When it comes to hydraulic fittings, compatibility is a vital factor. The type of hose or fluid that you use must be compatible with the hydraulic fitting. Otherwise, you risk explosion, fire, and toxic fumes. This is why it’s important to use proper fittings and check them frequently.
Pipe Thread
Pipe threads are a fundamental feature of hydraulic fittings. They connect two pieces of pipe together to prevent leaks and maintain the pressure within the cylinder. The types of threads available are NPT, BSPP, and tapered. Threads in hydraulic tube fittings are usually either parallel or tapered. In addition to these types, fittings with different thread sizes are available.
A tapered thread is a type of thread that seals by deforming both the male and female threads. This results in the male and female becoming tighter when the female is inserted into the male. The force forces the male thread peak to push against the female thread crest. As a result, the thread crushes itself and forms a seal. This can be fixed by applying a tapering compound or pipe dope.
Sometimes, the same thread may be used in several hydraulic fittings. In these cases, the fittings are labeled with the type of thread. NPT, for example, is compatible with male iron pipes, while BSP is compatible with female iron pipes. Whether the fitting is female or male, the thread type will depend on its intended purpose.
While pipe thread identification can be challenging, it is essential for safety. Selecting the correct thread when replacing a hydraulic fitting is very important. If you don’t, you can damage the thread during installation. This could compromise the seal’s reliability and reduce its pressure-holding capacity.
O-Ring Seals
O-ring seals in hydraulic fittings are used to ensure the integrity of hydraulic components. They are a versatile solution for sealing components in a variety of conditions. Compared to all-metal face types, O-rings require lower torque ranges. However, they must be properly tightened to avoid stripping threads or deforming components. Under-tightening can also lead to weak seals.
Before using a hydraulic fitting, it is crucial to check its dynamic pressure rating and lubrication. This rating is based on normal operating conditions with moderate mechanical and hydraulic shock. A de-rating factor should be used if the operating conditions are more severe. This factor is provided in the table below. Also, before installing the fitting, it is necessary to check it for contamination or damage during the shipping and storage process. In addition, it should be lubricated with a light lubricant.
Hydraulic fittings that use an O-ring as the seal must be carefully inspected and maintained. If the O-ring is damaged, it may be time to replace it. Replacement O-rings are available in 90 durometer neoprene. These O-rings can be found individually or as a kit with many of the most common sizes.
Identifying Hydraulic Fittings
When working with hydraulic hoses, you must know how to identify different types of hydraulic fittings. The first thing to look for is a seal. A fitting’s seal is determined by the type of thread used. The different types of threads include UN/UNF, NPT/NPTF, BSPP, metric parallel thread, and tapered thread. These threads can help you identify the type of hydraulic hose fitting you need.
Once you’ve figured out which type of hydraulic hose fitting you need, you can begin ordering the right one for your needs. Fortunately, the process is easy if you know what kind of connector you need. In most cases, you can order it from a supplier, but if you’re not sure what type you need, you’ll need to use some old-fashioned methods such as measuring and observation.