We all know about using the STAMP (Size, Temperature, Application, Media, Pressure) method when choosing the right hydraulic hose fitting for your needs. We also know the goal is to have a leak-free connection that can handle the specific application. But what are the most popular fittings and why are they so common?
You will get efficient and thoughtful service from SANYEFLEX.
The most common hydraulic fitting styles are O-ring, Mated Angle, and Tapered Thread. Each of these three come in different variations for different applications.
O-ring Fittings
There are three types of O-ring fitting designs: O-ring Boss, O-ring Face Seal and O-ring flange. As one might imagine, each has an O-ring that creates the seal.
O-ring Boss (ORB) Fittings: the O-ring seats between the threads and wrench flats and is situated around the OD of the male threaded end of the fitting. It seats against the female port to provide a very reliable leak-tight seal. O-ring boss fittings are either adjustable or non-adjustable.
Adjustable O-ring fittings are typically elbows or tees that are installed in a fixed direction and utilize a back-up washer which forces the O-ring into the cavity as the lock nut is tightened. They are considered adjustable because they are aligned toward a mating member before tightening.
Non-adjustable O-ring fittings are plugs and straight connectors that fit directly into a port without requiring alignment.
ORB fittings are highly preferred in many applications because they provide optimal sealing in medium to high pressure systems, as recommended by the National Fire Protection Association (NFPA).
O-ring face seal (ORFS) fittings have the O-ring situated in the face of the fitting to create a seal between two connected metal surfaces. When the connection is tightened, the O-ring compresses against a flat face of the mating fitting, tube or other mating female port. Though Nitrile 90 Durometer O-rings are most frequently used in ORFS fittings, there are many other compounds used depending on the application, such as a fluorocarbon or other material in very high temperature environments.
With design engineers increasing system pressures, which can result in added vibration, O-ring face seals are becoming even more popular due to their resistance to these high-vibration applications.
For more hydraulic fitting manufacturersinformation, please contact us. We will provide professional answers.
Material Selection Depends on System Temperature Ratings
Whether O-ring Boss or O-ring face seal, the operating temperatures for the fitting assemblies is dependent on the temperature ranges for the O-ring seal materials as shown in the table below.
Mated Angle Fittings
The two most popular mated angle (flare) hydraulic fittings are JIC 37-degree and SAE 45-degree. JIC 37-degree flare fittings are often used for high pressure applications in off-road and agricultural equipment, such as hydraulic loaders, excavators and tractors. Comparatively, SAE 45-degree flare fittings are more frequently seen in low to medium pressure applications, such as military and aerospace equipment. The flares and mating seats of these two fitting styles can only mate with a corresponding angle and are not interchangeable with each other.
Flare fittings have tapered ends that fit into a flared piece of tubing. They are seated in place with a threaded nut, providing a leak-tight and pressure-resistant seal. The tubing is flared with a flaring tool, such as a mandrel or rolling cone, yet pneumatic flaring tools are used for quick and accurate assembly.
Angled hydraulic flare fittings have either parallel or straight threads, yet the threads don&#;t actually form the seal. Instead, a seal is formed when the two mating flared angle seats (male and female) are joined together.
JIC fittings, also known as flare fittings, SAE 37-degree tube fittings and SAE J514 fittings are the most popular types of hydraulic fittings in America and are generally interchangeable with AN fittings. They are frequently used in hydraulic hose assemblies as the hose end adapter for the commonly used female JIC swivel fittings. In most cases, JIC fittings are rated for higher pressures in correlation with the specific tubing size-- often incorporating an elastomeric O-ring seal for a leak-proof connection. They are commonly manufactured in nickel alloys, brass, carbon & stainless steel. The most common JIC 37-degree flare fittings are made of carbon steel, with operating temperatures ranging from -65°F (-53°C) to +400°F (204°C).
SAE 45-degree fittings are machined with a 45-degree flare seating surface and are frequently used in automotive, refrigeration and air conditioning; as well as military and oil and gas industries for fuel equipment, plumbing, gasses and vacuum lines. They are not compatible with JIC connections due to the different flare angle. They are typically made of brass and designed for use with low pressure brass, copper, steel or aluminum tubing. SAE 45-degree flare fittings are easy to reassemble many times without affecting the seal, as long as they are not over-tightened. Overtightening can lead to distortion, cracking or cross threading due to brass&#; soft material. They are ideal for low and high temperature applications, able to withstand intermittent temperature ranges of -65°F (-54°C) to 250°F (121°C). However, at wide temperature ranges, the maximum allowable pressure drops significantly.
NPT, BSPT and Metric Tapered Thread Fittings
Tapered threads achieve a metal-to-metal pressure-tight seal when assembled. Unlike O-ring and mated angle hydraulic fittings, tapered threads require the use of a thread sealant (such as Teflon tape) to create a pressure-tight seal. They are used to effectively seal pipes for fluid and gas transfer.
Tapered threads make effective seals because the male and female threads compress and wedge together, providing a strong, leak-resistant connection. NPT pipe thread is the most common tapered pipe thread in the United States and Canada, though they are not compatible with British BSPT or Metric pipe threads. Metric threads are the most common style in Europe and have a precise inner and outer cylindrical diameter measured in millimeters.
The thread angle, otherwise known as an included angle, is 60 degrees for NPT and Metric threads, where BSPT threads have a 55-degree angle. Their thread shapes are also different, with NPT threads having flattened peaks and valleys, while BSPT threads are rounded.
The distinctive difference in metric threads is the V-shaped thread form, as well as male and female threads, both of which are parallel. Metric threads come in coarse and fine pitches. Coarse threads are more popular with a default pitch size, whereas fine threads have a smaller pitch size. To identify the difference, coarse threads are distinguished only by diameter, while fine threads are recognized by diameter as well as pitch size.
Sources Include:
Essentra PLC
Brennan Industries #1
Brennan Industries #2
Tapered threads achieve a metal-to-metal pressure-tight seal when assembled. Unlike O-ring and mated angle hydraulic fittings, tapered threads require the use of a thread sealant (such as Teflon tape) to create a pressure-tight seal. They are used to effectively seal pipes for fluid and gas transfer.Tapered threads make effective seals because the male and female threads compress and wedge together, providing a strong, leak-resistant connection. NPT pipe thread is the most common tapered pipe thread in the United States and Canada, though they are not compatible with British BSPT or Metric pipe threads. Metric threads are the most common style in Europe and have a precise inner and outer cylindrical diameter measured in millimeters.The thread angle, otherwise known as an included angle, is 60 degrees for NPT and Metric threads, where BSPT threads have a 55-degree angle. Their thread shapes are also different, with NPT threads having flattened peaks and valleys, while BSPT threads are rounded.The distinctive difference in metric threads is the V-shaped thread form, as well as male and female threads, both of which are parallel. Metric threads come in coarse and fine pitches. Coarse threads are more popular with a default pitch size, whereas fine threads have a smaller pitch size. To identify the difference, coarse threads are distinguished only by diameter, while fine threads are recognized by diameter as well as pitch size.
July 14,
How to Identify the Correct Hydraulic Hose Fittings
When you have a worn hydraulic hose fitting, you'll have to identify exactly which type you have so you know what to order from your supplier. If you've written all these connectors down somewhere, you'll be ahead of the game, and won't have any difficulty. If you aren't really sure what type of connector you need, you'll just have to determine it the old-fashioned way, and that involves some observation and some measuring.
Why are There so Many Different Types of Hydraulic Fittings?
While there might be hundreds if not thousands of hydraulic fittings and connectors, they all boil down to
What are the Most Common Fitting Types?
The most common types of fittings are listed below, along with a brief description of each:
- NPT/NPTF - the most commonly used type of thread in North America, these are recognizable by the tapered inner diameter and the tapered outer diameter, making the fitting self-sealing.
- BSPT (JIS-PT) - commonly known as the British Thread Type, these are standard fittings which have been internationally adopted for sealing pipe ends and making connections.
- Metric Taper - the most commonly used thread type in Europe, it is well known for its precise cylindrical inner and outer diameters.
- SAE Straight Thread - a very reliable and reusable thread type, these have excellent sealing because of the 90-durometer O-Rings.
- ISO - has a metric straight thread O-Ring port, which is very useful for diagnostic port applications.
- JIS-B - largely used as hose adapters for equipment designed in Japan or Korea, these usually have BSP threads
- DIN Metric - DIN is the German Industrial Standard, and these are popular throughout Germany and much of Europe
- BSPP (JIS-PF) - JIS stands for Japanese Industrial Standards, and these BSPP connectors follow the standard British thread dimensions
- 4-Bolt Flange - there are a number of different types of 4-bolt flange options, either for normal duty or heavy duty
What are the Most Common Hydraulic Connections?
Given the fact that
- 37 degree flare
- 30 degree flare (metric)
- 45 degree flare
- 24 degree flareless (SAE)
- 24 degree flareless (DIN)
- 30 degree flare (BSPP)
- O-Ring Face Seal (ORFS)
- 60 degree NPSM Swivel
- 60 degree Cone (BSPP)
- 60 degree Cone (Metric)
To determine the type you're actually working with, there's a simple four-step process involved. First of all, you need to figure out whether it's a permanent or reusable type, and the permanent fittings will be those which are crimped. These are easier and quicker to attach than reusable fittings are, and that makes them ideal for applications in the fluid power industry.
Next you need to identify the port connections before you attempt to install a hose or tube assembly, and those port connections are the ones listed above. Then you need to identify the particular sealing method, and this will generally be an automated angle, tapered threads, or an O-ring. After having determined the sealing method, you have to use a seat gauge in order to determine the seat angle.
The last thing you need to do is measure the thread, and this will call for the use of calipers. By determining the number of threads per inch on both the outside diameter and the inside diameter, you'll be able to get an accurate reading of the thread size. Now that you know exactly which kind you're working with, it will be fairly easy for you to call a supplier and order that precise connector.
High-Quality Fittings and Connections From Sapphire Hydraulics
If you're still not sure of which kind of fittings and connections you need for your equipment, we can help you.
When you have a worn hydraulic hose fitting, you'll have to identify exactly which type you have so you know what to order from your supplier. If you've written all these connectors down somewhere, you'll be ahead of the game, and won't have any difficulty. If you aren't really sure what type of connector you need, you'll just have to determine it the old-fashioned way, and that involves some observation and some measuring.While there might be hundreds if not thousands of hydraulic fittings and connectors, they all boil down to three basic types . These three types are either metal seal, soft seal, or tapered thread connectors. No matter which of these types of fittings yours belongs to, it will be required to satisfy two conditions: it must seal and it must hold. In some cases, the same mechanism can fulfill both functions, and in other cases, two different parts of the same mechanism will handle the necessary functions. Tapered pipe connectors are cut on a taper with a pipe's diameter, and it changes along the entire threaded portion of a pipe, in order to make the connection tighter. These types of fittings require a sealer, so you can be sure there will be no leakage around the fitting, and this is usually accomplished with a chemical sealant or a tape sealant. While it might be difficult to orient the tapered pipe threads correctly, it's very important to do so, because a poor seal might result in leakage when pressure is applied. If there is a disadvantage to tapered pipe connections, it's that they must be either soldered or welded to tubes when making a connection. Metal seal connectors were invented largely to provide an alternative to tapered pipe thread varieties. This type uses a tapered thread combined with a machined face, to provide a seal capable of handling the typical high pressure associated with hydraulics. The thread helps to accomplish the holding power, while the sealing is managed by the machined face. These kinds are easier to orient than a tapered connector, and they generally provide a better seal, without the need for any kind of additional sealant. However, they do still require welding or soldering to the tube. Soft seal are probably the most popular type used today, and these have an elastomeric seal that prevents leakage even under high-pressure situations. One of the big advantages to using soft seal connectors is that they can be installed very quickly, and this is highly advantageous in industrial applications. They are also capable of resisting heavy vibrations which many systems are subject to, so they don't break down nearly as frequently.The most common types of fittings are listed below, along with a brief description of each:Given the fact that industrial equipment and machines are designed and produced by manufacturers all over the world, it's not surprising that there are countless different types of fittings and adapters. This enormous array of fittings makes use of a number of different sealing methods and thread forms, and while many of these would appear to look the same or at least very similar, it's not that difficult to accurately identify exactly which type it really is. The most common types of fittings are shown below, and these may be used in particular countries of the world, or by manufacturers everywhere on an individual continent.To determine the type you're actually working with, there's a simple four-step process involved. First of all, you need to figure out whether it's a permanent or reusable type, and the permanent fittings will be those which are crimped. These are easier and quicker to attach than reusable fittings are, and that makes them ideal for applications in the fluid power industry. Next you need to identify the port connections before you attempt to install a hose or tube assembly, and those port connections are the ones listed above. Then you need to identify the particular sealing method, and this will generally be an automated angle, tapered threads, or an O-ring. After having determined the sealing method, you have to use a seat gauge in order to determine the seat angle. The last thing you need to do is measure the thread, and this will call for the use of calipers. By determining the number of threads per inch on both the outside diameter and the inside diameter, you'll be able to get an accurate reading of the thread size. Now that you know exactly which kind you're working with, it will be fairly easy for you to call a supplier and order that precise connector.If you're still not sure of which kind of fittings and connections you need for your equipment, we can help you. Contact us at Sapphire Hydraulics so we can provide you with the precise fitting for your needs. Keep us in mind for any customized equipment you might need to have designed and manufactured, as well as whenever you might need repairs to your hydraulic hoses or hydraulic cylinders.
If you want to learn more, please visit our website china fiber braid hydraulic hose.