3/8" Tube Fitting Manufacturer
- Manufactured to ASTM F1387 standards
- Double ferrule design: handles vibration, temperature, and pressure
- Silver-plated nut threads: prevents galling and seizing
- 6,000 psi pressure rating
Why Choose NPTLOK 3/8" Tube Fittings？
3/8″ Tube Fittings are made to ASTM F1387 specifications.
All NPTLOK tube fittings are made from 316 stainless steel as standard. We can supply other materials such as SS316L, SS304/304L, Brass, Monel, Super Duplex etc on a special order.
Our product range includes 3/8″ union, 3/8″ male connector, 3/8″ female connector, 3/8″ union elbow, 3/8″ male elbow, 3/8″ female elbow, 3/8″ union tee, 3/8″ male tee, 3/8″ union cross. We can offer a range of thread sizes from 1/4” up to 1” in a variety of thread types such as NPT, BSP and metric.
Our 3/8" Tube Fitting Range
Connecting two 3/8″ OD tubes ends together. This is the most common fitting for 3/8″ tube systems.
Connects a 3/8″ OD tube to a male thread. Comes in NPT, BSP and Metric threading. Thread sizes from 1/4” to 1”.
Connects a 3/8″ OD tube to female thread. Same thread options. NPT, BSP, or metric. Thread sizes from 1/4″ to 1”.
90° bend, 3/8″ OD tube connections. Used in very restricted areas.
Features of Our 3/8" Tube Fittings
Prevents galling and seizing. No stuck nuts.
The inside of the 3/8” OD fitting body is made with a hardened.
Low torque required. Fast installation. Improves delivery time.
Tested and certified. Video available on request.
Tube Requirement, Use the Right Tubing
Double ferrule fittings require bright annealing tubing. This smooth surface allows the ferrule to bite correctly.
We supply the 3/8″ OD tubing in 6 meter straight lengths normally. Furthermore, in order to enhance efficiency and save installing cost, we can also provide coiled 3/8″ OD tubing.
Easy to Tighten, Fast Installation
3/8″ tube fittings have been designed for easy use when tightening up. No high torque required. No special tools required.
Benefits for you：
- Workers install faster: less labor cost
- Faster production schedule: improve your delivery time
- Consistent installation: less rework
A short video is also available that details how to quickly and easily install 3/8″ tube fittings. If you would like to receive a copy of the video, please contact us.
6,000 psi Pressure Rating, Proven Performance
3/8″ tube fittings from NPTLOK are rated for a 6,000 psi working pressure. Also we guarantee that every batch of fittings has been pressure tested. We will send you the test report for your 3/8″ tube fittings.
Our 3/8″ fittings tested at 6,000 psi pressure. You can check our videos below. No leaks. No deformation.
We accept higher pressures and can use thicker wall tubing. Contact us to customize your 3/8″ tube fittings.
Silver-Plated Threads, No Galling, No Seizing
Every one of our 3/8″ stainless steel tube fittings have silver-plated nut threads. This effectively avoids wear, seizing, and galling during use, so you don‘t have to cut the tube.
Hardened Fitting Body, Stronger Under Pressure
The inside of the 3/8” OD fitting body is made with a hardened. This increases strength and pressure resistance.This is especially important for the 3/8″ OD double ferrule sealing and prevents leakage. These are used for higher flow and pressure applications.
3/8“ tube fittings are typically used in pressure gauges, transmitters, analyzers, control panels. 3/8” tubing provides higher flow than 1/4“ for multiple instruments on one panel. Double ferrule design seals tight under vibration from nearby pumps and compressors. No leaks. No false readings.
3/8“ tube fittings are typically used in corrosive media, high temperature, safety-critical systems. 3/8“ tube fittings handle corrosive media, high temperature, and safety-critical systems. Made from 316 stainless steel, they resist aggressive chemicals. The hardened ferrule seat keeps 3/8“ tube fittings leak-free under high pressure cycles.
3/8” tube fittings perform in high pressure, high temperature, and sour gas service. Silver-plated threads prevent galling when assembling 3/8“ tube fittings in tight spaces. Temperatures range from -200°C to +650°C.
3/8” tube fittings are used in steam lines, cooling systems, and instrument air. Double ferrule design handles thermal cycling without leaking. Graphite packing option allows 3/8” tube fittings to work up to 538°C (1,000°F) for steam service.
3/8” tube fittings control chemical addition, process lines, and recovery boilers. They carry abrasive black liquor and corrosive chemicals. A hardened body makes 3/8” tube fittings resist wear longer than standard fittings.
3/8” tube fittings are used in hydraulic systems, pneumatic controls, and general industrial lines. Easy to tighten: no high torque, no special tools. Workers install 3/8” tube fittings faster, reducing labor cost.
3/8” tube fitting fits tubing with an actual OD of 0.375 inches. 3/8“ NPT is a pipe thread with an actual OD of about 0.675 inches. They are completely different. Not interchangeable.
ASTM F1387 is the industry standard for tube fitting performance. It tests pressure holding, vibration resistance, and temperature cycling. Meeting this standard means the fitting has been rigorously tested.
No. Bright annealing tubing has a smooth surface. The ferrule needs this smooth surface to bite correctly. Regular tubing has surface oxide or roughness. The ferrule cannot bite. It will leak. Do not skip this.
Straight lengths (6 meters) are good for shop installation. Coiled tubing is better for field installation: easier to transport, no need to straighten on site, saves labor. Tell us your installation environment. We will recommend one.
No. Only a wrench. No torque wrench. No flaring tool. Just follow the 1-1/4 turn rule.
