EN 61518:2001

Overview

EN 61518:2001 (CLC adoption of IEC 61518:2001, including Corrigendum Feb 2002) specifies the mating dimensions between differential pressure (type) measuring instruments and flanged‑on shut‑off devices (manifolds) for service up to 413 bar (41.3 MPa). The standard applies where a differential‑pressure instrument is fitted with a shut‑off device that is directly bolted to the instrument, defining the mechanical interface to ensure interchangeability and safe operation.

Key topics and requirements

• Scope and applicability: Defines the interface limits for differential pressure measuring instruments with flanged‑on shut‑off devices up to 413 bar.
• Mating dimensions: Specifies the geometric relationships and dimensional requirements for the instrument/manifold mating surfaces to ensure correct fit‑up and alignment.
• Flange interface features: Covers flange faces, bolt‑hole patterns and position relationships necessary for direct bolting of shut‑off devices to instruments (pressure class up to 413 bar).
• Compatibility and interchangeability: Ensures instruments and manifolds from different manufacturers will mechanically mate when built to the standard.
• Mounting and sealing considerations: Addresses the interface features that affect sealing performance and mechanical load transfer (e.g., alignment, contact surfaces).
• Reference to corrigendum: Incorporates amendments published in the February 2002 corrigendum to IEC 61518:2001.

(Note: EN 61518:2001 defines mechanical interface requirements; it does not replace detailed pressure‑rating, material selection, or local installation rules.)

Applications

• Instrument manufacturers and manifold (shut‑off device) designers use EN 61518 to design mechanical interfaces that are interchangeable across suppliers.
• Process and instrumentation engineers in oil & gas, petrochemical, power generation, and industrial process control use the standard to specify compatible differential pressure transmitters and manifolds for high‑pressure service (up to 413 bar).
• Procurement and maintenance teams rely on the standard to ensure replacement parts and retrofits will fit without custom machining or modification.
• Calibration and test laboratories benefit from consistent mounting interfaces for reliable test setups.

Related standards

• IEC 61518:2001 (original international publication) - identical technical content.
• Corrigendum IEC 61518 (Feb 2002) - incorporated corrections.
• Complementary standards may cover pressure instrument performance, process connections and flange design (refer to applicable ISO/ASME or industry specifications for pressure ratings, materials and testing).

Keywords: EN 61518:2001, IEC 61518, mating dimensions, differential pressure measuring instruments, flanged‑on shut‑off devices, manifold, 413 bar, instrument‑manifold compatibility, pressure instrumentation standard.