INTRODUCTION
The foam bladder tank is the main unit of the foam extinguishing system. The foam tank and the low/medium expansion foam generator construct the low/medium foam spraying system. It can also construct the high expansion total flooding extinguishing system with high expansion foam generator. It aims at fire of class A and class B, especially for fire of class B. The foam bladder tank mainly applied in occasions such as places where inflammable liquid was produced, stored and  transported. It is especially suitable to put out fire caused by inflammable liquid tank or large scale of spill fire.
PRINCIPLE
The device consists of pressure tank, bladder, proportioner, pressure gauge, valves and pipeline. A pump is needed to supply pressurized water. When pressurized water flow though proportioner, a small part of water (3%-6%) flow into tank from branch pipe to press the bladder to swap out equal foam concentrate and then mix with another part of water (97%-93%) to form foam solution in proportioner and provide to foam generator.

PARAMETERS

INSTALLATION
Device should be installed at places with shelter to avoid sun and rain. Ambient temperature should be within 40°C and leave enough space  for operation. Device should be  installed at concrete floor and fastened with anchor nuts.
Do the hydraulic test after installing. Open  the tank vent valve first  then fill water into bladder from concentrate draining pipe. Then close  tank  vent  valve  when bladder is full  of water . Pressurize the system and keeping for 10 minutes when pressure gets test pressure, tank should have no leakage. Close water inlet valve and open water  drainage valve  and concentrate drainage valve to drain water away in  tank and  bladder.  (We will do this  test when products leave the 
factory)

OPERATION
1)  Fill Foam Concentrate
Close  water inlet valve and concentrate outlet valve, then  fill  foam concentrate slowly from feed inlet (also can fill foam concentrate from concentrate draining pipe). Make sure bladder vent valve  is open  if  fill  foam concentrate from concentrate draining  pipe. Stop the pump now and then to avoid bladder burst if air in bladder can't  be vented  timely. Foam  concentrate should come from the same manufacturer and the same type. Close feed inlet when finished filling foam concentrate. Close  water draining valve  (there should be no water flow out  at  this time), tank vent valve and bladder vent valve. Open water draining valve 30 minutes later, it indicates that the bladder is undamaged if there is no foam concentrate flow out from water draining pipe.
2)  Operation of The Device
①  Start water pump to supply pressurized water for the device (biggest working pressure is 
1.2MPa)
②  Open water inlet valve and concentrate outlet valve to supply foam concentrate to pipeline
(proportioner), keep other valves closed.
③    Close  water  inlet valve and concentrate outlet valve to stop supply foam concentrate 
when finished working. 
④  Keep the pump working for a while to wash pipeline with fresh water .
⑤  Open tank vent valve and bladder vent valve to relieve pressure. Then close all the valves 
to set the tank in standby mode.
MAINTENANCE

①  To full fill the tank timely after using every time (foam concentrate should be from the same manufacture and the same type)
②  Check the surface of the tank and bladder regularly to find out if there are any leakage and corrosion and check all the valves if they work flexibly. Deal with them if there are any problems.
③  Check the foam concentrate regularly to find out if it is deteriorative. Change it if it is.