IG Blower Requirements
As per SOLAS Ch. II-2/ Regulation 62, the IG blower requirementsare as follows:
1) Minimum 2 number of blower to be fitted in I.G system.
2) The capacity of each blower must be 1.25 times the overall capacity of the cargo discharge system fitted on board. This is to ensure that Inert Gas is always present in the cargo hold.
3) Only 1 blower may be permitted by the administration if it fulfills the IG blower requirements stated in above point i.e. capacity must be 1.25 time cargo pumps and required spares are always available.
4) A shut off arrangement must be provided in the suction and discharge connection side of the blowers.
5) Generally the blowers are used for gas freeing hence an air inlet with blanking arrangement must be provided. At normal operation, blanking arrangement is to be secured.
Also read: What is the EMS guide?
6) Cargo tanks are pressure tested at 2500 mm water gauge and 700mm water gauge on the vacuum side. The blower pressure must not exceed the test pressure else the tank will get damage.
7) Minimum pressure to be maintained by blower is 200 mm water gauge in cargo tank.
8) There must be high temperature alarm (around 65 deg C) and a high temperature trip ( around 75 deg C) to safeguard the blower.
9) The driving media for blower can be either steam or electrical power.
10) The blowers must be located at aft of the cargo tanks and cargo pump room of the ship.
Ref: SOLAS Consolidated edition & MSC Circ. 387- Revised guidelines for IG system
