Swagelok® Medium-Pressure Tube Fittings (FK Series)
The two-piece design of Swagelok® FK series medium-pressure tube fittings reduces installation time and lowers maintenance costs. These fittings provide a vibration-resistant, leak-tight, and robust connection that protects workers and the environment.
FK series fittings have revolutionized fluid connections in downhole oil and gas exploration applications and streamlined R&D fluid systems requiring frequent reconfiguration. These fittings also aided in the development of the hydrogen economy through leak-tight hydrogen fluid connections that meet the requirements of EC-79 for performance at pressures up to 700 bar [10 150 psig] in hydrogen applications.
The design of Swagelok FK series fittings consists of a female fitting body and a preassembled cartridge containing the male nut and color-coded front and back ferrules on a disposable arbor. The preassembled cartridge ensures current ferrule orientation, visual confirmation of ferrule presence, and proper installation into the female body. These fittings are available in 316 stainless steel, alloy 2507, and alloy 625. The body/cartridge combination allows for easy installation using either specified turns or torque using standard tools.
Learn How to Assemble FK Series Medium-Pressure Tube Fittings
Medium-Pressure Tube Fittings Catalogs
The strain-hardened 316 stainless steel FK fitting bodies are available in straight, elbow, and tee shapes to meet your configuration needs in a lightweight, space-saving design. Find detailed product information, including materials of construction, pressure and temperature ratings, options, accessories, and installation instructions in the product literature provided here.
FK and IPT Series Products Cone and thread or medium-pressure tube fitting connections Excellent corrosion resistance in chloride-containing environmentsManufactured to meet NORSOK and NACE® MR0175/ISO15156
Features: 316 stainless steel construction; Temperatures up 1000°F (537°C); Medium-pressure (MP) fittings, Size range—1/4 to to 1 in., Pressure rating—up to 20 000 psig (1378 bar); High-pressure (HP) fittings, Size range—1/4 to 9/16 in., Pressure rating—up to 60 000 psig (4134 bar); NACE® MR0175/ISO15156 compliance available
Tube Fittings Comparison (FK Series)
Watch and compare installation of FK series and cone and thread fittings.Compare the Fittings
Swagelok Resources Curated for You
Read how Swagelok helped an offshore oil operator reduce installation labor time and enhance overall performance by changing existing cone and thread connections with Swagelok's FK series fittings.
The Swiss Federal Laboratories for Materials Science and Technology (Empa) and Swagelok are exploring the viability of hydrogen-based transportation solutions. One recent research breakthrough stemming from our collaboration incorporated Swagelok’s FK series fittings within the Empa hydrogen solution. Using FK series fittings instead of traditional Swagelok tube fittings significantly eased installation, while improving leak-tightness, reliability, and safety.
FK Series Medium-Pressure Tube Fittings
From initial construction and commissioning through daily operations and maintenance, there is a tremendous focus on reducing total lifecycle costs. FK series tube fittings can reduce maintenance costs and provide high reliability, reducing system downtime, when proper assembly processes are followed. These fittings can also help mitigate environmental impact via leak reduction as well as improve overall safety by protecting your system against corrosion.