What are Hydraulic Quick Couplers and How Do They Work?

Hydraulic quick couplers facilitate the quick connection and disconnection of fluid lines in a quick and convenient way. Quick disconnect couplings are fittings that are used in hydraulic and pneumatic systems to quickly connect and disconnect lines without loss of fluid or pressure. Hydraulic quick couplings give operators the ability to quickly connect and disconnect hydraulic lines to various types of machinery, equipment, and attachments.

Quick Connect and Disconnect without Additional Tools

Hydraulic quick couplers are designed for the quick connection and disconnection of hydraulic hoses without the need to use additional tools and without the need to bleed the system, close valves, purge entrapped gas and pressure, or recharge the fluid. This makes quick connect couplings particularly useful in time-dependent, critical applications where speed is a factor.

All quick-connect couplings consist of two parts, a male half and a female half, that allow the proper flow and control of fluid when connected properly. There are different ways these two halves can be coupled with different connection types, such as poppet style, push-to-connect, or thread-to-connect. Another distinguishing factor is the type of valve, whether poppet, ball, or flat face.

Types Of Hydraulic Quick Connect Couplings

There are different types of quick connect couplings, such as poppet quick couplers, that utilize a basic shut-off system that blocks fluid flow from exiting the fittings or, when connected, lift the poppets of their seat to allow fluid flow through the connection. In many applications, flat face or thread-to-connect quick couplers will provide many operational improvements over the use of poppet couplers.

Flat Face Hydraulic Quick Couplersflat face hydraulic quick couplers

Flat-face hydraulic quick couplers employ a much more sophisticated interface that push face sections into each other when connected and open a large flow path. Flat-face quick couplings are designed to eliminate fluid spillage during quick connect and disconnect processes. This prevents environmental contamination, which can be costly to clean up, and provides a safer work environment for operators. The reliable, flat-face connection makes them easier to clean and less susceptible to contamination.

ISO 16028 refers to the international quality standard related to the requirements for flat face quick couplings, specifically regarding dimensions and performance levels in fluid circuits of nominal pressures between 200 and 315 bar. The ISO 16028 standard was developed based on Stucchi’s flat face quick coupling design.  Watch this quick video of the APM flat face coupling to see how the male and female halves come together to form a sealed connection allowing fluid flow with no leaks upon quick connect or disconnect. The APM is designed specifically to connect easily by hand under pressure and to relieve pressure within itself.

Thread to Connect Hydraulic Quick Couplersthreaded flat face hydraulic quick couplers

Threaded, flat-face quick couplers provide reliable connection in applications subjected to higher pressure, pressure impulses, or residual pressure and eliminate premature wear or brinelling. Thread-to-connect flat-face couplings provide reliable and leak-free quick connect and disconnect in heavy-duty, high-pressure applications, even with pressure on both sides. Stucchi offers threaded quick couplings like the VEP Series which provides solutions in heavy-duty applications like demolition and running high-flow forestry and mulching equipment. Learn more about how to use Stucchi’s VEP series and the many benefits of this threaded coupling in demanding applications.

Hydraulic Quick Coupler Materials

There are various materials that are precisely engineered for specific fluid applications.

  • Carbon steel – an alloy made with carbon and iron with a higher carbon content than stainless steel. Steel with an increased carbon content becomes stronger and has a lower melting point for more malleability and improved heat distribution. Carbon steel couplings are often the material of choice for many manufacturing applications due to their strength and durability.
  • Stainless steel – and iron alloy that is resistant to corrosion and rusting that contains at least 11% chromium but may contain other elements such as carbon, metals, and nonmetals to obtain specific properties. Chromium provides corrosion resistance in stainless steel that protects materials in the presence of oxygen. Stainless steel couplers are often used in harsh environments and applications subjected to corrosive fluids. There are different grades of stainless steel, such as 316, 360, and 630, with varying properties.
  • Brass Quick Couplers – brass quick couplings are robust and resist high temperatures, suitable for many applications with refrigerants, mold and die, and industrial applications.
  • Quench Polish Quench (QPQ) – a specialized nitrocarburizing case hardening surface treatment that enhances corrosion resistance.

Hydraulic Quick Coupler Sizes and Port Types hydraulic quick coupler sizes and port types

Stucchi offers hydraulic quick couplers in various product body sizes with multiple port options.  You can filter through specific parameters, whether looking for 1/2 in quick couplers, 3/8-in, 1/4-in, 1/8-in, or other sizes.

The coupling port refers to how our Stucchi product will interface to a hose end, tube, or other adapter, to be integrated into part of the circuit. The ports are made to certain standards to ensure a leak-free connection between the Stucchi coupling product and the fitting manufacturer. Our hydraulic specialists can help you to choose the port type required for your application with the most common options, including:

  • NPT – National Pipe Thread
  • SAE/MORB/STOR (Male O-ring Boss, Straight Thread O-ring)
  • BSP – British Standard Parallel
  • JIC – 37-degree flare
  • ORFS – O-ring Face Seal

Multi-Coupling PlatesMulti-coupling plates

Multi-coupling plates allow for the quick connection of multiple hydraulic quick couplers simultaneously, with one single, simple motion. Stucchi offers a variety of multi-coupling quick-connect solutions with multi-plates to provide the quick connection of hydraulic, pneumatic, and/or electrical lines of the same or different diameters.

Stucchi offers these many types of hydraulic quick couplers, multi-coupling connection solutions, hydraulic adapters, auxiliary hydraulic kits, and conversion kits compatible with many brand names.

Stucchi has been providing hydraulic solutions for more than 60 years and offers a variety of hydraulic quick couplers and coupling solutions to meet the most demanding applications. You can find Stucchi hydraulic quick couplers in the most heavy-duty applications, including agriculture, oil and gas, the steel industry, mobile equipment, and many others. Contact us with any questions and for assistance in troubleshooting or improving your hydraulic process with high-quality hydraulic quick couplers.