Straight reducing fitting BB BSP 1" / 1.1/2" 125 bar

Straight fitting BB BSP 1" / 1.1/2" is a steel hydraulic connector designed for the direct connection of two components with different sizes of BSP connections. On one side, there is a BSP 1" male thread, on the other, a larger BSP 1.1/2" male thread. The reducing design allows a transition between two diameters in a single body.

The fitting features a 60° sealing cone and is intended for use in power hydraulic systems. The body is made of free-cutting steel, and the surface is protected by zinc plating with white passivation. The maximum working pressure specified for this model is 125 bar, and the operating temperature range is from -20°C to +120°C.

Technical parameters of the BB BSP 1" / 1.1/2" fitting

• product type: straight hydraulic fitting BB,
• type: reducing fitting,
• thread 1: male BSP 1",
• thread 2: male BSP 1.1/2",
• BSP 1" thread size: 33.0-33.2 mm outer / 30.3-30.8 mm inner,
• BSP 1.1/2" thread size: 47.4-47.8 mm outer / 44.8-45.3 mm inner,
• sealing cone angle: 60°,
• working pressure: 125 bar,
• operating temperature: from -20°C to +120°C,
• material: free-cutting steel,
• surface protection: zinc plating with white passivation,
• manufacturing standard: BS5200 / ISO 8434-6,
• medium: hydraulic oil,
• purpose: connecting elements of a hydraulic installation,
• designation according to Rastelli-Raccordi: 34.67.24.16,
• designation according to Vitillo: ARGG2416,
• alternative designation: 1B-16-24 / XGR 1 1/2"-1".

Reducer BSP 1" to BSP 1.1/2"

The different sizes of both connections mean that this is a reducing fitting BSP 1" / 1.1/2". It allows for a direct connection of an element with a BSP 1" thread to a component having a larger BSP 1.1/2" connection. Both sides of the fitting are equipped with male threads.

This solution is useful when building new installations, repairing, and modernizing machinery where individual components have different connection diameters. Instead of making a reduction using several separate adapters, a single properly selected body can be used.

Other diameter configurations can be found in the category BSP straight imperial fittings.

Large difference in diameters in a single body

The transition from BSP 1" to BSP 1.1/2" means a distinct change in connection size. The outer diameter of the smaller thread is approximately 33.0-33.2 mm, while the larger one is about 47.4-47.8 mm.

The difference is therefore easily noticeable during measurement. Nevertheless, when identifying an old component, you should not rely solely on the diameter. You should also check the thread pitch and the design of the sealing surface.

How to identify a BSP 1" thread?

The BSP 1" designation is a nominal value and does not correspond to an actual outer diameter of exactly 25.4 mm. In the presented fitting, the BSP 1" thread has an outer diameter of approximately 33.0-33.2 mm.

If you get a value of about 33 mm when measuring with a caliper, this may indicate a BSP 1" thread. For certain identification, however, the thread pitch and connection standard must be additionally confirmed.

How to identify BSP 1.1/2"?

The larger side of the fitting has a BSP 1.1/2" male thread. According to the product parameters, its outer diameter is approximately 47.4-47.8 mm.

The 1.1/2" designation is also nominal. You should not, therefore, expect a diameter of 38.1 mm resulting from a direct conversion of 1.5 inches to millimeters.

Why does BSP 1.1/2" measure almost 48 mm?

BSP threads are pipe threads whose inch designations are nominal. This is important when identifying hydraulic connectors yourself, as directly converting inches to millimeters leads to incorrect results.

For the presented product, the BSP 1" has an outer diameter of about 33 mm, whereas the BSP 1.1/2" is about 47.6 mm. These values are much more useful when measuring with a caliper than the nominal designation itself.

60° sealing cone

The fitting features a 60° sealing cone. When selecting mating components, it is therefore necessary to verify not only the diameter and type of BSP thread, but also the design of the surface responsible for connection tightness.

This is particularly important in power hydraulics. The ability to mechanically screw two components together does not guarantee that they will create a proper hydraulic connection. The sealing surfaces should be compatible with each other.

Working pressure of 125 bar

The maximum working pressure specified for the fitting is 125 bar. This value must strictly be taken into account when selecting for a specific machine or installation.

A large connection diameter does not automatically imply a high permissible pressure. Individual sizes of BSP fittings can have completely different working pressure values. Therefore, parameters should always be checked for the specific product.

If you are assembling the entire connection, also verify the permissible pressure of the crimped hydraulic hoses, fittings, valves, quick couplings, and other accessories.

Why might a larger fitting have a lower pressure rating?

Connection size and permissible working pressure are separate parameters. The BSP size primarily determines the geometry and size of the connection. It does not provide direct information about the maximum working pressure of a specific component.

Therefore, BSP fittings with smaller diameters can have a higher permissible pressure than the presented BSP 1" / 1.1/2" variant. For this product, the correct value is 125 bar.

Free-cutting steel and zinc plating with white passivation

The fitting body is made of free-cutting steel. The surface is protected with zinc plating with white passivation. This is a popular solution used in the production of steel fasteners for power hydraulics.

The material of the fitting should always be matched to the working environment, medium, and operating conditions of the machine. In the case of installations requiring increased corrosion resistance, a stainless steel design can be considered.

Such variants are available in the category stainless steel straight fittings.

Operating temperature from -20°C to +120°C

The operating temperature range specified for the fitting is from -20°C to +120°C. Hydraulic oil is indicated as the working medium in the product description.

When determining the permissible temperature of the entire system, the parameters of the hoses, seals, valves, and other components must also be checked. The maximum temperature of the complete installation is limited by the component with the lowest temperature resistance.

Standard BS5200 / ISO 8434-6

The fitting belongs to the BSP system manufactured according to BS5200 / ISO 8434-6. The manufacturing standard is essential when selecting mating components and searching for equivalents.

When replacing an old component, you must therefore compare not only the thread size but also its pitch and the design of the sealing surface.

BSP 1" and 1.1/2" versus other inch threads

Specifying the size in inches is not enough to unequivocally identify a hydraulic connector. Various inch thread systems are encountered in machinery, including BSP, BSPT, NPT, and JIC/UNF.

A similar diameter does not mean compatibility. Attempting to screw together two different standards can lead to thread damage or sealing problems.

Application of the BSP 1" / 1.1/2" fitting

The fitting can be used wherever a straightforward transition between a BSP 1" connection and a larger BSP 1.1/2" connection is necessary. The reducing design finds application both in new installations and during machinery repairs and modernization.

• power hydraulic systems,
• agricultural machinery,
• orchard machinery,
• forestry machinery,
• construction machinery,
• industrial equipment,
• hydraulic power units,
• oil installations,
• hydraulic system repairs,
• modernization of machinery and equipment.

One reducer instead of several adapters

A direct transition from BSP 1" to BSP 1.1/2" allows limiting the number of components needed to make a connection. Instead of a set of consecutive adapters, a single body with appropriately selected threads can be used.

Fewer components mean a shorter connection and fewer points requiring proper tightening. This is particularly advantageous in machines with limited assembly space.

Replacement designations for the BSP 1" / 1.1/2" fitting

When searching for a spare part, symbols used by various manufacturers can be helpful. For the presented variant, the HYDRON data sheet provides:

• Rastelli-Raccordi: 34.67.24.16,
• Vitillo: ARGG2416,
• type designation: 1B-16-24,
• alternative designation: XGR 1 1/2"-1".

Catalog designations facilitate the identification of an equivalent; however, the full technical parameters must always be compared before using a replacement.

How to select the right BSP 1" / 1.1/2" fitting?

Before ordering, thoroughly check both installation elements that are to be connected. In the case of this model, the most important parameters are:

• first side: BSP 1" male,
• second side: BSP 1.1/2" male,
• outer diameter of BSP 1": about 33.0-33.2 mm,
• outer diameter of BSP 1.1/2": about 47.4-47.8 mm,
• sealing system: 60° cone,
• working pressure: maximum 125 bar,
• operating temperature: from -20°C to +120°C,
• material: free-cutting steel,
• surface protection: zinc plating with white passivation.

If the fitting is selected based on a component removed from an older machine, it is worth measuring both threads with a caliper and additionally checking their pitch. This is especially important when identifying larger inch connections.

Hose selection for large BSP connections

When manufacturing a complete hydraulic hose assembly, the thread size alone is not enough. You must also select the hose inner diameter, hose construction, required working pressure, length, and appropriate fittings.

To prepare the appropriate configuration, you can use the HYDRON hydraulic hose configurator. It allows you to select the hose parameters and fittings for a specific machine or installation.

What to watch out for during assembly?

Before making a connection, check the condition of the threads and sealing surfaces. They should be clean and free of mechanical damage.

If the fitting tightens with unusually high resistance even during the first few turns, do not force it. This may indicate the use of a different size, pitch, or an incompatible thread standard.

After installation and commissioning of the system, the tightness of the connection should be checked under conditions consistent with the service procedure of the given system.

Hydraulic fittings at HYDRON

In the HYDRON offer, you will find a wide selection of hydraulic fittings for the construction, repair, and modernization of power hydraulic systems. BSP, BSPT, JIC/UNF, ORFS, NPT connectors, and various metric connections are available.

Frequently Asked Questions

What threads does the fitting have?

On one side, there is a BSP 1" male thread, and on the other, a BSP 1.1/2" male thread.

Is it a reducing fitting?

Yes. The fitting enables a direct transition between a BSP 1" and a larger BSP 1.1/2".

What is the maximum working pressure?

The maximum working pressure specified for this product is 125 bar.

What material is the fitting made of?

The body is made of free-cutting steel protected by zinc plating with white passivation.

What sealing cone is used?

The fitting features a 60° sealing cone.

What is the diameter of the BSP 1" thread?

For the BSP 1" male thread, the product data sheet specifies approximately 33.0-33.2 mm.

What is the diameter of the BSP 1.1/2"?

For the BSP 1.1/2" male thread, the product data sheet specifies approximately 47.4-47.8 mm.

Does the BSP 1" have an actual diameter of 25.4 mm?

No. The 1" designation is nominal. The actual outer diameter of the BSP 1" thread is approximately 33 mm.

Does the BSP 1.1/2" have a diameter of 38.1 mm?

No. This is a nominal designation for a pipe thread. In the presented product, the actual outer diameter is approximately 47.4-47.8 mm.

What is the operating temperature range?

The temperature range specified for the fitting is from -20°C to +120°C.

What medium is specified for the product?

In the product description, hydraulic oil is indicated as the medium.

Can the fitting be used in a system operating at 160 bar?

The maximum working pressure specified for the product should not be exceeded. For this fitting, it is 125 bar.

Does a larger BSP 1.1/2" thread imply a higher permissible pressure?

No. Connection size and permissible pressure are separate parameters. For this specific product, the maximum value is 125 bar.

What catalog designations help in finding a replacement?

The product data sheet lists the designations 34.67.24.16, ARGG2416, 1B-16-24, and XGR 1 1/2"-1".

Can the fitting be selected based solely on diameter?

No. Measuring with a caliper is very helpful, but you must also check the thread pitch, BSP standard, and the design of the sealing surface.

What should I do if I am not sure about the thread type?

It is best to measure both connections, check the thread pitches, and compare the component with the machine documentation or a thread gauge. In case of doubt, it is worth using HYDRON technical support before ordering.