Designation Of Threaded Connections; Threaded Connection Rp (Example Rp 1/2); Threaded Connection G (Example G 1/2) - Johnson Pump TG GS2-25 Instruction Manual

3.21.7 Designation of threaded connections.

To make clear what sealing type of threaded connection is provided we denominate them according to
standards ISO 7/1 and ISO 228/1 as follows.

3.21.7.1 Threaded connection Rp (example Rp 1/2)

If no flattened sealing face is provided we call the connection Rp accordingly ISO 7/1. This
connection has to be sealed in the thread. The plugs or pipe connections must be provided with
conical thread according to ISO 7/1 external thread (example ISO 7/1 – R1/2).
Conical plug
ISO 7/1 - R1/2

3.21.7.2 Threaded connection G (example G 1/2)

If the threaded connection is provided of a flattened sealing face we call it G according ISO 228/1.
This connection can be sealed by a gasket. The plugs or pipe connections must be provided with a
sealing collar and cylindrical external thread according to ISO 228/1 (Example ISO 228/1 - G1/2).
Plugs or pipe connections provided with conical thread according to ISO 7/1 external thread
(example ISO 7/1 – R1/2) can also be used.
Plug with collar
ISO 228/1 - G1/2
48
Conical pipe end
ISO 7/1 - R1/2
ISO 7/1
Internal
thread
External
thread
Conical pipe end
ISO 7/1 - R1/2
Type
Cynlindrical (parallel)
Always conical
(tappered)
ISO 228/1 Clearance class
Internal
Only one class
thread
Class A
(standard)
External
thread
Class B
(extra clearance)
ISO 7/1 Type
External Always conical
thread (tappered)
A.0500.501 – IM-TGGS/05.01 EN (03/2013)
Symbol Example
Rp ISO 7/1 – Rp 1/2
R ISO 7/1 – R 1/2
Symbol Example
G ISO 228/1 – G 1/2
G ISO 228/1 – G 1/2
G...B ISO 228/1 – G 1/2 B
Symbol Example
R ISO 7/1 – R 1/2