Service
ISO 3834-2 certified welding and fabrication
Fusion welding of pressure vessels, pressure piping, boilers, heat exchangers, tanks and structural steel under a quality system certified to ISO 3834-2:2021, with ASME IX qualified procedures and welders.
ISO 3834-2 is the comprehensive quality requirement for fusion welding: it certifies that a fabricator’s procedures, welders, coordination, equipment, materials control and inspection are managed as a system, not just that a weld passed a test. Umbusso Engineers’ welding quality system is certified to ISO 3834-2:2021 by JC Auditors (certificate 1013, valid 7 April 2026 to 6 April 2029) at our fabrication workshop at 1945 York Road, Evander.
The certified scope covers pressure vessels, pressure piping and equipment, heaters and boilers, heat exchangers, tanks, sheet metal and structural steel, with construction standards including ASME VIII, ASME B31.1 and B31.3, PD 5500, EN 13445, EN 13480, EN 12952, API 620, 650 and 653, and AWS D1.1, D1.3 and D1.6. Welding is carried out to ASME IX procedure specifications qualified in September 2025 for carbon steel, chromium-molybdenum and austenitic stainless base metals, by welders holding current ASME IX performance qualifications, under a named welding coordinator.
What we do
- Pressure piping spools and headers in carbon, chrome-moly and stainless steel.
- Pressure vessel, heat exchanger and tank fabrication and repair within the certified scope.
- Boiler and heater pressure-part welding and repair to the applicable code.
- Structural steel welding to AWS D1.1 and sheet-metal work to D1.3 and D1.6.
- Site welding under the same procedures, coordination and inspection as the workshop.
- Welding procedure development and qualification for client-specific materials.
Standards, quality and documentation
Processes: shielded metal arc (111), gas tungsten arc (141) and gas metal arc (135). Material groups 1, 5, 8 and 11 under ISO 15608 — carbon and low-alloy steels, creep-resisting steels and austenitic stainless steels. Welding coordination is provided by a coordinator with specific technical knowledge per the certificate schedule, with IWE/IWT support available by subcontract. Every fabrication order is released against a quality control plan with client hold points, and weld inspection and pressure testing follow the project inspection and test plan.
Where this service applies on the plant
Explore the representative plant environment in the Umbusso Industrial World to see the equipment this service covers.
Proof: work delivered on purchase order
Each project record states the client, the order or contract reference, the scope and the quality documentation it ran under. Contract values are available to prospective clients on request.
Slurry plant rubber lining
Replacement and internal rubber lining of the AWRSE tank outlet pipework to slurry Mixers A, B and C, and rubber lining of the slurry plant mixers, delivered as Main Contractor with a full data book.
Eskom Holdings SOC Ltd · 2025–2026
Read the project record →Water-tank structural work
Installation and modification of structural steel beams inside a water tank, with scaffolding, under confined-space controls.
Eskom Holdings SOC Ltd (under the main contractor) · 2022
Read the project record →Conveyor pulley manufacture
Eighteen conveyor pulleys manufactured to Eskom drawing under a quality control plan counter-signed by Eskom Quality Assurance before manufacture began, together with bearings, pillow blocks, idler frames and drive components.
Eskom Holdings SOC Ltd · 2024–2025
Read the project record →From the workshop and site
How an order runs
Send the drawing, scope or problem. We reply with questions or a site-visit date.
We confirm the scope, access, outage window and your quality and safety requirements.
Priced quotation with a quality control plan outline so the hold points are agreed before award.
Work under permit-to-work and the agreed plan, with witnessed hold points and progress reporting.
Inspection records, certificates and material traceability compiled into the data book and handed over.
Frequently asked
What does ISO 3834-2 certification actually give a plant owner?
Assurance that welding is controlled as a system: qualified procedures, qualified welders, a named coordinator, calibrated equipment, material control and inspection. It is the level most pressure-equipment and generation-site tenders ask for.
Which welding procedures are qualified?
ASME IX procedure specifications and qualification records for P-No. 1 carbon steel, P-No. 5 chromium-molybdenum and P-No. 8 austenitic stainless steel, including SMAW and GTAW combinations, signed 17 September 2025.
Can we see the certificate?
Yes — it is published on our Certifications page with the certificate number and can be verified with the issuing body.
Technical articles on this equipment
Written and reviewed in-house. What fails, why it fails, what the standards require and how to specify the repair.
What ISO 3834-2 and ASME IX qualification mean for a plant owner buying pipe welding
“Coded welding” is often claimed and rarely explained. This article explains what a plant owner is actually buying when a fabricator holds ISO 3834-2 certification and ASME IX qualified procedures and welders, and what to ask for on the next piping order.
Reviewed by the Welding Coordinator · September 2026
Read the article →Corrosion, section loss and connection failure on plant structures: inspection and repair scopes
Plant structures are inspected less often than the equipment they carry, and they fail slowly until they fail suddenly. This article sets out where corrosion and connection failure start, how to inspect for them, and how a repair scope is defined so it can be priced and executed inside an outage.
Reviewed by the Welding Coordinator · September 2026
Read the article →Related services
Request a quotation
Send us the drawing, the scope or the problem. We reply with questions, a site-visit date or a priced quotation — whichever gets you an answer fastest.
Office +27 17 007 0135 · WhatsApp +27 72 535 1598 · info@umbussoengineers.co.za
