Masoneilan 84003 Series SteamForm Installation Guide | 15
Copyright 2020 Baker Hughes Company. All rights reserved.
Response Time and Stroke Speed
Response time is critical in preventing steam and
condensate losses from the system due to lifting of safety
valves. These system requirements are specified during
the early stages of the plant design and must account for
both the lag time of the temperature control system and
the opening speed of the SteamForm valve.
The lag time resulting from the response of the
temperature sensing system can be reduced through the
use of a dual method control system. This dual method
system uses a feedforward control algorithm to determine
the amount of water required and provides faster acting
temperature response. The addition of a temperature
sensor to this system improves the accuracy of the
temperature control by “trimming” the variability once the
downstream profile stabilizes.
Stroke speed must be considered in this system, as rapid
response time cannot be achieved with all methods of
actuation. Stroke speeds using a pneumatic controller
are often limited to the 2–3 second ranges. For faster
response time, the use of electrohydraulic actuation
can be considered. Please consult a Baker Hughes
Masoneilan Certified Technician for a recommendation
for each application.
Start-Up And Commissioning
In addition to specifying the steam conditioning valves,
a start-up procedure must also be defined up front in the
design process. Proper cleansing of the steam line and
water lines is essential to ensuring performance when the
plant becomes operational. Debris left in line can remove
the machined finish from a shutoff surface or block the
orifice of a control element or spray nozzle. To protect the
integrity of the operational trim, Baker Hughes strongly
encourages the purchase of sacrificial start-up trim, which
is used to divert debris away from all critical surfaces.
Installation of the start-up trim is shown in Figure 12.
Figure 12: Start-up trim
System Blow Down and Cleaning
With the SteamForm start-up trim installed and the spray
nozzles removed, all debris, scale, and unintended
substances must be flushed from the steam and water
lines.
Conducting this cleaning procedure with operating trim
installed can result in several possible scenarios requiring
components replacement or repair. For instance, damage
to a finished surface can result in premature erosion
that eventually leads to unwanted leakage and unstable
control. Debris lodged in the operating trim can also
result in loss of flow capacity or plug sticking because
of debris induced galling of the plug against a control
surface.
See SteamForm Instruction Manual GEA31013A for
detailed instructions for valve installation and cleaning
process.
CAUTION :
Any damage caused to the valve during
cleaning or installation process is not Baker Hughes’s
responsibility. Failure to follow instructions provided in
the Manual GEA31013A will violate the valve warranty
agreement.
