3B BSP Female 60 Degree Cone Hydraulic Adapter — 3B Adapter

1. What a 3B Adapter Does

The 3B adapter is a straight BSP female-to-BSP female conversion fitting with a 60 degree cone seat at both ends. Connection 1 and Connection 2 are both female ports machined with ISO 228-1 G parallel pipe thread, so the part joins two male stud ends that each present a matching 60 degree cone.

This adapter performs no useful work unless both female ends match the male stud ends they receive in thread form, thread pitch and cone angle. Matching both ends exactly is the precondition for eliminating leakage at the conversion point, because the 60 degree cone is the sealing surface.

The sealing principle of this series is the 60 degree cone seat. The male stud end carrying the mating cone seats metal-to-metal against the cone inside each female end, and that contact forms the pressure-tight joint. A bonded seal, an O-ring and thread sealant are not part of the 3B sealing concept, and the joint never depends on the thread flanks to seal.

2. 3B Specifications

The specification below presents the two ends of the 3B adapter as mirrored blocks, so a buyer can read off which port each end serves. Both blocks use the same thread family and the same sealing method, because this is a symmetrical female-to-female series.

2.1 Connection 1 — BSP female, 60 degree cone seat (E end)

• Thread standard: ISO 228-1, pipe threads where pressure-tight joints are not made on the threads.
• Thread family: British Standard Pipe Parallel (BSPP / G).
• Gender: female.
• Size range: G1/8″x28 up to G2″x11.
• Sealing method: 60 degree cone seat.
• Mating port standard: ISO 1179 (BSPP port and stud end with 60 degree cone seat).

2.2 Connection 2 — BSP female, 60 degree cone seat (F end)

• Thread standard: ISO 228-1.
• Thread family: British Standard Pipe Parallel (BSPP / G).
• Gender: female.
• Size range: G1/8″x28 up to G2″x11.
• Sealing method: 60 degree cone seat.
• Mating port standard: ISO 1179.
• Note: on this series the F end thread is always equal to or larger than the E end thread.

2.3 Construction and Materials

The body is machined from bar stock on CNC lathes as a single piece, with no brazed or welded joint in the pressure path. Body material options are carbon steel, 304 stainless steel, 316 stainless steel and brass. Carbon steel bodies are supplied with trivalent chromium zinc plating (Cr3+) or zinc-nickel plating; stainless steel bodies are supplied bare.

Because the joint seals metal-to-metal on the cone, the series contains no elastomeric seal of its own and there is no seal material to select for the adapter body. Where the mating stud end brings its own O-ring or bonded seal into the joint, choose that seal material to suit the fluid and temperature.

Each hexagonal section is turned on the same setup as the threads, so the spanner flats in the table are concentric with the thread axis. Thread gauges and dimensional checks are applied batch by batch before packing.

2.4 Pressure and Temperature

Working pressure for these sizes is confirmed per order by HENGHUA engineering, based on the sealing method, thread size and material selected. There is no single catalogue pressure figure that applies to every row of the table below, because wall thickness and body size change across the range.

The body itself has no elastomer, so its temperature capability follows the fluid, the mating component and the body material. Carbon steel with zinc plating suits general hydraulic service; 304 and 316 stainless steel are the options for corrosive and offshore service. Where a bonded seal or O-ring is present elsewhere in the same joint, these material limits apply:

2.5 Part Number and Dimension Table

E and F are the two female thread callouts, E for Connection 1 and F for Connection 2. A, B, L, S1 and S2 are the body dimensions marked on the drawing above, in millimetres: L is the overall body length, A and B are the two end section lengths, and S1 and S2 are the hex (spanner flat) sizes at the two ends. Thread callouts follow the drawing notation, where G1.1/4″ means G1-1/4″ and G1.1/2″ means G1-1/2″.

3. How to Read a 3B Adapter Part Number

The prefix 3B identifies the series: BSP female to BSP female, straight body, 60 degree cone seat at both ends, ISO 228-1 G thread. The series prefix is followed by one or two size codes that are the BSP size steps of the two ends.

A single code means both ends share one thread size. 3B-08 is therefore G1/2″x14 at both ends. A double code means the two ends differ, and the first code is always the E end while the second code is always the F end.

Worked example from the table: 3B-08-12 has E end G1/2″x14 and F end G3/4″x14, with A 7.5, B 10.9, L 32.5 mm, S1 27 mm and S2 32 mm. This is the row to order when a G1/2″ port has to be converted to accept a G3/4″ male stud end. Suffixes such as -SP, -PK, -WD or a trailing 9 are not used in this series; the 90 degree version of this family is a separate series, and mixing the two prefixes is the most common ordering error.

4. Installation and Fitment

Inspect both female threads and both cone seats before assembly, and reject any part with a nicked cone or a burr on the thread start. Wipe the cone clean and keep it free of paint, dirt and old sealant, because a 60 degree cone seat seals only where the two cones touch.

Start both connections by hand and turn them until the cones touch, then tighten snug and apply the tightening angle specified for the size and material. Do not swing on a short spanner to force a joint that will not seat, and do not add thread sealant as a substitute for a correct cone fit.

Common fitment errors and their symptoms: a BSPT male end forced into the female end damages the parallel thread and leaks along the thread, because a taper thread cannot seat on a 60 degree cone; a cross-threaded start leaks at the first pressure cycle; an over-tightened joint cracks the female end at the hex; and a re-used adapter that has been run loose shows cone brinelling and will not seal again.

5. Applications and Industries

Typical application tags for this series are hydraulic systems, water jetting, oil and gas equipment, industrial equipment, construction machinery, agriculture, marine and material handling. The common thread is a conversion between two BSPP ports that both use the 60 degree cone seat.

Concrete scenarios: a maintenance team converting a machine that carries a G1/2″ male test point to accept a G3/4″ male hose stud, without changing either original port; a repair bench holding one 3B adapter so a damaged female port can be re-terminated without re-machining the housing; a test bench where a female-to-female 60 degree cone joint is needed to join two male stud ends in line; and an OEM assembly line where the adapter is fitted to a manifold before the sub-assembly reaches the test rig.

6. Replacement and Cross-Reference Guide

Identify a replacement by standard and sealing method, never by brand. The 3B is a BSPP female-to-BSPP female part with ISO 228-1 parallel thread and a 60 degree cone seat at each end, so the three things to measure are the thread outside diameter and pitch, the seat type inside each end, and the two thread sizes in order.

Measure these three things before ordering: first, the outside diameter of the male stud end that must enter each female end, and its threads per inch, to confirm both are ISO 228-1 G thread at 28, 19, 14 or 11 threads per inch; second, the seat inside each female end, checking for a 60 degree cone rather than a flat face; third, the count of connections, since a female-to-female straight body is a different part from a female-to-male or elbow body.

7. Ordering, Packaging and Delivery

To order, give the series code and the full part number, both thread sizes, the body material, the plating, and the quantity. For example: series 3B, part number 3B-08-12, E end G1/2″x14, F end G3/4″x14, carbon steel with trivalent chromium zinc plating, 500 pieces.

Packaging is arranged for distributor shelves and for direct-to-line delivery. Parts are protected against thread damage in transit and labelled with the part number and thread sizes. Sample orders are available for validation before a production release, and lead time is confirmed per order once thread sizes, material and quantity are fixed.

8. FAQ

Q1. What is the difference between BSPP and BSPT, and can they be interchanged? BSPP is the parallel thread defined in ISO 228-1, and BSPT is the taper thread defined in ISO 7-1. A BSPP joint seals on a 60 degree cone seat or on a bonded seal at a flat face, while a BSPT joint seals on the thread flanks and needs sealant. They are not interchangeable: a taper male end threaded into this female end will not reach a cone seat and will leak, and the mismatched pitch and taper damage the threads.

Q2. What is the difference between a 60 degree cone seat and a bonded seal, and which should I choose? A 60 degree cone seat forms a metal-to-metal seal between two cones and carries no elastomer, so it is the choice for high temperature and for joints that must not rely on a soft material. A bonded seal is a metal washer with a bonded elastomer ring that seals on a flat face and tolerates a slightly imperfect face. Choose the cone seat when the mating stud end has a cone, and a bonded seal when the mating port has a flat face.

Q3. How do I identify the correct 3B size? Read the thread callout on both mating stud ends. If both ends are the same size, order the single-code part number, for example 3B-08 for G1/2″x14 at both ends. If they differ, order the double-code part number, placing the smaller or first-connection thread first, for example 3B-08-12 for G1/2″x14 to G3/4″x14.

Q4. What seal material should I select for my fluid and temperature? The 3B adapter has no elastomer at the seat, so the material decision is the body material: carbon steel with zinc plating for general hydraulic service, or 304 or 316 stainless steel for corrosive and offshore service. Where a bonded seal or O-ring is used elsewhere in the joint, NBR covers approximately -30°C to +100°C, FKM approximately -20°C to +200°C, and EPDM approximately -40°C to +120°C.

Q5. How is the working pressure of this adapter determined? Working pressure for these sizes is confirmed per order by HENGHUA engineering, based on the sealing method, thread size and material selected. It is governed by the size and wall thickness of the body and by the pressure class of the mating port, so a single figure cannot be published for every row. Send the sizes and the expected system pressure with your inquiry and the confirmation is issued with the quotation.

Q6. What is the minimum order quantity and can I get samples? Minimum order quantity depends on the size and the material, and is confirmed with the quotation. Samples are available for validation, and for stainless steel sizes a sample is the normal way to confirm thread fit and cone contact before a production order. Send the part number, the intended fluid and the annual quantity, and the sample and lead time are confirmed together.

Q7. Can this adapter be re-used after it has been in service? A 3B adapter can normally be re-used if the cone seats are unmarked and the threads are undamaged. Inspect both cones for brinelling or a bright ring after removal; if the cone has been deformed by over-tightening, replace the part rather than re-fitting it.

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