ISO 10434:2020

Overview

ISO 10434:2020 specifies requirements for bolted bonnet steel gate valves intended for the petroleum, petrochemical and allied industries. The standard defines a heavy‑duty series of valves designed for refinery and related service conditions where corrosion, erosion or demanding process conditions require full‑port openings, heavy wall sections and large stem diameters. ISO 10434:2020 aligns with common industry practice (parallel to API 600) and covers flanged and butt‑welding end constructions across a wide range of sizes and pressure ratings.

Key topics and technical requirements

The standard sets out technical requirements and tests for gate valves with features including:

• Construction type: bolted bonnet; outside screw and yoke.
• Actuation/operation: rising stems and non‑rising handwheels.
• Gate options: single or double gate; wedge or parallel seating; metallic seating surfaces.
• End connections: flanged or butt‑welding ends.
• Sizes and ratings: nominal sizes DN 25 to DN 600 (NPS 1 to 24); Class ratings 150–2,500 and PN ratings 16–400 as applicable.
• Design details: body and bonnet wall thicknesses, body dimensions, bonnet‑to‑body joint, gate, yoke, stem and stem nut design, packing and bolting requirements.
• Materials and fabrication: base materials, trim material options, and welding qualifications for fabrication and repair.
• Testing and inspection: shell tests, closure tightness tests, optional backseat/closure tests, fugitive emission testing (reference to ISO 15848), plus inspection and examination requirements.
• Marking and documentation: requirements for legible body/ring/plate marking and purchaser‑specified information (Annex A).

Practical applications and who uses this standard

ISO 10434:2020 is used by:

• Valve manufacturers designing and fabricating heavy‑duty gate valves for refinery and petrochemical service.
• Process, mechanical and piping engineers specifying valves for critical hydrocarbon service where full port flow and robust construction are required.
• Procurement and quality assurance teams who need standardized acceptance criteria, testing protocols and marking for tenders and inspections.
• Inspection bodies and plant operators verifying compliance, pressure/temperature ratings and fugitive emission performance.

Typical applications include refinery process lines, crude and product transfer, high‑erosion or high‑temperature service and other demanding industrial piping systems.

Related standards

ISO 10434 references and works alongside international standards such as:

• ISO 5208 (pressure testing of metallic valves)
• ISO 15848‑1/2 (fugitive emissions)
• ISO 5752 (face‑to‑face dimensions)
• ASME B16.34 (valves - flanged, threaded and welding ends)
• API Standard 600 (comparable gate valve practice)

Using ISO 10434:2020 helps ensure consistent, auditable requirements for heavy‑duty bolted bonnet gate valves in petroleum and petrochemical environments.