIC test per NACE TM0284 on plate-derived items (CLR ≤ 15% / CTR ≤ 5% / CSR ≤ 2%)
- Statement on MTC: "Material complies with NACE MR0175 / ISO 15156 requirements for sour service"
Pre-Shipment Inspection
Buyer or buyer's nominated TPI agency may witness inspection at our plant. Standard PSI agencies we work with: SGS, BV, TÜV Rheinland, DNV, Lloyd's, Intertek, ABS, Tüv Süd. PSI report is part of the document package released with the goods.
Continuous Improvement
- Internal audits twice yearly
- External ISO recertification annually
- Customer complaint / corrective action / preventive action (CAPA) workflow
- Training matrix for production, NDT, and QA personnel
Contact
QA department: haihaojituan@163.com | Tel: +86 132 9342 5333