6
5.4.4 Welding fillers
Filler match-up table
 Material to       Suitable welding filler 
 be welded  1.4316  1.4430  1.4440  1.4519 
 1.4301  x       
 1.4306  x       
 1.4401    x     
 1.4404    x     
 1.4435    x  x  x 
 1.4571    x  x
5.4.5 Final treatment of weld
  Interior area
  Final treatment of weld not required. Surface quality 
can be improved at accessible points by grinding.
  Exterior areas
  Final treatment process:     
  Pickling– brushing– grinding- polishing
5.5  Cleaning 
  Clean entire valve thoroughly before installing.
5.6  Installation 
  Install according to installation instructions.
6  DISASSEMBLY AND ASSEMBLY
  (see fig. 2)
6.1  Installation 
  To remove the complete valve, separable connections 
must be provided in the vicinity of the valve connections a and b.   
We recommend following distances from the valve: 
  Product inlet (a) :  1 x diameter 
  Product outlet (b) :  6 x diameter
7  DISASSEMBLY
  Please observe separate documentation for disas-
sembly of the actuator.
  CAUTION: 
  Before disassembly:
  depressurise the line to atmospheric pressure and 
drain all fluid from the valve, close-off the supply air.
  Valves with air-to-open actuators: tension the actua-
tor springs using top handwheel or by applying sup-
ply air under the membrane.
  WARNING: Failure to do this will cause the valve bon-
net to spring-out when the clamp is released due to 
the spring pressure acting between the plug and seat. 
  Observe electrical connection voltage, as necessary 
switch off power supply.
7.1  Disconnect pneumatic and electrical feed lines. 
7.2  On air-to-open / spring-to-close actuators tension 
actuator springs.
7.3  Remove actuator 
Remove the coupling between the actuator stem and 
the plug stem (3). Loosen the slotted nut (M38x1.5) 
on the valve bonnet (2) and remove the actuator. 
7.4  Release the tension on actuator springs.
7.5  Loosen and remove the TC clamp (4).
7.6  Remove the bonnet assy (2) from the body (1).
  CAUTION: To avoid damage to the O-ring (6) do not 
turn the bonnet.
7.7  Pull the plug/stem (3) out of the bonnet (2). 
7.8  Carefully remove the wiper (5).
7.9  Remove the O-Ring (7) which serves as the stem seal.
7.10 Remove the body O-Ring (6)
7.11 Remove the PTFE-guide (8) from the bonnet (2).
8  ASSEMBLY
  Please observe separate documentation for assembly 
of the actuator.
  Before assembly: 
  Thoroughly clean all surfaces. 
8.1  Place O-Ring (7) in the bonnet (2).
8.2  Place the wiper (5) in the bonnet (2).
8.3  Place the housing gasket O-Ring (6) in the shoulder 
provided on the bonnet (2).
8.4  Insert the PTFE-guide (8) carefully in the bonnet (2) 
and ensure it is seated correctly to prevent damage to 
the guide.
8.5  Insert the plug/stem (3) into the bonnet (2) .
8.6  Place the bonnet assy. (2) on the body (1).
  CAUTION: Insert the body straight. Ensure that the 
  O-Ring (6) is seated correctly in the groove in the bon-
net. To avoid damage to the O-ring (6) do not rotate 
the bonnet.
8.7  Ensure that the bonnet is seated correctly on the body 
without a gap between the two. Replace the TC clamp 
(3) and tighten securely.
8.8  On air-to-open /spring-to-close apply supply pressure 
to move actuator to half stroke.
  WARNING: If the actuator is not moved to half stroke 
the plug can contact the body when assembling and 
damage the seating faces and/or the valve body.
8.9  Mount the actuator on the valve and secure with slotted nut (M38x1,5).
8.10 Attach the coupling between valve and actuator.
8.11 Release tension on the actuator springs.
8.12 Reconnect pneumatic and electrical feed lines and 
prepare the valve for cleaning.