Metal Swivel Fittings Product Spotlight

Pivoting connections for moving machine elements and air tool ease-of-use

Fittings for air, gas and liquids flow control systemsSwivel fittings bring important advantages to pneumatic and liquid flow control systems. For air tools, they significantly increase maneuverability and ease of use. For moving machine elements, they help prevent mechanical stresses on supply line hoses and lines that can cause premature aging and failure.

Swivel fittings are rotating adapters and connectors that are often made available in metal for better durability and strength. Important benefits of using swivels include

  • Extending hose life
  • Eliminating kinks in supply lines
  • Reducing maintenance frequency and costs
  • Preventing excessive hose bending and stress
  • Increasing air tool maneuverability and ease of use

In general, swivel adapters add versatility to the threaded hose and adapter connections.

Watch this short video featuring seven different swivel fittings series from the ISM catalog >> 

 

How do swivel fittings improve maintenance costs?For both moving machine elements and pneumatic rotating connections, swivel fittings improve the performance of liquid and gas supply hoses subjected to the effects of movement.

  • By providing twist-free connections for easier installation and maintenance
  • By reducing mechanical stress on hoses that can lead to premature hose failure


Installation is importantProper installation is important. Swivel fittings need to be installed so that they allow for machine movement with the least stress on the fluid or gas supply lines. Once in place, swivels should allow hoses to pivot easily and thus reduce or eliminate the stresses caused by bending, twisting, stretching and kinking.


Swivel fitting seals and sealingThe sealing surfaces of swivel fittings are very important.

All swivels have sealing surfaces of some sort and these are critical for their performance. The seals need to be tight enough to prevent pressurized air or fluid from leaking while still allowing movement. The most basic, economical swivel fittings have sealing surfaces that are essentially two carefully machined, hardened surfaces that are held together. Simple designs like these frequently also use elastomer or rubber seals to help prevent leaking.

While good seals prevent leaking, they need to allow movement and rotation so that they cause as little drag as possible. This drag or resistance to rotation is called torque drag. Torque drag is the measure of how much a swivel joint resists turning. Keep in mind that just the weight of the hoses, tubing and fittings may be enough to create a significant torque drag or load on swivels.


Swivel fittings are not rotary fittingsSwivel fittings are not the same sort of fitting as rotary unions. Rotary unions are also called rotary fittings, swivel joints, swivel unions, rotating joints, rotary joints or rotary couplings.

Rotary unions transfer pressurized heat transfer and fluid power liquids, sometimes through multiple independent fluid passages, from a stationary inlet to a rotating outlet. They are especially useful in high-speed applications used in power generation and manufacturing processes.

Rotary unions are more highly engineered than basic swivel fittings. They have bearings and specialized seals that may be pressure balanced. These and other added design features allow them to cope with the torque drag created by higher fluid pressures and higher axial loading as well as other design requirements.

Learn more about rotary unions at Dynamic Sealing Technologies >>


Swivel fittings designsMost swivel fittings are considered specialty fittings. The two basic types of swivel fittings are inline (straight-through) and elbow (right-angle). Two other fairly common styles are called ball or ball-socket and orbital. Orbital types are sometimes called offset swivels. Generally, the space available and how supply houses are routed determine which swivel fitting design will work best.

Common swivel fitting designs

  • Ball or ball-socket style swivels
  • Elbow, right-angle or 90º style swivels
  • Inline, straight or straight through style swivels
  • Orbital, offset, 360º or parallel plane style swivels

 

A S C H series metal ball swivel by hose barb connector.
ASCH swivel fitting 

ASCH Series Ball Swivel Connectors >>The ASCH series ball swivel fittings provide connections between air supply hoses and air tools as well as gas and fluid supply hoses for moving machine elements. These fittings eliminate hose kinking and twisting, which extends hose life and reduces maintenance and replacement costs. They also provide a more natural range of motion, which increases tool maneuverability and reduces operator fatigue.

The side-to-side range of motion is from 20° to 25° (40° to 50° conical range of motion) depending upon the fitting size. The ball socket can also rotate a full 360 degrees around the threaded base. Their design provides full flow at any angle. They have brass threaded bases with nickel-plated precision machined hardened steel housings to prevent galling. Read just a little further to find out more about galling*

The connections are male NPT thread by hose barb. The ball swivels load against the hardened steel cups of the base without the use of O-rings. Apply thread sealant to the NPT male threads to help prevent leaks.

  • Made in the USA
  • Brass male NPT threaded bases
  • Maximum working pressure: 225 psi
  • Nickel-plated hardened steel housings
  • Nickel-plated hardened steel ball swivel hose barbs

ASCH series male NPT thread by hose barb sizes

  • 1/4" male NPT threaded base with 5/16” or 3/8" hose barb size (hose ID) connections
  • 3/8" male NPT threaded bases with 1/4”, 5/16" or 3/8" hose barb size (hose ID) connections
     

*What is galling?Galling is a type of wear called adhesive wear. When there are two metal surfaces that slide against each other under enough of a load, the pressure and friction can cause metal to tear or shear away from one surface and weld itself (cold welding) to the other surface. The result is grooves or scoring that can lead to seizing. Brass and bronze are resistant to galling. Steel that is fully hardened is very resistant to galling.

Learn more about the factors affecting wear and galling at the British Stainless Steel Association website >>

 

M B C X series male N P T thread by hose barb brass swivel adapter.
MBCX swivel fitting 

MBCX Series Male NPT Swivel Adapters >>These basic straight inline swivel style fittings allow the hose barb to rotate a complete 360 degrees in the threaded base. This freedom of motion protects air, gas and fluid supply hoses from kinking and twisting, which increases hose life while reducing maintenance workloads and costs. The swivel action of this hose barb by male NPT thread adapter also makes installation faster and easier. Made with press fit crimp construction without the use of O-rings.

Brass provides strength, durability and good corrosion resistance, but it is susceptible to corrosion by solutions containing ammonia or amines. Apply thread sealant to the male NPT threads to help prevent leaks.

  • Brass*
  • Maximum operating pressure: 150 psi
  • Maximum operating temperature: 160ºF
  • 3/16", 1/4", 3/8", 1/2", 3/4" and 1" hose barb sizes (hose ID)
  • 1/8", 1/4", 3/8", 1/2", 3/4" and 1" male NPT threaded connections

 

Extruded, Forged or Cold-Drawn Brasses >>*Brass is a great material choice for metal fittings because of its workability, durability, toughness and corrosion resistance. Get some insight into how brass is formed, worked and shaped. This article includes the basics of some of the most important industrial brass forming techniques.

 

F B C X series female N P T thread by hose barb brass swivel adapter.
FBCX swivel fitting 

FBCX Series Female NPT Swivel Adapters >>These basic straight inline swivel style fittings allow the hose barb to rotate a complete 360 degrees in the threaded base. This freedom of motion protects air, gas and fluid supply hoses from kinking and twisting, which increases hose life while reducing maintenance workloads and costs. The swivel action of this hose barb by female NPT thread adapter also makes installation faster and easier.

Made using press fit crimp construction without the use of O-rings. Apply thread sealant to the male NPT threads to help prevent leaks.

  • Brass*
  • Maximum operating pressure: 150 psi
  • Maximum operating temperature: 160º F
  • 1/4", 3/8" and 1/2" hose barb sizes (hose ID)
  • 1/4", 3/8" and 1/2" female NPT threaded connections
     

Find out more about the corrosion resistance and chemical compatibility of brass >>
*Check out our information about chemical compatibility and get a copy of our Chemical Compatibility Chart, which includes brass, bronze and copper as well as other metals, plastics and elastomers.

 

N S X series 10 32 U N F thread male by female metal swivel adapter.
NSX swivel fitting 

NSX Series 10-32 UNF Thread Swivel Connectors >>This is another series of straight inline swivel connectors for hoses or pipe carrying fluids or gases. These fittings provide 10-32 UNF (Unified National Fine) threaded connections that can rotate a full 360 degrees.

  • Made in the USA
  • Electroless nickel-plated (ENP) brass
  • Maximum operating pressure: 125 psi
  • Maximum operating temperature 180º F
  • *Buna-N, EPDM and Fluoroelastomer (Viton®) seal options
  • Male by male or male by female 10-32 UNF threaded connections


Elastomers Chemical Compatibility Chart >>
*Wondering which elastomer seal material is the best choice for your application? Learn more about the chemical compatibility of elastomers (rubbers) and get a copy of our Elastomers Chemical Compatibility Chart.

 

A S X series N P T thread brass swivel fitting.
ASX swivel fitting 

ASX Series NPT Swivel Fittings >>A series of straight inline NPT pipe threaded swivel connectors for hoses or pipe carrying fluids or gases. A compact inline design that fits into tight areas and can rotate a full 360 degrees.

For applications that require operating pressures up to 1000 psi. A bronze thrust bearing (see below for a description) provides low torque swivel action. Brass body and ends. Apply thread sealant to male NPT threads to help prevent leaks.

  • Made in the USA
  • Male by female thread connections
  • Maximum operating pressure: 1000 psi
  • Maximum operating temperature: 180 °F
  • Bronze thrust bearing for low torque drag
  • Buna-N, EPDM or Fluoroelastomer (Viton®) seals
  • 1/4", 3/8" and 1/2" NPT pipe threaded connections


What is a thrust bearing?Thrust bearings are a particular type of rotary bearing. Rotary bearings allow rotation between connected parts. Their design transmits the physical stresses placed on the connection while also allowing the connected parts to spin freely.

Bearings generally are subject to two types of loading: radial load and axial or thrust load. Radial loads act at right angles to the bearing's axis of rotation but axial loads act in parallel to the axis of rotation.

Thrust bearings are designed to support axial (thrust) loading. Different kinds of thrust bearing designs handle different amounts of axial loading. The simplest thrust bearing design looks a lot like a flat, coin-sized washer.

Learn more about axial or thrust loads at Machine Design Magazine online >>

 

O S F series N P T thread nickel-plated brass orbital swivel connectors. Counter-clockwise from the top: male by male, male by female and female by female.
OSF swivel fitting 

OSF Series Orbital Swivel Connectors >>These compact 1/4” NPT thread compact orbital or offset swivel fittings allow a complete 360° of rotation between each segment. This design eliminates kinks in supply lines. Nickel plated brass provides additional durability and corrosion resistance. Apply thread sealant to male NPT threads to help prevent leaks.

  • Made in the USA
  • Nickel Plated Brass
  • Maximum operating pressure: 150 psi
  • Working temperature range: 20° F to 140° F

OSF series swivels are available in three different 1/4" NPT pipe threaded connection options

  • Male by male
  • Male by female
  • Female by female

 

C L S series N P T thread and 10 32 U N F thread metal swivel elbow fittings.
CLS swivel fittings 

CLS Series Swivel Elbow Fittings >>These metal swivel fittings provide compact right angle rotating connections for air, gases and fluid supply lines and hoses. Apply thread sealant to male NPT threads to help prevent leaks.

  • Made in the USA
  • UNF and NPT threaded connections
  • Maximum operating temperature: 180°F
  • Maximum operating pressure varies by connection size

CLS series 10-32 female UNF thread by 10-32 male UNF thread connections

  • Electroless nickel plated (ENP) brass
  • Maximum operating pressure: 125 psi

CLS series 1/8" female NPT by 1/8" Male NPT pipe thread connections

  • Electroless nickel plated (ENP) brass
  • Maximum operating pressure: 250 psi

CLS series 1/4" female NPT by 1/4" male NPT pipe thread connections

  • Brass
  • Maximum operating pressure: 250 psi

CLS series 3/8" female NPT by 3/8" female NPT and 3/8" female NPT by 3/8" male NPT pipe thread connections

  • Brass
  • Maximum operating pressure: 1500 psi
  • Bronze thrust bearing for low torque drag


Chemical Compatibility Chart >>Wondering if brass is the right material for your application? Check out our information about chemical compatibility and get a copy of our Chemical Compatibility Chart, which includes brass, bronze and copper as well as other metals, plastics and elastomers.


Key takeawaysIf your application involves air, gas or fluid supply lines that must accommodate movement, then swivel fittings, connectors and adapters may be the way to go. For piping they are often a necessity. For gas or liquid delivery via hoses, swivel fittings increase maneuverability and improve ease of use.

Swivel fittings also relieve or at least significantly reduce the bending, twisting, stretching and kinking that shortens hose life. As an added bonus, swivel connectors and adaptors provide faster and easier twist-free installation and maintenance.

 

Rendered model of a 5 6 4 3 0 acetal plastic small inline filter.
56430
small plastic inline filter

Get more tips and insights about air, gas and fluid flow control fittingsManufacturers make them in a wide range of sizes and types. Tremendous varieties of applications use them to control the flow of air, gases and liquids. The how and why of different component designs and materials is not always well understood though.

At ISM we strive to provide you with technical information possible. All with the intention of helping guide you in choosing the right components for evaluation and testing.

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