The Siam Industrial Wire Co. Ltd

The Siam Industrial Wire Co. Ltd is a leading manufacturer and testing service provider for prestressed concrete steel products, headquartered in Bangkok, Thailand. Established in 1974 and now a subsidiary of Tata Steel Group through NatSteel Holdings, SIW is one of ASEAN's largest producers of pre-stressed concrete strand, wire, and related steel products, with annual production exceeding 200,000 tonnes. The company operates both manufacturing facilities and a dedicated testing service center specializing in quality assurance for prestressed steel wire and PC strand applications.

SIW's Testing Service Center provides comprehensive quality testing for prestressed steel wire and PC strand products, serving manufacturers and end-users who require certified test results conforming to international standards. The laboratory is ISO/IEC 17025 accredited by NATA (National Association of Testing Authorities, Australia), ensuring independent, unbiased testing and reliable assessment of material performance. With over 30 years of specialized expertise in prestressed concrete steel testing, the facility maintains modern, high-efficiency equipment with precision exceeding 99.95%.

The testing center offers a full range of mechanical property testing services for prestressed steel products. Primary services include tensile testing with VDO extensometer for accurate elongation measurement, fatigue testing using specialized equipment to determine stress-cycle performance and fatigue life prediction, and stress-relaxation testing with extensometer monitoring for measuring force loss over time under sustained load. The laboratory operates a Fatigue Testing Machine (Zwick Roell Model HA500) with maximum load capacity of 500 kN, capable of supporting advanced cyclic stress analysis. Additionally, the facility provides salt spray corrosion testing and chemical composition analysis of steel samples.

The laboratory supports testing compliance with multiple national and international standards including AS/NZS 4672.1, AS/NZS 4672.2 (Australian/New Zealand prestressed concrete strand standards), BS 5896 (British Standard for high-tensile steel wire for prestressed concrete), LNEC E 542 and LNEC E 453 (Portuguese standards for concrete reinforcement), ISO 15630 Part 3 (steel reinforcement products), and Thai standards TIS 95-2540 and TIS 420-2540. This breadth of standard coverage enables SIW to serve both domestic Thai markets and international projects requiring compliance with diverse regulatory frameworks.

The primary industries served are construction and infrastructure development, particularly those utilizing prestressed concrete technology. SIW's testing center supports the prestressed concrete product supply chain, including manufacturers of PC strand and wire, precast concrete manufacturers, and construction contractors executing large-scale projects. The company's products and testing services have been applied to major infrastructure projects including Thailand's Motorway M6 and international bridge and foundation work. The facility also serves the concrete reinforcement industry, providing material certification and quality verification for projects where prestressed steel performance is critical to structural safety and durability.

SIW maintains quality management systems and operational standards appropriate to a technical testing laboratory serving structural applications in the construction industry. The company received the 2022 Excellent Practices Establishment Award, reflecting commitment to quality and operational excellence. Testing reports provided by the laboratory include detailed analysis with traceable documentation at each testing stage, improvement suggestions based on results, and flexible customization of testing protocols to meet specific client requirements. The facility's combination of modern equipment, expert technical personnel, and ISO 17025 accreditation positions it as a credible partner for testing and certification of prestressed concrete steel products in both regional and international markets.