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REV. STV20110519
2.1.1 Valve housing to actuator connection
The valve housing and actuator are connected with either a hygienic clamp union or bolts, as
indicated below:
Size
12
(1/2”):
TC CLAMP 1"/ 1.5"
Size
25
(1”):
TC CLAMP 2.5"
Size
38
(1 ½”):
TC CLAMP 2.5"
Size
51
(2”):
M8x16mm. ( 4pcs.)
Size
76
(3”):
M8x16mm. ( 4pcs.)
2.1.2 Diaphragm connection
The diaphragm connection to the actuator stem is made by means of a pressure plate or threaded
connection depending on valve size and diaphragm material.
For valves 12 (1/2”), 25 (1”), and 38 (1 1/2”), with EPDM and Silicone diaphragms, the
diaphragm is attached by means of a pressure plate installed in the stem, type 1 or 2. As a
standard, the actuators are supplied with a type 1 pressure plate. When using type 1, the
diaphragm is pressed into the plate. The type 2 pressure plate is provided as an option and
recommended when it is expected that the valve would remain in the closed position for prolong
periods of time and would also be subject to steaming. The diaphragm screws into the type 2
pressure plate.
The pressure plates are interchangeable. Refer to Figure 13 for details on how to replace a type 1
for a type 2.
Figure 12: Diaphragm Connection Types
No Pressure Plate Pressure Plate Type 1
Pressure Plate Type 2
