Properly assembling your fitting connections help to ensure that your systems install and stay leak-free. This is why we have started a series of assembly posts/videos featuring the proper assembly of most popular tube and port ends. Today we are talking about proper assembly steps of adjustable style parallel thread port ends, which include SAE straight threads (SAE J1926 / ISO 11926), ISO 6149, JIS B2351, BSPP flat face (ISO 1179), and DIN metric flat face (ISO 9974). Unlike tapered threads, parallel thread ports do not initiate sealing by the threads. The seal is obtained by other means, typically an elastomeric seal. When assembled properly, parallel thread ports provide the best leak-free port connection. Therefore, proper fitting assembly and installation is key to ensuring leak-free parallel thread port connections in your system.
Watch the video to learn the proper process for assembly and installation of adjustable style parallel thread port ends, or follow the steps outlined below.
Step 1: Inspect the threads.
Start by inspecting the threads and sealing surfaces. They must be free of burrs, nicks, scratches, and any foreign material to ensure that you get a proper seal connection. Also, if your fitting has a male port end that requires an o-ring, seal, washer, or retaining ring with o-ring, make sure that there is one properly installed before moving to the next step.
Step 2: Lubricate the o-ring (if it applies).
You need to lubricate the o-ring using a light coating of system fluid or a compatible lubricant. This will allow the o-ring to smoothly transition into the port or gland area.
Step 3: Back off the lock nut and washer.
Back off the lock nut as far as possible, also make sure the back up washer is not loose and is pushed up as far as possible. Note: Parker's patented Robust Port Stud eliminates the need to back off the locknut because it is delivered already backed off.
Step 4: Finger tight.
Screw the fitting into the port until the back-up washer or retaining ring makes contact with the flat surface of the port. Light wrenching may be necessary, but avoid over tightening because this may damage the washer. Note: Parker's patented Robust Port Stud eliminates this potential damage. It has a longer locknut that eliminates the upper thread from making contact with the washer, and also provides a greater grip area for the wrench.
Step 5: Align the fitting for the connecting tube or hose.
To align the tube end of the fitting for the incoming tube or hose assembly, unscrew the fitting by the necessary amount, but not more than 360 degrees.
Step 6: Tighten to proper torque.
Using two wrenches, hold the fitting in the desired position with one, and with the other, tighten the locknut to the proper torque utilizing the values shown in the Assembly and Installation section of the Parker Catalog 4300.
Step 7: Inspect.
Be sure to inspect the assembly to assure that the o-ring is not visible and that the washer or retaining ring is fully seated on the flat surface of the port.
By following these steps your parallel thread adjustable style port end connections should be leak-free. To help you ensure that all of your hydraulic fitting connections are installed properly, Parker Tube Fittings Division has created a series of tube and port end assembly and installation videos for the most common hydraulic fitting connections which will be shared on TFDtechConnect.com over the next couple of months. You can also find detailed assembly and installation information for port end threads and tube fittings in the Assembly/Installation section of our Catalog 4300.
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Contributed by Burleigh Bailey, senior product engineer at Parker Tube Fittings Division
Additional related content about hydraulic tube, hose, and port fitting connections:
Non-Adjustable Parallel Thread Port End Assembly Instructions for Hydraulic Fittings
Assembly Instructions for Ensuring Leak-Free O-ring Face Seal Fittings
Tapered Thread Port Assembly Instructions for Hydraulic Fittings
Turn vs. Torque? How Making the Right Choice Keeps Your Hydraulic Fitting Connections Leak-Free
How Many Times Can I Reassemble a Hydraulic Fitting?