Fittings are used to connect hoses, pipes and tubes to hydraulic systems. They maintain a quality seal and hose pressure, also reducing the risk of torquing. But, when looking at the different types of fittings for hoses, it’s easy to get confused. There are many shapes, materials, threading and sealing types.
In this blog post, we’ll discuss the different types of fittings for hoses to help you choose the right one for your application. To start, there are two main categories – permanent crimp fittings and field attachment fittings.
Permanent Crimp Fittings
This is the most common category. Permanent crimp fittings require the presence of a crimping machine to attach the hose. A well-crimped seal is essential to a hydraulic hose because it allows the fluid to move through freely without leaks.
If you have access to the crimper, the field attachable fitting is an excellent choice they are classified into plugs, unions, elbows and crosses, depending on the shape. If properly assembled, they can meet all applicable SAE specifications. However, keep in mind that SAE is based on construction technique and the material of the hydraulic hose.
Three Types of Fittings
While hydraulic fittings for hoses fall within these two categories, they are either metal seal, soft seal or tapered thread connectors. No matter which one you use; they must hold a tight seal.
Metal Seal – uses a tapered thread combined with a machined face. They require welding or soldering to the tube.
Soft Seal – use an elastomeric seal to prevent leakage. They can withstand heavy vibration and don’t break down nearly as often as a metal seal. An example of this is ORFS fittings.
Tapered Thread – seal through deformation of the male and female thread. This type of fitting has the potential to leak.
Installation of an NPT thread is something to keep in mind. Make sure it’s intended to be permanent. If the hose needs replaced or removed on a regular basis, you’ll need a quick coupler (the JIC type), which can handle disassembly and reassembly without leakage.
When a hydraulic system has a leak, the consequences can be devasting. Therefore, it’s important to understand the different types of fitting for hoses before doing an installation.
To learn more, download our blueprint on the four things to consider when choosing hydraulic hose fittings.