JIS Hydraulic Fittings

Stainless JIS Fittings Manufacturer – 316Ti/316L/304 Hydraulic Adapters Supplier Since 1999

QC Hydraulics is a China-based manufacturer with over 25 years of experience in producing stainless steel JIS fittings. We offer corrosion-resistant, high-pressure solutions for hydraulic, marine, and industrial systems, with bulk supply and OEM/ODM services for global distributors and OEMs..

Explore Our Full Range of JIS 60° Cone Fittings & Adapters

JIS (Japanese Industrial Standard) hydraulic fittings are widely used in Japan and Asia to connect hydraulic hoses and tubes in industrial, construction, and agricultural machinery. They feature BSP threads with a 30° flare and 60° cone, ensuring a secure, leak-resistant seal under pressure. Available in various sizes, they support both low- and high-pressure applications.

QC Hydraulics produces stainless steel JIS fittings known for their precision, corrosion resistance, and durability—ideal for demanding, long-lasting hydraulic systems.

✔ Rated up to 6,000 PSI

✔ Wide size range: 1/8″ to 2″

✔ Leak-free, vibration-resistant design

✔ Made of 316Ti / 316L / 304 stainless steel

✔ Precision-machined to JIS B 2351 & JIS B 8363

✔ Thread types: JIS, BSP, JIC, NPT, ORB, ORFS, BSPP, metric

✔ Fitting types: adapter, eblow, tee, cross, plug, cap, bulkhead

JIS Hydraulic Fittings Size Chart（Refer to JIS B 0202）

Thread Size (G) Pitch (mm) TPI (Threads/Inch) Major Diameter (mm) Minor Diameter (approx, mm) Common Hex Size (mm)
G 1/8 0.907 28 9.728 ~8.5 14
G 1/4 1.337 19 13.157 ~11.5 19
G 3/8 1.337 19 16.662 ~15.0 22
G 1/2 1.814 14 20.955 ~18.6 27
G 5/8 1.814 14 22.911 ~20.5 30
G 3/4 1.814 14 26.441 ~24.0 32
G 1 2.309 11 33.249 ~30.5 41
G 1-1/4 2.309 11 41.910 ~39.0 50
G 1-1/2 2.309 11 47.803 ~44.5 55
G 2 2.309 11 59.614 ~56.0 70

Notes:
JIS hydraulic fittings commonly use BSPP (G) threads with a 60° cone seat for sealing.

These are parallel threads, and sealing is typically achieved via a metal-to-metal cone or an O-ring, not by thread interference.

Thread dimensions and tolerances follow JIS B 0202, which aligns with ISO 228-1.

JIS BSP Hydraulic Fittings – Typical Pressure Ratings (at 20°C)

Thread Size (G) Tube OD (mm) Pressure Rating – Carbon Steel (MPa) Pressure Rating – Stainless Steel (MPa)
G 1/8 6 31.5 25
G 1/4 8 31.5 25
G 3/8 10 25 20
G 1/2 12 25 20
G 5/8 14 21 17.5
G 3/4 16 21 17.5
G 1 22 16 13
G 1-1/4 28 13 10
G 1-1/2 35 10 8.0
G 2 42 6.3 5.0

Notes:
These ratings assume fittings are used in hydraulic systems with JIS 60° cone seat sealing.

Ratings are maximum working pressure at room temperature (20°C).

Pressure ratings decrease with higher temperature.

Always refer to the manufacturer’s datasheet for certified values—this chart is for general reference.

Technical Support

QC Hydraulics has the capability to engineer, design and manufacture from a concept to the real products.

Please feel free to contact us if you have any inquiries

QC Hydraulics, Your Premier Stainless Steel Hydraulic Fittings And Adapters manufacturer

QC Hydraulics is a leading manufacturer of stainless steel hydraulic hose fittings, hydraulic adapters, tube fittings and PTFE hose assembly for over 20 years. Our outstanding team, state of the art technology, strict quality control, strong production capacity as well as professional service, enable us enjoying a great reputation in domestic and overseas.

Our products are widely recognized by those global hydraulic & industrial wholesalers/distributors and OEMs in the fields of hydraulic, pneumatic, oil & gas, chemical, marine and shipbuilding etc. Besides, we are also doing OEM service for several of worldwide big brand manufacturers of hydraulic fittings, which greatly reduce their production costs, and help them win more market share.

Now QC Hydraulics become more and more popular in high quality market overseas. We always meet even exceed customer’s expectations. QC Hydraulics is a reliable and trusted supplier of wholesalers, distributors and brand manufacturers of hose and fittings.

  • State of The Art Facilities

  • Over 20 years’ Manufacturing Experience

  • Highly strict Quality Control & Inspection

  • Annual production capacity Over 4.5 million of fittings

Why Choose Us

State of The Art Facilities

We utilize state-of-the-art facilities and equipment to produce industry leading, quality stainless steel hydraulic fittings. Each facility supervisor has over 10 years of experience in the industry. Manufacturing, sales & technical support, warehouse, shipping, and quality control-have specific objectives that contribute to our overall goal of 100% customer’s satisfaction.

Zero Quality Issues

When you buy QC Hydraulics’ products, you are buying precision and reliability.In the hydraulic industry, where extreme pressures prevail, precision and accuracy are paramount. Our Quality Control Department follows strict Quality Assurance Program procedures that make certain our products meet your quality requirements. Besides, 3.1 material certificate available for each shipment to ensure you receive 100% right materials from us.

100% On-Time Delivery

With QC Hydraulics, you’ll have one less thing to worry about. We have maintained a 99.99% on-time delivery rate for 3 years in a row. That kind of consistency doesn’t just happen, we make it happen. Besides, we have the commonly used raw materials and accessories in stock that enable us make a very quick delivery time for the urgent orders.

Professional Service

As a professional manufacturer, our engineering department can provide technical service. Like new products designing, CAD drawings and technical advice. Our overseas sales department are 100% well trained with strong industry & product knowledge and service awareness, who can make a quick response within 24 hours to greatly improve the communication efficiency.

Frequently Asked Questions

We manufacture a wide range of stainless steel hydraulic adapters, including:

JIC, ORFS, NPT, NPTF, BSP, BSPT, SAE, and Metric thread types

Straight, 45° & 90° elbows, tees, crosses, reducers, and plugs

Interchangeable with Parker and Eaton standard adapters

Our adapters are designed to meet SAE, ISO, DIN, and JIS standards.

Yes, we provide standard bulk packaging as well as custom packaging options based on customer requirements. Our standard packaging includes:

Plastic caps and plugs to protect threads and sealing surfaces

Individual polybags for small-sized adapters

Heavy-duty cartons with reinforced packing for safe transportation

For distributors and wholesalers, we can also provide private labeling and custom branding.

We manufacture adapters using high-quality stainless steel:

AISI 304 (1.4301)

AISI 316L (1.4404)

AISI 316Ti (1.4571)

These materials provide superior corrosion resistance, making them ideal for high-pressure and harsh environments

Yes, we do both hydrostatic pressure and nitrogen gas pressure test. Testing reports are avaliable.

Yes, we offer custom manufacturing services for hydraulic adapters based on customer drawings, specifications, or samples. Our engineering team can assist with design modifications, thread compatibility, and performance optimization to meet specific application requirements.

Our standard MOQ is 200 pieces per item, but for larger sizes (above 1 inch), we can accept 100 or even 50 pieces. We are flexible with initial orders to help customers test our quality

Yes, we provide EN 10204 3.1 material certificates for all shipments. Our stainless steel raw materials meet ASTM A276 and ASTM A182 standards, ensuring compliance with industry regulations.

Stainless Steel Only: Unlike many suppliers who offer both carbon steel and stainless steel, we focus exclusively on stainless steel, ensuring better precision and quality.

Advanced Manufacturing: We use high-precision CNC machining and strict quality control measures.

Guaranteed Quality: 100% pressure-tested, dimensionally accurate, and ISO 9001 certified.

On-Time Delivery: Reliable lead times and stock management ensure prompt shipments.

Interchangeability: Compatible with leading global brands like Parker and Eaton.

Send us a message if you have any questions or request a quote.

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