Gestra blowdown valve is produced with high quality, resulting in maximum boiler safety and long-term operating time. This type of valve functions to control the concentration of solids / total dissolved (TDS) in the boiler. We offer Gestra blowdown valve with the following types. This briefly produces "vacuum" at the bottom of the boiler. The resulting suction removes settled sediment on the floor of the boiler, also known as boiler sludge, from the boiler. The blowdown action is only effective for the first two seconds. Longer opening times lead to water losses. The boiler pressure supports the closing force of the MPA valve spring, so that the valve closes reliably. The primary area of use is steam boiler plants. The intermittent blowdown action of the valves is triggered by controls such as the TA 7, for example. The control consists of an electronic cycling timer, a three-way solenoid valve and a strainer. When the intermittent blowdown valve opens, the large cross-sectional area of the orifice creates a suction effect, giving a short-term high water flow which will discharge the precipitated sludge and sediments. Type PA valves are intended for manual operation.

For the blowdown process, the valve is opened fully by hand with the lever for around two to three seconds. The spring-loaded valve cone is forced out of the valve seat. As a result, accumulated sludge and sediments rush out of the open valve. When the manual lever is slowly released the spring forces the valve cone back into the valve seat and the valve is closed rapidly. Type MPA valves are equipped with a diaphragm actuator for automatic operation. Compressed air or pressurised water is used as the control fluid. The diaphragm actuator opens the intermittent blowdown valve to perform a brief blowdown.

Rapid-Action Intermittent Blowdown Valve

• PA 46, PN 40 / CLASS 150 / 300, DN 20-50
• PA 47, PN 63 / CLASS 600, DN 25, 40, 50
• PA 48, PN 100 / CLASS 600, DN 25, 40, 50
• MPA 46, PN 40 / CLASS 150 / 300, DN 20-50 MPA 47, PN 63 / CLASS 600, DN 25, 40, 50
• MPA 48, PN 100 / CLASS 600, DN 25, 40, 50 

Description

The following rapid-action intermittent blowdown valves are installed in pipes to discharge boiler blowdown water:  

• Rapid-action intermittent blowdown valve PA 46, PA 47 or PA 48 (manually operated) n
• Rapid-action intermittent blowdown valve MPA 46, MPA 47 or MPA 48 (automatically operated)

The equipment is designed for discharging boiler blowdown water with non-metallic solids from steam boilers. The equipment may only be used within the admissible pressure and temperature limits, with due consideration of chemical and corrosive influences.

Function

When the intermittent blowdown valve opens, the large cross-sectional area of the orifice creates a suction effect, giving a short-term high water flow which will discharge the precipitated sludge and sediments. Type PA valves are intended for manual operation. For the blowdown process, the valve is opened fully by hand with the lever for around two to three seconds. The spring-loaded valve cone is forced out of the valve seat. As a result, accumulated sludge and sediments rush out of the open valve. When the manual lever is slowly released the spring forces the valve cone back into the valve seat and the valve is closed rapidly. Type MPA valves are equipped with a diaphragm actuator for automatic operation. Compressed air or pressurised water is used as the control fluid. The diaphragm actuator opens the intermittent blowdown valve to perform a brief blowdown. The following control units can initiate the opening of the valve:

• the TA program controller, see data sheet,
• the continuous blowdown controller LRR 1-40, LRR 1-52, LRR 1-53, LRR 1-60, see data sheet, 
• the SPECTORcontrol with CAN bus.

Optional extras

• Assembly kit 335130 for retrofitting the actuator of an existing MPA 26 or MPA 27 in a PA 46 or PA 47 to upgrade them to an MPA 46 or MPA 47 (guide bushing with washer and spacer disc)
• Diaphragm actuator 337866 for PA 4x (diaphragm actuator, spacer disc)
• TA program controller for MPA 4x
• Retrofit kit 337980 containing proximity switch for MPA 4x (one limit switch)
• Retrofit kit 337946 containing proximity switch for MPA 4x (two limit switches)
• Emergency lever 337867 for MPA 46/47 and 338073 for MPA 48

End connections

PA 46, MPA 46 

• Flange PN 40, B1 (EN 1092-1) 
• Flange CLASS 150, RF (ASME B 16.5)  
• Flange CLASS 150, RFS (ASME B 16.5)
• Flange CLASS 300, RF (ASME B 16.5)
• Flange CLASS 300, RFS (ASME B 16.5)
• Socket-weld end DIN EN 12760 / ASME B 16.11 CLASS 3000
• Butt-weld end via transition pieces EN 12627, welded joint geometry ISO 9692-1 code no. 1.3 (30° chamfer)
• Butt-weld end via transition pieces Sched 40 (ASME B 16.25, ASME B 36.10)

PA 47, MPA 47

• Flange PN 63, B2 (EN 1092-1)
• Flange CLASS 600 RF (ASME B16.5)
• Flange CLASS 600 RFS (ASME B16.5)
• Socket-weld end DIN EN 12760 / ASME B 16.11 CLASS 3000
• Butt-weld end via transition pieces EN 12627 welded joint geometry ISO 9692-1 code no. 1.3 (30° chamfer)
• Butt-weld end via transition pieces Sched 80 xs (ASME B 16.25, ASME B 36.10)

PA 48, MPA 48

• Flange PN 100, B2 (EN 1092-1)
• Flange CLASS 600 RF (ASME B16.5)
• Flange CLASS 600 RFS (ASME B16.5)
• Socket-weld end DIN EN 12760 / ASME B 16.11 CLASS 3000
• Butt-weld end via transition pieces EN 12627 welded joint geometry ISO 9692-1 code no. 1.3 (30° chamfer)
• Butt-weld end via transition pieces Sched 80 xs (ASME B 16.25, ASME B 36.10)

Rapid-Action Intermittent Blowdown Valve - 

    GESTRA Blowdown Valve PA 46, PN 40 / CLASS 150 / 300, DN 20-50
    GESTRA Blowdown Valve PA 47, PN 63 / CLASS 600, DN 25, 40, 50
    GESTRA Blowdown Valve PA 48, PN 100 / CLASS 600, DN 25, 40, 50
    GESTRA Blowdown Valve MPA 46, PN 40 / CLASS 150 / 300, DN 20-50
    GESTRA Blowdown Valve MPA 47, PN 63 / CLASS 600, DN 25, 40, 50
    GESTRA Blowdown Valve MPA 48, PN 100 / CLASS 600, DN 25, 40, 50

Programme-Controlled Blowdown System - 

    Gestra Automatic Intermittent Blowdown Control TA 7

    Rapid-Action Intermittent Blowdown Valve PA 47 – manual operation
    Rapid-Action Intermittent Blowdown Valve MPA 47 with diaphragm actuator
    Hand lever with clip fastener
    Separate pretensioning
    Wear-protection by downstream, integrated radial assembly level cone
    Tell-tale hole inside the protection pipe
    Leakage control
    Assembly kit 335130 for retrofitting the actuator of an existing MPA 26 or MPA 27 in a PA 46 or PA 47 to upgrade them to an MPA 46 or MPA 47 (guide bushing with washer and spacer disc).
    Diaphragm actuator 337866 for PA 4x (diaphragm actuator, spacer disc).
    TA program controller for MPA 4x n Retrofit kit 337980 containing proximity switch for MPA 4x (one limit switch).
    Retrofit kit 337946 containing proximity switch for MPA 4x (two limit switches).
    Emergency lever 337867 for MPA 46/47 and 338073 for MPA 48.
    The cycling timer PRS 8 is mounted in an appliance plug socket fitted on the three-way solenoid valve.