7
KTM
VIRGO SERIES N TRUNNION MOUNTED BALL VALVES
INSTALLATION, OPERATION AND MAINTENANCE INSTRUCTIONS
7 PREVENTIVE / PERIODIC MAINTENANCE
Preventive / periodic maintenance is essential
as the failure to do so may result in inadequate
performance of the valve or also failures like
seat leakage, environmental leakage, increased
torque, jerky operation etc.
All valves in operation should be periodically
inspected thoroughly to evaluate the condition
of ball, seats and seals as these parts are
subject to normal wear and tear. The frequency
of inspection depends upon the severity of
service conditions and location of the valve
and should be conducted during partial or
total shutdown.
Special attention is to be paid to inspect for
damage and / or wear due to corrosion or
erosion.
Periodic inspection of valve typically includes
following activities:
• Inspection for any visible defect or failure
such as packing or body joint leakage
• Tightening of bolts/nuts to recommended
torques
• Valve stroking to prevent jamming and
corrosion every six months
Section 11 describes the procedure for
disassembly and reassembly of the valve.
Once a valve is refurbished / repaired it should
undergo a complete set of tests to make sure
that the valve is fit to use for the intended
working conditions. Hydrostatic or Pneumatic
tests should be carried out as per the
specifications relevant to the valve.
Gear operators are packed with grease.
It is recommended that the grease should
be changed after approximately 5-7 years
if operated frequently or after 10-12 years
if operated infrequently. Contact factory for
appropriate grease grades if grease needs
to be changed
8 POSSIBLE MISUSE OF BALL VALVE
Sr. No.
Possible misuse
Actions to prevent misuse
1
Exceeding the pressure and / or temperature limits
of the valve.
Do not exceed pressure and / or temperature limits mentioned on name plate affixed to the valve.
2
Valve material not suitable for service fluid.
Check Tag number (as applicable) and ensure correct valve is used as per process diagram.
Verify valve material mentioned on Name plate is suitable with service fluid.
3
Use for control application.
These ball valves are designed for on/off application and should not be used for control / throttling.
4
Mounting of valve upside down.
Follow ‘Installation’ section of this document.
5
Wrong installation in case of uni-directional valve.
Verify flow direction on valve body or on additional plate affixed to valve.
6
Use of improper actuator when customer automates
valve on site.
Contact factory for correct sizing of actuator.
7
Opening/closing of valve by using inappropriate
extensions like pipes/bars etc.
Operate valve only with levers, gear operator, hand wheel or actuator provided / recommended
by Emerson.
8
Any modification by customer in valve e.g. drilling,
tapping, change of valve ends etc.
Unauthorized modifications are not allowed. Modification voids warranty. Contact factory if any such
case arises.
9
Testing the valve with water without corrosion
inhibitor.
Corrosion inhibitor shall be used to prevent corrosion of valve components. Requirements of
international standards such as API 6D, API 598, BS EN 12266 etc. should be followed.
10
Inadequate draining and drying of valve after
hydro test.
When valves are hydro tested onsite, they shall be drained and dried completely before installing on
pipeline to prevent corrosion of parts and contamination of service fluid.
11
Not using lock open/close feature.
Ensure to use this provision (as applicable) based on process requirement.
12
Improper long term storage.
For long term storage and preservation of valves at site refer Emerson procedure QAC/KM-028.
Contact Factory.
13
Damage to valve fittings during handling.
Follow handling instructions.
