Metric Hydraulic Fittings Manufacturer in China

DIN 2353 / ISO 8434-1 / ISO 6149
Carbon Steel / Stainless Steel
Support Drawing, Sample, Custom Production
Multi-SKU, OEM and Recurring Purchasing Support

Product List

Topa supplies metric hydraulic fittings for hose assemblies, tube systems, hydraulic ports, equipment connections, and transitions between metric and inch-based standards.

Product selection should be based on the connection standard, thread diameter and pitch, sealing method, tube outside diameter, hose size, fitting configuration, material, pressure requirement, and mating component. Review the specifications of each product before adding it to a multi-SKU quotation.

Products Video

This video presents selected metric hydraulic hose fittings, tube fittings, adapters, elbows, tees, bulkhead fittings, plugs, and transition connections. It shows different body configurations, thread arrangements, sealing surfaces, materials, surface finishes, and product identification details.

Metric connections shown in the video may use different sealing methods, including 24° cones, O-ring port seals, flat-face seals, and other specified interfaces. Visual similarity alone does not confirm interchangeability.

For quotation and specification review, provide the connection standard, thread diameter and pitch, sealing type, tube OD, hose size, configuration, material, surface finish, quantity per SKU, and total SKU count.

Application

Metric hydraulic fittings are used in equipment and systems that employ metric tube connections, hose ends, or hydraulic ports. The required fitting depends on the equipment design, regional standard, tube or hose specification, operating pressure, fluid, temperature, corrosion exposure, and installation space.

Confirm the Correct Metric Connection Before Ordering

Send your product list, existing part numbers, drawings, or specification table for connection and dimensional review. Include the required quantity per SKU and purchasing schedule to support an accurate quotation.

Metric Fittings Types

Metric fittings can have either parallel or tapered threads, each offering specific advantages. Parallel threads typically require an O-ring seal or another sealing method, ensuring a leak-tight connection when compressed. The O-ring is reinforced with a back-up washer and a nut, maintaining correct orientation and creating a reliable seal when the male and female parts connect.

DIN 2353 / ISO 8434-1 24° Cone Connections

DIN 2353 / ISO 8434-1 covers metric 24° cone tube-fitting systems using cutting rings or compatible O-ring sealing cones. These connections are available in defined series and tube sizes.

DIN 7631

DIN 7631 fittings are designed with a 60-degree cone in hydraulic applications. This design allows for effective sealing and pressure retention, suitable for a wide range of hydraulic systems.

DIN 74234 and DIN 74233

These fittings use a 45-degree cone, providing a balance between sealing efficiency and installation ease. Their design is common in specific hydraulic applications requiring this angle for proper sealing.

Komatsu Fittings (JIS B2070)

The Komatsu hydraulic fittings, following the JIS B2070 specification, feature a 60-degree flare, typically used for hose adapters. These fittings are prevalent in Japanese-made machinery, offering excellent reliability in high-vibration environments.

French G GAZ Fittings

Common in French hydraulic systems, Kobelco French G GAZ fittings use a 24° sealing surface and metric straight threads. These fittings are similar to German DIN fittings but feature fine threads across all sizes, unlike the coarser threads used in larger German DIN fittings.

ISO 6149-1

ISO 6149-1 is one of the most recognizable metric thread forms for North American users, primarily employed for ports on pumps, valves, and actuators. These fittings are similar to SAE ORB ports but use a bonded rubber washer to create a seal inside a machined turndown at the face of the port.

Thread Standards

Metric hydraulic fittings include several distinct connection systems. A complete specification should identify both the thread and the sealing interface.

OEM & Custom Capability for Metric Hydraulic Fittings

Standard products solve common demand, but many OEM and replacement projects require more exact matching. Our custom support helps youo handle structure changes, brand presentation, and sample confirmation in one workflow.

Custom Thread

Support metric, BSP, NPT, and JIC thread requirements for different market and system standards.

Custom Structure

Support angle, length, and special fitting structure changes to match actual installation space and connection layout.

Logo Marking

Support laser marking or stamping to help buyers build brand consistency and improve product identification.

Special Packaging

Support bag, box, and label customization for retail packing, warehouse management, and brand presentation.

Drawing-Based Production

Support quotation and production by technical drawing to reduce matching mistakes and speed up engineering review.

Request a Sample!

For qualified OEM, distributor, and recurring purchasing projects, product specifications can be reviewed before volume production. Where pre-production approval is required, confirm the part numbers, drawings, quantity per SKU, annual or recurring demand, material, finish, marking, packaging, and inspection requirements.

How to Identify Metric Threads: A Step-by-Step Guide

Identifying metric threads is crucial for ensuring compatibility in hydraulic and mechanical systems. Here’s a practical guide to help you accurately identify metric threads, ensuring a secure and reliable connection.

Step 1: Examine the Thread Form

The first step is to determine the type of thread form. Metric threads typically have a straight, parallel design, unlike other thread types like BSP or NPT, which are either tapered or angled. Look closely at the angle of the thread. Most metric threads, especially those per ISO standards, have a 60-degree thread angle (such as DIN 7631), while some like DIN 2353 and ISO 8434 feature a 24-degree cone.

Step 2: Measure the Thread Pitch

Metric threads are specified by their pitch, which is the distance between adjacent thread crests. To measure the pitch:

Use a thread pitch gauge (also called a thread gauge tool), which has various blades designed to match thread pitches.

Place the gauge on the threads and find the one that fits perfectly, matching the distance between threads.

The pitch is commonly measured in millimeters (mm) for metric threads, with values ranging from 0.5mm to 4.0mm (or more) for common hydraulic fittings.

Step 3: Measure the Outer Diameter

Next, measure the outer diameter of the male thread using calipers. This will give you the nominal size of the fitting (e.g., M10, M16, M22). The “M” stands for metric and the number refers to the outer diameter in millimeters.

For example, an M10 fitting means the outer diameter of the male thread is 10mm.

Step 4: Check the Thread Type (Parallel or Tapered)

Metric threads can either be parallel (where the threads run straight) or tapered (where the threads gradually narrow). To identify the type:

Parallel threads are common in fittings like DIN 2353, where the diameter remains constant along the length of the thread.

Tapered threads (such as ISO 7 and ISO 6149-1) gradually become smaller as they move away from the base.

Step 5: Identify the Seal Type (if applicable)

Metric threads often feature sealing elements like O-rings, bonded rubber washers, or cone seals. Check if the fitting includes any seal type, which is especially important in high-pressure systems. These seals ensure that the fitting remains leak-free, contributing to system safety and efficiency.

Step 6: Confirm Thread Pitch and Size Using Standards

Once you’ve measured the pitch and outer diameter, refer to international metric thread standards, such as ISO 261 and DIN 13, to confirm the specifications. These standards provide a reference chart for different thread sizes and pitches, allowing you to cross-check your measurements and identify the correct fitting.

Identifying metric threads requires attention to detail, but by following the steps above, you can be confident that you are matching and selecting the correct fitting for your system.

Avoid Common Pitfalls

At Topa, we take great care to ensure that all our metric hydraulic fittings are sized accurately, made from high-quality materials, and undergo rigorous testing for compatibility and performance. Our custom packaging solutions guarantee that your fittings arrive in perfect condition, while our comprehensive catalog allows you to easily select the correct fitting type and material for your application. With flexible ordering options and an experienced team ready to assist with any queries, Topa helps you avoid the common pitfalls in procurement, ensuring a smooth and efficient purchasing experience.

Incorrect Sizing

One of the most common mistakes in purchasing metric hydraulic fittings is selecting the wrong size. Metric fittings come in various sizes, and getting the wrong dimensions can lead to poor sealing, leaks, or even system failure. Always verify the required outer diameter (OD) and thread size before ordering. For best results, cross-check the specifications with your hydraulic system’s requirements.

Unsuitable Material Selection

Choosing the wrong material can compromise the fitting's durability and resistance to corrosion, especially in harsh environments. Metric hydraulic fittings are available in materials like stainless steel, brass, and carbon steel, each with its own benefits and limitations. Make sure to select a material that aligns with your system’s pressure ratings, environmental conditions, and chemical exposure.

Inadequate Surface Treatment

Surface treatment is essential for enhancing corrosion resistance, improving wear resistance, and ensuring long-term durability. Be cautious of suppliers offering uncoated fittings that may not withstand corrosive environments. Always check the surface finish—whether it’s chrome-plated, zinc-coated, or other protective coatings—to ensure that it meets the requirements of your application.

Choosing the Wrong Fitting Type

Metric hydraulic fittings come in different types, such as compression fittings, flare fittings, and straight fittings. Selecting the wrong type of fitting for your system can lead to installation difficulties or system inefficiencies. Make sure you understand the specific needs of your application (e.g., sealing type, thread form, pressure rating) before making your purchase.

Inconsistent or Poor Packaging

Improper or inadequate packaging can lead to damaged fittings during shipping or storage. Ensure that the fittings are well-protected in sealed bags or boxes to prevent scratches, dents, or contamination. Check for any signs of damage before accepting deliveries, as damaged goods can compromise the integrity of the fittings.

Ordering the Wrong Quantity

Overordering or underordering is a common procurement pitfall. Overordering can tie up capital and increase storage costs, while underordering can delay production and repairs. Accurately forecast the quantity you need based on your system's requirements, expected usage, and potential future maintenance needs.

Our Team

Topa Services

Customized Solutions

We provide tailored hydraulic fittings to meet your specific size, material, and design requirements, ensuring perfect compatibility with your systems.

Multi-SKU Quotation

Product lists can be reviewed by connection type, part number, size, configuration, material, finish, and quantity per SKU.

Specification Review

Drawings, reference numbers, catalogs, samples, and measurements are checked against the required connection and sealing details.

Customer Support

Our dedicated customer service team is available to assist with technical queries, product recommendations, and after-sales support, ensuring a smooth experience from start to finish.

Choose Topa

Manufacturing Process

From raw material to final inspection, every hose fitting goes through controlled machining steps to help you get stable quality and reliable batch consistency.

Quality Check

Each hydraulic fitting is checked through a series of inspection and testing procedures to ensure consistent performance, reliable sealing, and long service life in hydraulic systems.

Hardness Testing

Material hardness is tested to ensure the fitting has the required strength and durability. Proper hardness helps prevent deformation, cracking, or failure under high-pressure working conditions.

Surface Roughness Testing

Surface roughness is inspected to ensure proper sealing performance. A controlled surface finish helps reduce leakage risks and improves connection reliability.

Profile Inspection

Profile testing is used to verify the shape and angle of threads and sealing surfaces. This ensures that each fitting matches standard specifications such as JIC, BSP, or ORFS connections.

Salt Spray Testing

Salt spray testing evaluates corrosion resistance of the plated surface. This helps ensure the fittings can perform reliably in humid, outdoor, or harsh operating environments.

Supply & Delivery Capability

Reliable supply is a key part of purchase decisions.

Stock for Common Sizes

Different metric fitting types and sizes can be organized into one consolidated purchasing plan.

● Mixed fitting types and configurations
●Quantity planning by individual SKU
●Consolidated quotation and shipment

Monthly Capacity

Stable production capacity is important for buyers managing large projects and long-term supply plans.

● Monthly capacity: 100000 pcs
● Support for bulk and scheduled orders
● Stable production planning

Peak Season Support

Delivery stability during busy seasons matters for distributors and OEM buyers.

● Stable delivery during peak season
● Better scheduling for repeat orders
● Lower risk of delayed shipment

Export Experience

Export experience reduces communication risk and helps buyers handle documents, packing, and shipment arrangements more smoothly.

● Export experience: 50+ countries
● Familiar with international shipment process
● Support for long-term overseas supply

Main Markets

Existing market coverage helps buyers judge whether products and service already fit their regional standards and demand habits.

● Main markets: USA
● Main markets: Europe
● Main markets: Asia

Delivery Coordination

Supply is not only about production. Delivery coordination also affects purchase timing, stock turnover, and project progress.

● Support delivery schedule confirmation
● Better communication on order progress
● Helpful for repeat and planned purchasing

FAQ

What is metric hydraulic fitting?

The metric hydraulic fitting is a compression fitting that consists of a body, o-ring, and nut. It has a good seal and can connect metric hydraulic hoses to hydraulic fittings.

What information is required to identify a metric hydraulic fitting?

Confirm the male or female thread, thread diameter, pitch, sealing-seat type, tube outside diameter, hose size, fitting configuration, material, finish, and mating component. Photos and existing part numbers can support identification but should not replace dimensional verification.

What is the difference between L and S series metric fittings?

L and S identify light and heavy series within relevant metric 24° cone systems. They may differ in tube OD combinations, threads, body dimensions, mating components, and allowable pressure. Confirm the complete series specification before ordering.

What is Metric hydraulic fitting's material?

The metric hydraulic fitting can be selected from steel, stainless steel, and brass materials, the choice of material being related to the pipe to be connected, and the application scenario.

What to pay attention to when choosing Metric hydraulic fitting?

First, the diameter of the fitting and the hose should match. Secondly, the choice of material for Metric hydraulic fitting should consider the environment where it is located, such as pressure, humidity, temperature, etc. Finally, what kind of application, such as quick connect or welding form.

How to connect Metric hydraulic fitting?

Firstly, the hose should be cut to the right size with a cutting machine. Secondly, choose the right Metric hydraulic fitting in terms of use scenario and demand. finally, tighten the nut to achieve the purpose of pressing the ferrule.

How are hydraulic metric fittings measured?

First, you measure the inner and outer diameters of the hydraulic fitting with a caliper, next you calculate the distance between adjacent threads.

Are DIN 2353 and ISO 6149 fittings interchangeable?

No. DIN 2353 / ISO 8434-1 generally refers to 24° cone tube connections, while ISO 6149 specifies metric-threaded ports and stud ends with O-ring sealing. Similar thread measurements do not confirm that the sealing geometry and mating components are compatible.

Can you cross-reference an existing metric fitting part number?

Existing supplier numbers, drawings, catalogs, samples, and photos can be used as reference points. Final approval should verify the connection standard, thread, sealing surface, tube or hose size, key dimensions, material, finish, and application requirements.

Can different metric fitting types be combined in one order?

Metric hose fittings, tube fittings, adapters, bulkheads, plugs, and transition connections can be reviewed as a consolidated multi-SKU requirement. Provide the part number, specification, material, finish, and required quantity for each SKU.

Metric Hydraulic Fittings Manufacturer in China

DIN 2353 / ISO 8434-1 / ISO 6149

Carbon Steel / Stainless Steel

Support Drawing, Sample, Custom Production

Multi-SKU, OEM and Recurring Purchasing Support

Product List

ORB Metric Fitting

Products Video

Application

Construction

Oil & Gas

Transportation

Confirm the Correct Metric Connection Before Ordering

Send your product list, existing part numbers, drawings, or specification table for connection and dimensional review. Include the required quantity per SKU and purchasing schedule to support an accurate quotation.

Metric Fittings Types

DIN 2353 / ISO 8434-1 24° Cone Connections

DIN 7631

DIN 74234 and DIN 74233

Komatsu Fittings (JIS B2070)

French G GAZ Fittings

ISO 6149-1

Thread Standards

Thread Standards

Size Range

Material Options

Pressure Range

Surface Treatment

Matching Support

OEM & Custom Capability for Metric Hydraulic Fittings

Custom Thread

Custom Structure

Logo Marking

Special Packaging

Drawing-Based Production

Request a Sample!

How to Identify Metric Threads: A Step-by-Step Guide

Step 1: Examine the Thread Form

Step 2: Measure the Thread Pitch

Step 3: Measure the Outer Diameter

Step 4: Check the Thread Type (Parallel or Tapered)

Step 5: Identify the Seal Type (if applicable)

Step 6: Confirm Thread Pitch and Size Using Standards

Avoid Common Pitfalls

Incorrect Sizing

Unsuitable Material Selection

Inadequate Surface Treatment

Choosing the Wrong Fitting Type

Inconsistent or Poor Packaging

Ordering the Wrong Quantity

Our Team

Topa Services

Manufacturing Process

Raw Material Check

Cutting

CNC Machining

Thread Machining

Surface Treatment

Inspection and Packing

Quality Check

Hardness Testing

Surface Roughness Testing

Profile Inspection

Salt Spray Testing

Supply & Delivery Capability

Stock for Common Sizes

Monthly Capacity

Peak Season Support

Export Experience

Main Markets

Delivery Coordination

FAQ

What is metric hydraulic fitting?

What information is required to identify a metric hydraulic fitting?

What is the difference between L and S series metric fittings?

What is Metric hydraulic fitting's material?

What to pay attention to when choosing Metric hydraulic fitting?

How to connect Metric hydraulic fitting?

How are hydraulic metric fittings measured?

Are DIN 2353 and ISO 6149 fittings interchangeable?

Can you cross-reference an existing metric fitting part number?