Straight swivel fittings AB : typ TN426

Inch-metric swivel fittings. Straight connections with ED seal and swivel nut -Straight fitting body AB. B = male thread, A = swivel nut. Fittings from the category below are a variation of a standard straight fitting with ED seal, which is additionally equipped with a swivel nut. Alternative designation : Adjustable fitting EGE (Connector AB) ; EGE – Adjustable straight fitting with ED seal. We offer all types of body connectors, with male, female, swivel nut threads, etc.

What are straight fittings BA (Male/Female) ? 

Straight fittings BA Male-Female are fastening elements enabling the connection of various installation components. Their main task is to provide a tight and durable connection between hoses, valves, or other elements of the hydraulic system. They have male threads designated as B (Male) and female threads designated as A (Female), allowing for their versatile application in various hydraulic system configurations. Straight fittings BA Male-Female are used in many industries, including machinery, construction, and agriculture. They are used for connecting hydraulic hoses in construction machinery, irrigation systems, or industrial installations. Thanks to them, it is possible to create flexible and modular hydraulic systems adapted to individual needs.

Technical parameters of swivel fittings 

• connection side : BSP thread with ED seal
• hose side : swivel nut with internal metric thread
• Execution : galvanized free-cutting steel.
• catalog card of straight fitting with BA nut

Straight swivel fittings BA – construction and principle of operation

Straight swivel fittings type BA (male thread + nut) are among the most commonly used elements in power hydraulics, especially in systems based on the DIN 2353 standard. Structurally, they correspond to solutions such as the TN 426 series used by hydraulic fitting manufacturers. These are straight connectors equipped with a male connection thread with a seal and a nut with a female thread on the other side. On one side, there is a male thread (metric or BSP), which ends with a sealing surface with an O-ring. This type of solution ensures very high connection tightness, eliminating the need for additional seals such as Teflon tape. On the other side, there is a nut with a female thread, enabling quick and secure connection with another system element. Such a design solution allows for easy assembly and disassembly of the installation, while simultaneously guaranteeing resistance to high operating pressures and vibrations occurring in hydraulic systems.

O-ring seal – advantage over traditional solutions

In fittings of this type, the O-ring type seal plays a key role, working in the connection thread seat. In standard solutions, seals made of NBR (Perbunan) are used, which ensure tightness in the temperature range from approximately -35°C to +100°C, while in special versions, FPM (Viton) is used, which allows operation up to +120°C . Thanks to the use of an O-ring, we obtain:

• immediate tightness without the need for additional sealing,
• resistance to pressure pulsations,
• greater connection durability,
• repeatability of assembly (important in service and production).

Compliance with norms and industrial standards

Fittings of this type are designed in accordance with industrial standards used in power hydraulics, primarily:

• DIN 2353 / ISO 8434-1 – cutting ring system,
• DIN 3852 (form E) – threads with front O-ring seal

Thanks to this, they can be used in most European hydraulic systems and are compatible with elements from many manufacturers.

Where are BA fittings with a nut used?

Straight swivel fittings are used wherever the following is required:

• quick connection of hydraulic elements,
• possibility of repeated assembly and disassembly,
• high tightness without additional sealing materials,
• resistance to high operating pressure.

Most commonly they are used in:

• agricultural and construction machinery,
• industrial systems,
• mobile hydraulics,
• service and workshop installations.

Difference between a classic adapter and a BA fitting

Unlike standard hydraulic reductions, BA fittings with a nut offer greater assembly functionality. The nut allows for precise positioning of the element without the need to rotate the entire fitting, which is of great importance in tight assembly spaces. Additionally, the use of a male thread with an O-ring increases the tightness of the connection compared to classic tapered threads.

How to select the correct swivel fitting?

The selection of the appropriate element should take into account:

• thread type (metric, BSP),
• nominal diameter,
• operating pressure range,
• material of construction (steel, stainless steel),
• operating temperature.

In practice, it is very important to match it to a specific hydraulic system – therefore, it is worth using technical support to avoid assembly errors and leaks.

Expert support and availability at Hydron

At Hydron, straight swivel fittings are available in a wide range of dimensions and configurations, compatible with the most popular hydraulic systems. Thanks to large stock levels and the team's experience, it is possible to quickly select the right solution even for demanding applications. We provide technical support at every stage – from selection to implementation in the installation.

Order now and improve your hydraulic installation

If you are looking for proven straight swivel fittings with O-ring sealing that will ensure tightness and reliability in all operating conditions – choose the solutions available at Hydron. Choose quality, compatibility, and operational reliability in power hydraulics.