Series 651  MAINTENANCE 
 
605451EC  Edition 2014-07-10  75/
 
7.2.1  Replacement of isolation seals and cleaning 
7.2.1.1  Required tools 
 
• 
Allen Wrench 5 mm 
• 
Open end wrench 13 mm 
• 
O-ring removal tool (see chapter: Accessories) 
• 
VAT cleaning tool (see chapter: Accessories) 
• 
Vacuum grease (see chapter: Spare parts) 
• 
Clean room wiper 
• 
Isopropyl alcohol 
 
 
 
Electrical power and compressed air is required to perform steps 2 to 9 during 
disassembly respectively 9 to 2 during assembly. 
 
Description 
Required tool 
1.  Vent both valve chambers. 
2.  Open the 4 bonnet screws and 
remove valve bonnet. 
 
Allen wrench 
5 mm 
3.  Open the valve  
Caution: Pay attention plate moves 
out! 
4.  Unfasten mounting screw for 
pendulum plate. (For reinstall the 
pendulum plate, tighten the 
mounting screw to block.) 
5.  Remove pendulum plate. 
 
      mounting screw 
      for pendulum plate 
 
Open end wrench 
13 mm