1. BSP Fitting (BSP Hydraulic Fittings)
Thread standard: BSP is divided into BSPP (parallel threads, code G) and BSPT (conical threads, code R)
Sealing principle:
BSPP: The seal is achieved by using a combination of gaskets (metal gasket + rubber) or a 60° internal conical surface.
BSPT: It relies on the self-cone of the thread for interference sealing, and requires the use of sealant or PTFE tape.
Applicable scenarios
-Industrial machinery, machine tool hydraulic systems
-General-purpose low and medium pressure lines
Selection Tip: The BSPP and NPT threads cannot be interchanged. The tooth profiles are different (55° vs 60°). Forceful insertion may result in oil leakage or damage to the ports.
2. 22611 British D-Type Fittings
Thread standard: BSPP (G thread) with 30° external cone sealing
Sealing principle: 30° outer cone of the fitting mates with the 30° inner cone of the mating component to form metal-to-metal hard seal. No gasket required.
Applicable scenarios
-Construction machinery, agricultural machinery hydraulic pipelines
-Medium and high pressure hydraulic hose assemblies widely used in Southeast Asia and Middle East markets
-Replacement for original BSP standard hydraulic connectors
Selection Tip: Strictly match 30° inner cone counterpart. Do not assemble with 60° cone ports, otherwise oil leakage will occur under pressure.
3. 22211 British A-Type Fittings
Thread standard: BSPP (G thread)
Sealing principle: Flat face sealing with combined metal-rubber washer. The compression of the gasket realizes sealing.
Applicable scenarios
-General engineering machinery hydraulic circuits
-Low & medium pressure hydraulic hose connections
-Convenient maintenance and easy on-site assembly
Selection Tip: The sealing effect depends on intact gaskets. Replace the gasket once disassembled to avoid leakage. Cannot be used without a sealing washer.
4. 29611 BSP C-Type Fittings
Thread standard: BSPP (G thread) with 60° external cone sealing
Sealing principle: 60° outer cone metal hard sealing, matched with 60° internal cone cavity.
Applicable scenarios
-Heavy-duty construction machinery, mining equipment hydraulic hosesHigh pressure hydraulic pipeline assembly, popular in Africa and Southeast Asia aftermarket
Selection Tip: Distinguish clearly from 22611 (30° cone). The two types are not interchangeable. Mis-matching will cause sealing failure and pressure runaway.
General Summary
All 22611, 22211, 29611 adopt BSPP . The core difference lies in the sealing surface angle and structure.
When receiving customer inquiries, confirm the mating sealing structure first before confirming the model, to avoid wrong delivery.
