Bladder Tank Proportioning System – PSL

Bladder Tanks are positive displacement pro-portioning systems made of a tank and an in-line mixer. The tank is equipped with a bladder that is used to hold the foam concentrate and a mixer is directly piped to the bladder tank. When in operation, water flows into the mixer creating a pressure differential. This pressure drop together with the membrane compression allows foam concentrate to be injected into the water stream.

The system works until the reserve foam concentrate inside the membrane is not exhausted and the tank is filled with water. The bladder tanks can be equipped with two types of mixers named Type A and Type B. The type A is a standard foam proportioner that allows a mixing ratio being constant over a 1:6 water flow rate range. The Type B instead is a mixer also known as a wide range proportioner and therefore capable of performing over a wider flow range.

Bladder tanks are manufactured according to ASME or EN standards with variable thicknesses according to the client requirements for design pressure and corrosion allowance. Every unit is available in a horizontal (PSLO) or vertical (PSLV) configuration and is customized according to client specifications including accessories such as: double tank systems (2xPSLV), ladders for easy access to man hole(s), deluge or remote controlled valves for foam system automation, manual or electric filling pumps, skidded platforms and special painting procedures.

The Bladder tank can also be manufactured with foam concentrate to be contained inside (SIM) or outside (SEM) the bladder.

Technical characteristics

Version in carbon steel: (MIXC)

• Body in carbon steel ASTM A 106
• Flange ANSI or UNI, in carbon steel
• Calibrated water diaphragm in AISI 316
• Concentrated foam calibrated diaphragm in AISI 316 with check valve
• Water and concentrated foam ball valves in carbon steel
• Water drain valves
• Brass body
• Chromium plated brass ball
• PTFE seal
• AISI 316 pressure gauge
• Working pressure 12 bar
• Design pressure 16 bar
• Test pressure 24 bar
• Name plate: aluminium

Version in stainless steel: (MIXI)

• Body in stainless steel AISI316
• Flange ANSI or UNI, in stainless steel AISI 316
• Calibrated water diaphragm in AISI 316
• Concentrated foam calibrated diaphragm in AISI 316 with check valve
• Water and concentrated foam ball valves in stainless steel
• Water drain valves
• Brass body
• Chromium plated brass ball
• PTFE seal
• AISI 316 pressure gauge
• Working pressure 12 bar
• Design pressure 16 bar
• Test pressure 24 bar
• Name plate: aluminium

WIDE RANGE MIXER – TYPE B

Technical characteristics

Version in carbon steel: (MARC)

• Body in bronze
• Inner Parts: AISI 316
• Max working pressure 16 bar
• Design pressure 16 bar
• Test pressure 24 bar
• Natural surface fishing
• Piping in carbon steel
• Flange ANSI or UNI, in carbon steel
• Water and concentrated foam ball valves in carbon steel
• Water drain valves
• Brass body
• Chromium plated brass ball
• PTFE seal

Version in stainless steel: (MARI)

• Body in bronze
• Inner Parts: AISI 316
• Max working pressure 16 bar
• Design pressure 16 bar
• Test pressure 24 bar
• Natural surface fishing
• Piping in stainless steel AISI316
• Flange ANSI or UNI, in stainless steel AISI 316
• Water and concentrated foam ball valves in stainless steel
• Water drain valves
• Brass body
• Chromium plated brass ball
• PTFE seal