SIST EN ISO 14691:2009 PDF

Overview

EN ISO 14691:2008 / ISO 14691:2008 defines requirements for flexible couplings used in mechanical power transmission for the petroleum, petrochemical and natural gas industries. The standard covers couplings intended for general-purpose applications, typically up to 4 000 r/min, where the coupled machines are stiff-shaft (the first lateral critical speed is above the running speed). It applies to couplings that accommodate parallel offset, angular misalignment and axial displacement without imposing excessive loads on connected equipment. The standard has been adopted by CEN as EN ISO 14691:2008.

Key topics and technical requirements

• Scope and applicability: General-purpose couplings (gear, metallic flexible-element, elastomeric, composite components) and methods of attachment (including tapered sleeves and proprietary devices).
• Excluded types: Not applicable to clutch, hydraulic, eddy-current, rigid and radial-spline couplings.
• Design and construction: Requirements for materials of construction, coupling hubs, bolting and electrical insulation.
• Coupling rating: Criteria for rating and required vendor/purchaser data to define duty.
• Alignment and rotor dynamics: Provision for alignment, rotor dynamic data and handling of non-horizontal installations.
• Balancing: Balance objectives, balance quality classes and verification/testing of coupling balance.
• Inspection, testing and manufacturing: Manufacturing quality, inspection and test requirements, plus preparation for shipment.
• Accessories and guards: Guidance on accessories and coupling guards (Annex D) and recommended datasheet content (Annex E).
• Vendor / purchaser responsibilities: Specifies purchaser’s specification items and vendor data to be supplied.

Practical applications

• Selection and procurement of flexible couplings for pumps, compressors, turbines and drivers in onshore and offshore oil & gas facilities.
• Engineering design checks where misalignment accommodation, mechanical loading limits and balance quality are critical.
• Quality assurance, acceptance testing and factory inspection of couplings supplied for rotating equipment.
• Maintenance planning and replacement specification for coupling upgrades or retrofits.

Who should use this standard

• Mechanical and rotating-equipment engineers in the petroleum, petrochemical and natural gas sectors
• Equipment manufacturers and coupling vendors
• Procurement, inspection and maintenance teams specifying acceptance criteria
• OEMs and integrators preparing datasheets and technical contracts

Related standards

• ISO 10441 - recommended for special-purpose, high-speed or rotor-dynamics-sensitive applications (flexible-shaft machines).
• ISO 286-2 - limits and fits referenced for dimensional tolerances.

By applying EN ISO 14691:2008, stakeholders ensure consistent design, testing and documentation for flexible couplings used in typical oil & gas rotating machinery, improving reliability and simplifying procurement and compliance.