Installation, Operation and Maintenance Manual
MAN 689 Rev. 6
June 2021
General Warnings
XXX
K
-
YYYYY
-
ZZZZ
-
F
S
C
Actuator series
Scotch yoke mechanism size
Yoke shape
C
Canted
S
Symmetric
Spring cartridge size
Cylinder size
Internal diameter in mm
Spring action
CL
Closing
OP
Opening
Service
Blank
Standard
QA
Quick-acting
Manual override
Blank
No manual override
MHP
Manual handpump
MHW
Manual handwheel
MRHW
Manual reduced handwheel
The expected lifetime of actuator is approximately 25 years.
Table 1.
Single Acting Low Pressure Pneumatic Actuators - Coding System
3
Section 1: General Warnings
The housing of the scotch yoke mechanism has a flange with threaded holes to fix the
actuator to the valve either directly or, if required, with the interposition of an adaptor
flange or a mounting bracket.
The actuator yoke has a hole with keyways suitable for the assembly of an insert bush or a
stem extension. Their internal hole is machined (by Biffi or at Customer's care), according
to the shape and dimensions of the valve stem.
Biffi can supply different types of control system following Customer's requirements.