Glossary of Quick Coupling

1. Coupling Design and Types

• Flat Face Coupling: A type of quick coupling with flat mating surfaces that minimizes fluid loss and air inclusion during connection and disconnection.
• Ball Lock Mechanism: A locking system that uses spring-loaded balls to securely connect the male and female coupling halves.
• Push-to-Connect: A mechanism that allows quick couplings to connect easily without requiring tools or excessive force.
• Shut-Off Valve: A valve inside a coupling that automatically closes to stop fluid flow when the coupling is disconnected.
• Single Shut-Off Coupling: A coupling where only one half (male or female) has a shut-off valve.
• Double Shut-Off Coupling: A coupling with valves on both the male and female halves, ensuring no fluid escapes during disconnection
• Dry Break Coupling: A specialized coupling designed to prevent fluid spillage and air inclusion during connection and disconnection.
• Non-Spill Coupling: A coupling designed to minimize or eliminate fluid spillage during disconnection.
• Modular Coupling: A quick coupling system with interchangeable components for versatile configurations.
• Multi-Coupling Plate: A system that connects multiple quick couplings simultaneously for hydraulic or pneumatic systems.
• Dry-Mate Coupling: A coupling specifically designed for no-spill and dry-break connections in hazardous environments.
• Wing Nut Coupling: A coupling that uses a wing nut for secure, tool-free connection and disconnection.
• Body Size: The nominal diameter of a quick coupling, usually expressed in inches or millimeters. Determines the flow capacity.
• Nominal Size: The approximate size of a coupling, often indicating its fluid flow capacity.
• Locking Mechanism: A feature (e.g., ball-lock, pin-lock) that secures the male and female parts together to prevent accidental disconnection.
• Sleeve: An external component of a coupling that operates the locking mechanism when slid or rotated.
• Latch: A locking mechanism used in some quick couplings to secure the connection.
• Locking Sleeve: The movable part of a coupling used to engage or disengage the locking mechanism.
• Vacuum Rating: The capacity of a coupling to function effectively in a vacuum or low-pressure environment.

2. Components and Features

• Locking Sleeve: The movable part of a coupling used to engage or disengage the locking mechanism.
• Captive Valve: A valve design that stays attached to the coupling body, reducing the risk of fluid spillage.
• Check Valve: A valve inside the quick coupling that prevents fluid flow when the coupling is disconnected.
• Poppet Valve: A valve type inside a coupling that opens when the coupling is connected and closes when disconnected.
• External Snap Ring: A retaining ring used to secure internal components of a quick coupling.
• Face Seal: A type of seal located on the mating surface of flat face couplings to ensure a leak-proof connection.
• Pull-Back Sleeve: A sleeve mechanism that requires pulling back to disconnect the coupling.
• O-ring: A circular sealing element used in quick couplings to prevent fluid leakage.
• Thread Sealant: A substance, such as PTFE tape or liquid sealant, applied to threads to ensure a leak-proof connection.

3. Materials and Coatings

• Stainless Steel Coupling: A corrosion-resistant coupling made from stainless steel, ideal for harsh environments and aggressive fluids.
• Zinc-Nickel Plating: A corrosion-resistant surface coating commonly applied to quick couplings for enhanced durability.
• Buna-N (Nitrile): A common elastomer used in seals for quick couplings, known for its oil resistance and affordability.
• Viton®: A brand name for a type of fluorocarbon elastomer used in seals, valued for its high chemical and heat resistance.
• Chemical Resistance: The ability of a coupling’s material to withstand exposure to specific chemicals without degradation.
• Elastomer: A flexible material, such as rubber, used in seals and O-rings within quick couplings.

4. Thread Types and Configurations

• NPT (National Pipe Thread): A thread standard commonly used in North America for pipe fittings, characterized by tapered threads.
• BSP (British Standard Pipe): A standardized thread type commonly used in Europe for hydraulic and pneumatic applications.
• G Thread: A parallel-thread standard for pipe connections, commonly used in Europe and Asia.
• End Configuration: The specific type of connection (e.g., NPT, BSPP, flanged, or welded) on the coupling for attaching to hoses or pipes.
• Female Thread: The internal thread on the coupling or adapter used for connection.
• Male Thread: The external thread on the coupling or adapter used for connection.
• Thread Size: The nominal dimension of the thread, often labeled as NPT, BSP, or G (e.g., 1/4″, 3/8″).

5. Performance and Ratings

• Working Pressure: The maximum pressure at which a coupling can safely operate continuously.
• Pressure Rating: The maximum pressure a coupling can handle, typically expressed in bar or PSI (pounds per square inch).
• Burst Pressure: The pressure at which a coupling will fail or rupture, typically much higher than the working pressure.
• Pressure Drop: The reduction in fluid pressure as it flows through the coupling, often influenced by the internal design.
• Residual Pressure: The pressure remaining in a disconnected hydraulic line or coupling.
• Flow Rate: The amount of fluid that passes through the coupling in a given period, typically measured in liters per minute (LPM) or gallons per minute (GPM).
• Heat Resistance: The ability of a coupling’s material to withstand high temperatures without degrading.
• Vibration Resistance: The ability of a coupling to stay securely connected under vibrations or dynamic loads.
• Wear Resistance: The ability of a coupling’s material to withstand wear and tear during prolonged use.
• Operating Temperature Range: The temperature range within which the coupling is designed to function safely and efficiently.
• Torque Rating: The maximum twisting force that can be applied to the coupling threads without causing damage.

6. Safety and Protection

• Breakaway Coupling: A safety coupling designed to disconnect automatically when excessive force or pull is applied, preventing damage to equipment.
• Safety Coupling: A coupling designed with features to prevent accidental disconnection or pressure bursts.
• Blow-Off Valve: A safety feature designed to release pressure in a hydraulic line before disconnection.
• Dust Cap/Dust Plug: Protective covers placed on the male and female ends of a coupling to prevent contamination and damage when not in use.

7. Specialized Features

• Self-Sealing Coupling: A coupling with automatic shut-off features to minimize spillage.
• Spill-Resistant Coupling: A coupling designed to minimize fluid leakage during connection and disconnection.
• Pressure Compensated Coupling: A coupling designed to handle high residual pressure during connection.
• Non-Return Valve: A valve that allows fluid to flow in one direction only, often built into a quick coupling.

8. Accessories

• Coupling Set: A complete quick coupling assembly that includes both the male and female halves.
• Male Coupler (Plug): The part of a quick coupling that is inserted into the female coupler.
• Socket (Female Coupler): The female half of a quick coupling into which the male plug fits.
• Coupling Half: One side of a quick coupling (either male or female) before being connected.
• Double Shut-Off Coupling: A coupling with valves on both the male and female halves, ensuring no fluid escapes during disconnection.
• Y-Splitter: An accessory that allows one fluid line to split into two, often using quick couplings.

9. Standards and Compatibility

• ISO Standards: International standards (e.g., ISO 7241, ISO 5675, ISO 16028) that define dimensions, performance, and interchangeability of quick couplings.
• Parker Profile: A specific design or configuration of a quick coupling developed by Parker Hannifin, often used as a reference for compatibility.
• Interchangeable Coupling: A coupling designed to connect with couplings from other manufacturers that meet the same standard (e.g., ISO 7241-1 Series A).

10. Applications and Usage

• High-Cycle Coupling: A coupling designed to endure frequent connection and disconnection cycles.
• Hydraulic Coupling: A quick coupling designed for hydraulic systems, capable of handling high pressures.
• Pilot Line Coupling: A coupling designed for small hydraulic lines that control larger valves or systems.
• Vacuum Coupling: A coupling designed for systems operating under vacuum conditions.
• Zero Inclusion Coupling: A coupling designed to prevent any air or fluid mixing during connection and disconnection.

11.others

• Quick Disconnect: Another term for quick coupling, emphasizing the ease of disconnection.
• Flow Restriction: The reduction in fluid flow caused by the internal geometry of the coupling.
• Quick Release Coupling: Another term for quick coupling, emphasizing the ease of connection and disconnection.
• Air Inclusion: The amount of air that enters the hydraulic system during connection or disconnection of a quick coupling.