ISO 8140:2018

Overview

ISO 8140:2018 specifies the mounting dimensions of rod-end clevises for pneumatic fluid power cylinders operating at 1,000 kPa (10 bar). These rod-end clevises ensure interchangeability across pneumatic cylinders, supporting standardized mechanical connections essential for reliable transmission of force. Primarily designed for use with cylinders conforming to ISO 6432 and ISO 15552, this standard applies universally to pneumatic cylinders within the 10 bar pressure series, facilitating consistent and safe installation of components.

The standard focuses on the dimensional requirements needed for clevises mounted on piston rods. It accounts for maximum forces derived from cylinder internal diameter and pressure conditions, promoting safety and compatibility in pneumatic systems.

Key Topics

• Interchangeability dimensions: Defines exact mounting sizes for rod-end clevises to guarantee compatibility with cylinders from multiple manufacturers.
• Applicable cylinder series: Specifically targets 1,000 kPa (10 bar) pneumatic cylinders made according to ISO 6432 (small bore) and ISO 15552 (larger bore) standards.
• Design considerations: Clevises are engineered to withstand forces based on cylinder diameters and pressures set by ISO 6432, ISO 15552, and ISO 21287 (compact cylinders).
• Installation guidelines: Recommends tolerance classes (f8 per ISO 286-2) for shafts, use of locking nuts for secure assembly, and lubrication practices to maintain performance.
• Dimension tables and figures: Provides precise metrics, including thread sizes (M4 to M48), bore diameters, length parameters, and tolerances to simplify component selection.
• Validation and conformity: Encourages manufacturers to declare compliance with ISO 8140:2018 for better market transparency and quality assurance.

Applications

ISO 8140:2018 serves a critical role in pneumatic fluid power systems across various industries, including:

• Industrial automation: Ensures standardized rod-end clevis fittings for pneumatic cylinders used in manufacturing lines, robotic arms, and conveyor actuators.
• Automotive assembly: Supports consistent cylinder mounting in pneumatic tooling and clamping solutions.
• Material handling: Facilitates secure attachment of rod-end clevises in pneumatic lifts, grippers, and positioners.
• Packaging and processing: Guarantees reliable mechanical force transmission through compliant clevis mounting on actuators.
• General mechanical engineering: Offers universal machining and assembly guidelines for cylinder rod-end clevises, improving maintenance and replacement workflows.

By adhering to ISO 8140:2018, equipment manufacturers and system integrators benefit from enhanced interchangeability, reduced downtime, and improved safety in pneumatic actuation setups.

Related Standards

ISO 8140 references and complements several key international standards for pneumatic cylinders and components:

• ISO 6432: Pneumatic cylinders series 1,000 kPa (10 bar) with bore sizes from 8 mm to 25 mm - fundamental base and mounting dimensions.
• ISO 15552: Pneumatic cylinders with detachable mountings for 1,000 kPa (10 bar), bore sizes 32 mm to 320 mm - specification of base dimensions and accessories.
• ISO 21287: Compact pneumatic cylinders for 1,000 kPa (10 bar) - dimensions for compact actuator designs.
• ISO 6099: Code for identifying mounting dimensions and fixation methods of pneumatic cylinders, directly integrated into ISO 8140 for clevis dimension coding.
• ISO 5598: Vocabulary of terms used across hydraulic and pneumatic transmissions, ensuring clear and uniform technical language.
• ISO 286-2: Geometrical product specifications for tolerance classes, referenced for shaft-tolerance recommendations in clevis installation.

These standards work together to form a cohesive framework for pneumatic cylinder design, manufacturing, and application, providing engineers and manufacturers with a common technical foundation.

Keywords: ISO 8140, pneumatic fluid power, pneumatic cylinders, rod-end clevises, mounting dimensions, 10 bar pneumatic cylinders, ISO 6432, ISO 15552, standardized clevis, pneumatic actuator components, cylinder rod-end fittings, pneumatic system design, interchangeability, industrial automation standards.