Custom Duplex & Super Duplex Pipe Spools for Corrosive Process Piping

PETROL STEEL offers custom-made Duplex and Super Duplex pipe spools for corrosive process piping, offshore and sour-service systems, petrochemical facilities, mining and hydrometallurgy, seawater systems, and desalination projects. Spool fabrication from DN15 to DN1800 (1/2″–72″) is available in materials F51 (UNS S31803), F60 (UNS S32205), F53 (UNS S32750), and F55 (UNS S32760) as per project isometric drawings and transport requirements.

Fabrication scope includes CNC and coping cutting, automatic beveling, fit-up and tack welding, manual/orbital/mechanized TIG/GTAW, narrow-groove welding for heavy wall sections, solution heat treatment, and PWHT as specified. Inspection can include 100% visual and dimensional inspection, RT/UT/PT/MT, PMI by heat, ferrite measurement, hardness testing for NACE-governed service, and EN 10204 3.1/3.2 documentation.

Custom Duplex & Super Duplex Pipe Spools for EPC Projects

Duplex and Super Duplex pipe spools are chosen for a project when a combination of corrosion resistance, mechanical strength, and controlled fabrication performance is needed, which conventional stainless steel may not be able to provide for the specified service. In seawater, chemical processing, and other chloride-bearing environments in offshore oil and gas, the selection of materials and control of welding are closely related to long-term piping performance. Recent industry applications include offshore systems, seawater cooling and firewater, high-pressure seawater and brine piping, desalination, and chemical processing.

“PETROL STEEL manufactures fabricated spools rather than treating pipe, fittings, and flanges as separate catalog items. Each spool can be prepared from project isometric drawings and coordinated around required dimensions, connection points, fabrication sequence, and transport envelope. The material scope includes Duplex F51/S31803, Duplex F60/S32205, Super Duplex F53/S32750, and Super Duplex F55/S32760. Standard diameter capability is DN15 to DN1800 (1/2”–72”). The spool length is customized according to the project drawing and transportation requirements.

For EPC engineers, one of the key issues is not whether a supplier can weld Duplex stainless steel but whether the whole fabrication process can be controlled and documented. The scope of PETROL STEEL includes cutting, beveling, fit-up, TIG/GTAW welding, narrow groove welding for heavy wall sections, solution treatment and PWHT as required, dimensional inspection, NDT, PMI, ferrite measurement, and material traceability. This becomes even more important for projects where the welding procedure qualification, heat treatment, ferrite balance, inspection hold points, and material documentation have to be verified before shipment. The technical requirements are verified against the relevant project specification and are not replaced by a generic catalog specification.

Materials, Fabrication, and Project Capability

The available Duplex and Super Duplex grades are developed for project-specific service conditions, not for one-size-fits-all. F51 (UNS S31803) and F60 (UNS S32205) meet common Duplex specifications, with F53 (UNS S32750) and F55 (UNS S32760) available for Super Duplex applications. The actual material selection is still dependent on the process medium, chloride content, temperature, pressure, design code, and the project material specification.

We can produce from customer-provided isometric drawings, piping layouts, BOMs, and project specifications. CNC cutting of spools, pipe-intersection/coping cutting, and automatic beveling. Followed by fit-up and manual, orbital, or mechanized TIG/GTAW welding. GTAW for narrow grooves can be applied to suitable heavy wall joints. Solution heat treatment and PWHT can be arranged where required by the project specification, with support for full section heat treatment for sections up to 13 m furnace length.

Quality Control, Inspection, and Traceability

Quality documentation in international EPC projects is a product supply and not an afterthought. PETROL STEEL undertakes internal QC inspection on every Custom Duplex & Super Duplex Pipe Spool and facilitates Third Party Inspection as per project requirements. Visual and dimensional inspection, applicable NDT, PMI verification by heat, ferrite content measurement, and hardness test for NACE service can be part of the inspection.

Material and inspection records are maintained, and where applicable, EN 10204 3.1 / 3.2 certification is available. The corrosion-resistant surface can be identified by laser marking without being damaged. Export packaging includes flange face protection, individual wrapping, and plywood cases/crates with package identification and packing list matching international shipment.

For over 10 years, PETROL STEEL has been an exporter of Custom Duplex & Super Duplex Pipe Spools. The company has a technical team with over 10 years of experience in the industry, an international trade and marketing team with more than 20 years of experience, a QC team with over 10 years of experience, and a logistics team with over 15 years of experience to support the projects. The teams coordinate the technical review, the commercial communication, the inspection documentation, the shipment preparation, and the after-sales support for each order. PETROL STEEL’s quality commitment is to combine internal QC and third-party inspection to ensure each supplied spool is checked against the confirmed project requirements. The company states that, based on its stated export record, it has no product or service claim cases in this product category.

Lead Time and International Supply

Custom Duplex & Super Duplex Pipe Spools typically have a lead time of 3-5 weeks for standard orders, subject to confirmed material availability, spool complexity, quantity, inspection requirements, and project documentation. Review and confirmation of final delivery, technical and commercial.

PETROL STEEL can manage the supply process from the drawing review and material confirmation to fabrication, inspection, documentation, export packing, and international transportation for international EPC procurement. No obligation exists to submit a completed specification package before contact; an isometric drawing, material specification, BOM, or RFQ can be used as the basis for a technical review.

What to Include in Your RFQ

EPC engineers and project buyers are encouraged to provide the following to reduce quotation lead times and avoid gaps in specifications:

Material grade: F51/S31803, F60/S32205, F53/S32750, F55/S32760

Pipe/spool size: nominal pipe diameter and thickness

Quantity: number of spools, total length, or estimated weight, if applicable

Isometric drawings: PDF, DWG, or other format available for the project

Piping specification: Project piping class or material specification, whichever applies

Welding requirements: WPS/PQR, welding process, or project specification where applicable.

Inspection requirements: NDT, PMI, ferrite measurement, hardness testing, and third-party inspection requirements

Applicable standards/codes, certification requirements, and project-specific requirements

Documentation: MTC, EN 10204 3.1/3.2, inspection records, and other QA/QC documents as required

Delivery location: country/port of destination and required delivery date.

Why Work with PETROL STEEL?

PETROL STEEL is not into commodity stainless steel trading but into industrial piping and EPC project supply. For Duplex and Super Duplex Pipe Spool projects, the focus is on matching the confirmed material specification, fabrication requirements, inspection plan, documentation, and delivery conditions prior to production commencement.

The company offers long-term international export experience combined with dedicated technical, commercial, QC, and logistics support. This approach allows PETROL STEEL to assist buyers who need more than a material price—in particular EPC contractors, engineering procurement teams, project buyers, importers, and industrial piping contractors that require fabricated spools ready for project installation.

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