ORB Port Types and Their Applications


ORB fittings stand apart from other threading standards by placing more focus on O-ring sealing to provide efficient and long-term performance. This makes these fittings efficient and durable.

Recommended by the National Fire Protection Association for optimal leakage control in medium and high-pressure hydraulic systems, these connections use straight UNF threads with O-ring seals for maximum reliability in applications where alignment isn’t a necessity.

SAE J514

Hydraulic systems demand precision. That is why selecting fittings that best meet professional or domestic use can be crucial. Acknowledging various port types and their applications is also vital in optimizing performance while upholding system integrity.

ORB fittings are among the most widely-used hydraulic fitting types, offering durable design and reliable operation across a variety of uses. Their durable straight thread and O-ring boss seal ensure high pressures don’t leak out, while adapters provide complete connections.

ORB fittings come in various sizes to meet every application need. From small ORBs designed for tight spaces and lightweight applications such as automotive systems or smaller machinery to medium ORBs that offer the optimal blend of power and space for more extensive industrial/commercial equipment and finally, large ORBs explicitly created to handle heavy-duty tasks and massive machines, we have something to meet any application.

SAE J514 is the standard that describes the dimensions and properties of ORB hydraulic fittings while also including a coded size system to help industry and government agencies quickly identify and order suitable ORBs for their applications. Each fitting in this coded size system features a dash number representing its diameter in sixteenths of an inch – for instance, a fitting with dash number 12 070101 SA is classified as a 4/16″ ORB fitting.

These straight-thread connections are frequently found in hydraulic and fluid power systems. Both male and female components come equipped with 37o seats that create an effective seal when the male flared seat contacts a coned seat on a female component; threads also serve as mechanical connections.

O-ring hydraulic fittings are known for being highly reliable. Their O-ring seal fits tightly over the male thread to form an airtight seal when tightening down on a nut, providing leakproof performance that also stops hose movement or expansion under pressure.

O-rings enable ORBs to withstand harsh environments and mechanical stress, making them an excellent choice for hydraulics applications. Their inherent strength also allows them to cope well under extreme vibrations and temperature changes.

Thread Pitch

Thread pitch for orb fittings refers to the number of threads per inch and plays an essential role in how quickly and easily their fittings can be tightened or loosened. A higher thread pitch provides more flexibility, while lower ones make installation or removal more challenging. If you are unsure of your orb fitting’s thread pitch, a simple way to determine this value is with a thread gauge; measure its port diameter using calipers before using your gauge to count how many threads per inch exist within its thread pattern – knowing this information helps find orb fittings suitable for your application quickly!

O-rings are unsung heroes of hydraulic fittings; their role is to prevent leakage from the seal, especially under high-pressure scenarios where leakage could result in system failure. Not only can O-rings avoid leakage, but their adaptability allows them to accommodate minor imperfections between mating parts while still creating an airtight connection.

ORB fittings are a reliable solution for medium and high-pressure hydraulic applications, while our ORB O-Ring Boss Thread Adapters provide an attractive alternative to FFOR styles; their vibration tolerance rating surpasses industry norms by 15 times!

Avoid expensive mistakes by choosing the appropriate ORB fitting for your application. A great way to do this is by measuring the port hole diameter with a caliper and then comparing this number against our chart below. If you need assistance selecting an ORB thread size, reach out and explore our wide selection of hydraulic adapters!

ORB threads may resemble other fitting types but should never be interchanged without prior research and approval from experts. JIC threads feature a 37deg flare with an integral seat to connect male and female threads – these threads are capable of withstanding high working pressures but may crack under over-tightening; also, Light DIN metric fittings have different thread pitches which do not align with ORB connectors.


Selecting an ORB fitting size and material with care can mean the difference between seamless system operation and leaks. There are numerous factors to keep in mind, such as thread count and material used. Common ORB materials include carbon, nickel-plated carbon, stainless steel, and Viton O-rings from FKM Buna-n or Viton, with these connected to FKM (Buna-n) O-rings to seal against operating pressures; thus, it must match up perfectly to your system operating pressures for smooth system operation.

ORB thread types differ from NPT and AN in that they’re designed to withstand higher operating pressure without creating leak points, making them suitable for hydraulic applications.

ORB fittings come in various forms, such as elbows, tees, and adapters to meet any system design. They can also be combined with standard fittings such as JIC, NPT, or BSPP; however, adapters may be necessary as each of them has distinct threading and sealing mechanisms.

Small ORB Fittings are perfect for tight spaces and lightweight applications such as automotive systems or small machinery, while medium ORB fittings are the Goldilocks of the ORB world, suitable for an array of industrial and commercial equipment. Large ORB Fittings can handle massive hydraulic systems that demand substantial pressure and volume;

At the core of selecting an ORB fitting is making sure it matches your system requirements regarding pressure, flow, and temperature. Selecting appropriate material and O-ring options can prevent leaks while increasing system reliability.

O-rings are compressed in the female ORB port when male threads mate to create a leakproof seal and should always be seated appropriately or mismatched, as this could cause leakage or further damage during installation or service life. Therefore, having spare O-rings on hand is always wise in case any are lost or damaged during assembly, so be prepared for every possible situation and have extras handy in case something goes amiss!


O-rings come in various shapes and sizes. Standard inch and metric O-ring sizes can be identified by their inside diameters and cross-section (thickness) dimensions, respectively. When selecting an O-ring, other vital factors to keep in mind include compression ratio, indentation depth, indentation pressure, elastic memory, and flexible memory retention – each creating different results in terms of mechanical stress that leads to premature damage or failure, whereas reduced indentation will help it seal more effectively and ensure it seals more reliably.

An O-ring is constructed using an elastomer material that can be selected based on its intended application. Different materials have different temperature-, chemical- and environmental tolerance levels; silicone O-rings can withstand hydraulic oil, gasoline, and hydrocarbons like propane while still functioning with air, oxygen, and chemicals like acids and oxidizers; polyurethane O-rings have more excellent tear, abrasion, and age resistance allowing use in hydraulic, cylinder valve fittings as well as pneumatic tools.

Some applications require O-rings that can withstand high temperatures. This type of O-ring can be found in petroleum refining, turbine engines, gas and steam generation, and aerospace applications; medical, food & beverage, and chemical processing facilities often utilize these types of O-rings with increased temperature requirements – this O-ring must withstand cleaning processes such as sterilization as well as any aggressive methods such as cleaning or sterilization processes.

Cyclic and dynamic operating conditions also pose challenges to O-rings since their seal must adapt to changing surface pressures, resulting in excess stretching or compression of an O-ring, leading to its failure as a seal. Furthermore, dynamic applications may involve compression by protrusions from shafts through O-ring grooves, leading to shaft protrusion into O-ring grooves, causing this compression force to squeeze O-ring extrusions between seal surfaces that could result in extrusions into clearance gaps between seal surfaces.

As such, it is vitally important that one understands how an O-ring will be installed; its correct seating must be ensured to avoid damage during installation. A tool may help in this respect – measuring diameter and depth. Likewise, calculations must also be undertaken regarding compression ratio to make sure that at least 15% less compression occurs in its groove than its maximum compression value.