Beyond Fluid, Double Ferrule Tube Fittings Supplier in China

For over 15 years, we have been a trusted supplier of twin ferrule instrumentation tube fittings, distributors, and large contractors worldwide. At Beyond Fluid, we are dedicated to solving your supply challenges and helping you expand your market share. Partner with us to achieve lasting business success.

Leading Supplier of Twin Ferrule Tube Fittings in China

Instrumentation double ferrule tube fittings consist of four key components: the fitting body, nut, front ferrule, and back ferrule.

These are double ferrule tube fittings designed to create leak-proof, torque-free seals at tubing connections, making them ideal for high-pressure and high-temperature applications such as process instrumentation and control systems.

Beyond Fluid’s compression tube fittings typically made from stainless steel material. Available in various sizes and designs, they meet specific application needs across industries, including hydrogen energy, semiconductors, fluid power, petrochemical, chemical, aerospace, defense, marine, and automotive sectors.

Specfication:

Compatible: Swagelok, Parker
Size: 1/8″-2″(Fractional)/6mm-50mm(Metric)
Material: SS304, SS316, Alloy etc
Ferrule: Twin ferrule(Special hardness treated back ferrule to provide secure)
Nut: Silver coated female nut threads to reduce galling
Connection: NPT, JIC/AN, ISO/BSP, SAE/MS, ORFS, ORB, Weld, Tube Stub, Port Connectors
Working Pressure: up to 12,100 PSI
Working Temperature: -425.2°F to 1598.0°F (-254°C to 870°C)
Tracebility: Every fitting is marked with size, material and heat number

Hot-Selling Types Of Twin Ferrule Compression Tube Fittings

Compression tube nut

Connection: compression tube nut | Size: 1/8" to 2"/6mm to 38mm | Material: SS304, SS316

compression tube ferrule

Connection: twin ferrule | Size: 1/8" to 2"/6mm to 38mm | Material: SS304, SS316

JIC Male Tube adapter

Connection: tube stub to JIC | Size: 1/8" to 2"/6mm to 38mm | Material: SS304, SS316

MALE NPT TUBE ADAPTER

Connection: tube stub to male NPT | Size: 1/8" to 2"/6mm to 38mm | Material: SS304, SS316

MALE NPT instrument TUBE FITTING

Connection: male NPT to tube | Size: 1/8" to 2"/6mm to 38mm | Material: SS304, SS316

Male BSPT instrument TUBE FITTING

Connection: male BSPT to tube | Size: 1/8" to 2"/6mm to 38mm | Material: SS304, SS316

male jic/an instrument tube fitting

Connection: male JIC to tube | Size: 1/8" to 2"/6mm to 38mm | Material: SS304, SS316

butt weld instrument tube fitting

Connection: butt weld to tube | Size: 1/8" to 2"/6mm to 38mm | Material: SS304, SS316

Instrument TUBE PORT CONNECTOR

Connection: tube stub to port | Size: 1/8" to 2"/6mm to 38mm | Material: SS304, SS316

Instrumentation Tube fitting plug

Connection: plug to tube | Size: 1/8" to 2"/6mm to 38mm | Material: SS304, SS316

adjustable instrument tube 90° Elbow

Connection: tube to adjustable | Size: 1/8" to 2"/6mm to 38mm | Material: SS304, SS316

bulkhead instrument tube fitting

Connection: bulkhead tube to tube | Size: 1/8" to 2"/6mm to 38mm | Material: SS304, SS316

Instrumentation Tube Fitting Union

Connection: tube to tube | Size: 1/8" to 2"/6mm to 38mm | Material: SS304, SS316

instrument tube fitting 90° Elbow

Connection: tube to tube | Size: 1/8" to 2"/6mm to 38mm | Material: SS304, SS316

instrument tube fitting three way tee

Connection: tube to tube to tube | Size: 1/8" to 2"/6mm to 38mm | Material: SS304, SS316

Instrument twin ferrule tube fitting cross

Connection: tube to tube to tube to tube | Size: 1/8" to 2"/6mm to 38mm | Material: SS304, SS316

Competitor Cross Reference For Typical Twin Ferrule Fittings

Beyond Fluid’s SS twin ferrule instrumentation tube fittings are equivalent to Swagelok, Parker, SSP and Superlok. Please see below examples for reference.

Beyond Fluid	Swagelok	SSP DUOLOK	Parker A-LOK	Superlok
-TN Series	SS-402-1(Example 1/4”)	ISSD-N Series	4NU4-SS(Example 1/4”)	SN Series
-MC- Series	SS-400-1-4(Example 1/4“)	ISSD Series	4MSC4N-SS(Example 1/4″)	SMC-N Series
-TU Series	SS-6 Series	SSD-U Series	4SC4-SS(Example 1/4″)	SU Series
-UE Series	SS-9 Series	ISSD-L Series	1E-SS Series	SUE Series
-AME Series	SS-ST Series	ISSD-MEST Series	8M5SEL8-SS(Example 1/2″)	SPME-U Series
-MAD-MN Series	SS-4-TA-1-4(Example 1/4″)	ISSD-AM Series	4AM4N-SS(Example 1/4″)	SMA-N Series
-CF Series	SS-400-7-4 Series(Example 1/4″)	ISSD4CF4(Example 1/4″)	4FSC4N-SS(Example 1/4″)	SFC-N Series
-TC Series	SS-C Series	ISSD-C Series	4BLEN4-SS(Example 1/4″)	SC Series
-FAD-MN Series	SS-4-TA-7-4(Example 1/4″)	ISSD4AF4(Example 1/4″0)	4AF4N-SS（Example 1/4″)	SFA-N Series

Features of Double Ferrule Tube Fittings

Beyond Fluid’s tube fittings are engineered to meet demanding industrial standards. These twin (double) ferrule fittings, also known as instrumentation fittings, deliver superior leak-tight performance and are fully comparable to top U.S. brands like Swagelok and Parker A-Lok.

Each fitting consists of four parts: body, nut, front ferrule, and back ferrule. The dual-ferrule design ensures excellent tube grip and vibration resistance. During assembly, the back ferrule drives the front ferrule forward to seal against the fitting body while securely swaging the tube.

Application of Double Ferrule Tube Fittings

Twin or double ferrule fittings are easy to install, requiring no welding or threaded connections, which reduces labor costs. They are reusable, cost-effective, and offer long-term reliability.

These fittings are widely used in industries such as:

Shipbuilding • Chemical processing
Oil and gas • Power generation
Pharmaceuticals • Semiconductors
Vacuum applications • Hydrogen Applications

Pressure Ratings For Fractional Seamless Stainless Steel Tubing

Tube OD (in)	WT(in) 0.028″	WT(in) 0.035	WT(in) 0.049	WT(in) 0.065	WT(in) 0.083	WT(in) 0.095	WT(in) 0.109	WT(in) 0.120
1/8	8500	10900
3/16	5400	7000	10200
1/4	4000	5100	7500	10200
5/16	4000	5800	8000
3/8	3300	4800	6500	8600
1/2	2600	3700	5100	6700
5/8	2900	4000	5200	6000
3/4	2400	3300	4200	4900	5800	6400
1		2400	3100	3600	4200	4700	5300	6200
1 1/4		2400	2800	3300	3600	4100	4900
1 1/2			2300	2700	3000	3400	4000	4900
2			2000	2200	2500	2900	3600

Pressure Ratings For Metric Seamless Stainless Steel Tubing

Tube OD (mm)	WT(mm) 1.0	WT(mm) 1.5	WT(mm) 2.0	WT(mm) 2.5	WT(mm) 3.0	WT(mm) 3.5	WT(mm) 4.0	WT(mm) 4.5
6	420	670
8	310	490
10	240	380
12	200	310	430
14	180	280	390
15	170	260	360
16		240	330
18	210	290	370
20	190	260	330
22	170	230	300
25		200	260	320
28		180	230	280	330
30		170	210	260	310
32		160	200	240	290	330
38		170	200	240	280	310
42				180	210	250	280
50				150	180	200	230	260

Tube Fittings Temperature Ratings:

Reductions in nominal pressure (PN) can occur due to the temperature of the fluid medium or the surrounding environment. Refer to the table below for details:

38°C	93°C	149°C	204°C	260°C	316°C	343°C	371°C
1	1	0.97	0.9	0.85	0.84	0.82	0.81

399°C	427°C	454°C	482°C	510°C	538°C	566°C	593°C
0.81	0.80	0.79	0.78	0.77	0.77	0.73	0.62

621°C	649°C	677°C
0.49	0.37	0.28

Elastomer's Temperature Rating

When selecting seal materials, the seal’s temperature rating may become the limiting factor for the fitting’s overall temperature rating. Please refer to the temperature rating table below for guidance:

Material	Temperature Range
NBR	-25°C to 110°C (Default Option)
Viton	-28°C to 204°C
PTFE	-30°C to 315°C

Installation Torque For Tube Fittings

The nuts of Beyond Fluid tube fittings are all silver plated and glaze our own patented. In this way, the installation torque can be controlled within a reasonable range. Especially in the case of narrow space or suspended operation, it makes installation very easy. The table is the installation torque data:

Item	Fractional Size	Metric Size	Torque value before glaze	Torque value after glaze
1	1/4”	6mm	16	11
2	5/16”	8mm	26	15
3	3/8”	/	45	24
4	/	10mm	52	29
5	1/2”	12mm	76	43
6	5/8”	14, 15, 16mm	101	54
7	3/4”	18, 19mm	132	68
8	7/8”	20, 22mm	161	83
9	1”	25mm	195	98
10	1.1/8”	28mm	215	107
11	1.1/4”	30, 32mm	248	126
12	1.1/2”	38mm	310	160
13	/	42mm	380	196
14	2”	50mm	490	252

Installation Instruction For Tube Fittings

Tube Fitting Installation Guide

Tube Fittings Up to 1 in./25 mm

Insert the tube fully and finger-tighten the nut.
Mark the nut at the 6 o’clock position.
Tighten:
- Small sizes (≤4 mm or ≤3/16″): Turn to 3 o’clock (¾ turn).
- Larger sizes (≥6 mm or ≥¼”): Turn to 9 o’clock (1¼ turns).

Tube Fittings Over 1 in. / 25 mm

Preswage ferrules onto the tube using the MHSU tool.
Lightly lubricate body threads and back ferrule rear surface.
Insert the tube until the front ferrule seats; finger-tighten the nut.
Mark the nut at the 6 o’clock position.
Hold the body steady; tighten the nut ½ turn to the 12 o’clock position.

Reassembly Instruction For Tube Fittings

Reassembly Instructions

Beyond Fluid tube fittings can be reassembled over 15 times. Always depressurize the system before disassembly.

Before disassembly, mark the nut and fitting body to record the pulled-up position.
Insert the tube with preswaged ferrules until the front ferrule seats.
Hold the fitting body steady and tighten the nut with a wrench to the marked position.
When resistance increases, tighten the nut slightly—about 1/8 turn.

Manufacturing Process For Double Ferrule Tube Fittings At Beyond Fluid

At Beyond Fluid, we take great care in manufacturing our twin ferrule instrument fitting. From the first mold to the final packaging, every step is closely monitored to ensure strict quality control. This meticulous process guarantees that our products meet the highest standards of excellence.

Design and Engineering
Material Procurement
CNC machining
Heat Treatment (Selective)
Cleaning and Surface Treatment
Assembly
Testing
Marking and Tracebility
Packaging

Technical Support

At Beyond Fluid, we pride ourselves on our comprehensive expertise in engineering and designing double ferrule compression fittings. From the initial concept to the final product, our team is equipped to transform your ideas into tangible, high-quality fluid and control solutions. Our commitment to innovation ensures that we deliver not just products, but value-driven solutions tailored to your needs.

Tailored Solutions
Techical Support
Free Drawings Service

Who We Are

Beyond Fluid, Your Reliable Compression Tube Fittings Manufacturer

Beyond Fluid has over 15 years of experience supplying stainless steel twin ferrule fittings and valves to wholesalers, distributors, and large contractors. We offer reliable quality, excellent service, on-time delivery, and competitive prices. Our commitment to advanced technology, precision engineering, and strict quality standards ensures we meet the diverse needs of customers worldwide.

We take pride in producing high-quality instrumentation fittings and valves. Our comprehensive range of products is designed for optimal performance and durability, with both standard and customized solutions. Serving industries from oil and gas to shipbuilding, we aim to be your long-term trusted partner to expand your market presence.

15+

Years of Experience

Why Choose Us

Reliability. Consistency. Integrity

Quality Assurance

When you choose Beyond Fluid, you ensure precision and reliability, backed by our strict Quality Assurance Program.

on-time delivery

Beyond Fluid ensures reliability with a 99.99% on-time delivery rate and quick response to urgent orders through stocked materials.

Competitive pricing

Our robust manufacturing and supply chain enable us to offer competitive prices, helping clients expand their market reach.

professional service

Our expert engineers offer design, CAD, and technical support, while our trained sales team ensures fast, efficient 24-hour responses.

Testimonials

What Our Clients Say

A Large Wholesaler From USA

“We’re literally satisfied with Beyond Fluid’ always on-time delivery and exceptional handling of requests. Their commitment to timely service is evident and consistently reliable. Their swift response and guaranteed on-time delivery make them my preferred choice.”

A Brand Manufacturer From Germany

“We can always count on Beyond Fluid’s quality. During a 2018 visit, their advanced facilities and stringent quality controls made a lasting impression on us. Their timely responses to requests for drawings or technical support further solidify my trust. We really love to place our orders to those suppliers like Beyond Fluid.”

FAQ

Frequently Asked Questions.

Here are a few real most popluar questions from our clients.

Are your instrumentation fittings compatible with other brands or systems?

Yes, Beyond Fluid's twin ferrule tube fittings are fully compatible with other big brands, like Swagelok and can be easily integrated into existing systems, offering customers flexibility and ease of use.

How can I trust the quality and reliability of instrumentation fittings?

Our instrumentation fittings and valves follow strict quality control protocols and meet industry-leading standards, ensuring consistent performance and dependable reliability.

Can you customize instrumentation fittings according to our specifications?

Yes, we provide customization options to tailor valves, fittings, and tubing to meet the unique requirements of each customer's application, ensuring optimal performance and efficiency.

Are you able to manufacture instrumentation fittings with our brand(OEM service)?

Sure, we provide OEM services for several leading global brands in instrument fittings and valves, significantly reducing their production costs and helping them gain greater market share.

Can you provide samples before placing a firm order?

Sure, we can provide samples of instrument fittings for evaluation firstly.

Do you provide after-sales support?

Yes, we do offer after-sales support, including technical assistance, troubleshooting, and warranty services. Besides, We offer a customer-friendly policy: we’ll either send a free replacement or issue a credit right away. We're committed to making things right for you.

What is the price range of your Instrument tube fittings?

Thanks to our excellent supply chain management, and more than 15 years of experience in production, most of our wholesalers and distributors are happy with our prices.

What is your common payment terms?

Our typical payment term is 30% T/T in advance, balance payment against BL copy. But for serious buyers/companies, we’re open to discussing more flexible payment terms, such as a 30% deposit with the balance due within 30 days after shipment. We can work out the details later.