Spirax Sarco ABV21i, Installation And Maintenance Instructions Manual

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IM-P405-46 EMM Issue 5 6
2. General product information
2.1 General description
The Spirax Sarco ABV21i and ABV40i are one piece end entry, reduced bore ball valves
having ISO mounting as standard. They are fitted with a 90 ° rotary spring return pneumatic
actuator, and a limit switch box. They are used in conjunction with a Spirax Sarco blowdown
timer to provide timed control of bottom blowdown, ensuring that the recommended boiler
blowdown cycles occur with minimum heat loss, avoiding duplication or omission.
The valve is suitable for a maximum pressure of 17.25 bar g @ 208 °C (250 psi g at 406 °F).
A NAMUR (VDI / VDE 3845) solenoid valve is also required, and may be selected from the
Spirax Sarco MV range. Alternatively, an air supply (maximum pressure DN25 8 bar (116 psi),
DN32 to DN65 6 bar (87 psi)) may be connected directly to the actuator port 'A' ( ¼ " BSP), for
applications where it is necessary to install the solenoid valve remote from the actuator.
A standard ¼ " BSP 3-way solenoid valve may also be used.
ISO mounting
The integral ISO body mounting allows the valve to be automated without losing seal intregrity,
as the body does not require disassembly.
2.2 Product availability
Valve type Valve size Actuator Switch box
ABV21i and ABV40i
DN25 BVA315S /14 LSB31
DN32 BVA320S /14 LSB31
DN40
BVA325S /14 LSB31
DN50 BVA325S /14 LSB31
DN65 BVA330S /14 LSB31
2.3 Actuator
The actuator uses a rack and pinion system with a quarter-turn operation. A position indicator
is fitted to the top of the pinion shaft, below the switch box. BVA actuators are factory
lubricated, and do not require a lubricated air supply. The air must, however, be dry and clean.
Any other non-corrosive gas can be used as the operating medium.
2.4 Switch box
LSB limit switch boxes are normally used for indicating valve open or valve closed position.
They also allow switching points to be adjustable over the full range of actuators. There is an
open / closed valve position indicator mounted at the end of the switch box axis, at the top
of the cover. LSB's include a stainless steel linkage kit for direct mounting to BVA300 series
actuators.