SIL Safety Manual
SM-025-GVO Rev. 0
November 2017
17
Section 8: Periodic Test and Maintenance Requirements
Periodic Test and Maintenance Requirements
The parameters to be measured depends upon the partial stroke test system available.
Instruments / equipment to be used for the test:
The Partial Stroke Test can be executed in the following way:
1.
Using commercial PST device, measuring/verifying:
a.
Measurement of linear position as function of time (pressure measure-
ment is optional)
b.
Measurement of cylinder chamber pressure as function of time
c.
Verification of final position achievement in the established maximum
time.
2.
By means of Logic Solver, measuring/verifying:
a.
Measurement of linear position as function of time (pressure measure-
ment is optional)
b.
Measurement of cylinder chamber pressure as function of time
c.
Verification of final position achievement in the established maximum
time.
3.
By means of a manual PST system manufactured by Emerson (slightly different sys-
tems can be available: please make reference to the documentation of the specific
project)
Table 5.
Quality
Instruments / equipment
Automatic Procedure
Manual Procedure
Linear position of the shaft
Case A: use of a Logic Solver:
1. Limit switches box, or
4÷20 mA position transmitter
2. Digital Input Module /
Analog Input Module
included in the Logic Solver
3. Application SW function
(to compare the actual trend
with the one stored during
SAT)
Case B: use of a PST device:
4. Limit switches box, or
4÷20 mA position transmitter
5. PST device with integrate
SW function
1. Limit switches box, with
visual indication
2. Skilled and trained personnel
Time necessary to reach the
final position
As above
1. Chronometer
2. Skilled and trained personnel
