ADVANTAGE OF TRIPLE OFFSET BUTTERFLY VALVE OVER CONVENTIONAL ON/OFF VALVES
Triple offset Butterfly valve ( which is also called metal seated due to 3rd offset in seating to incorporate metal seating to give zero leakage and tight shut off like rubber sealing) in place of gate , Ball valve , some of the examples given below are as follows:-
1. Replacement in tankages in all the marketing terminals of IOCL ,BPCL ,HPCL across india :- After HPCL Jaipur terminal fire in 2009 , MB Lal committee investigate the fire and gave recommendations (attached) to replace Gate valve and Hammer Blind Valve with metal seated Butterfly valve in ROSOV( Remote Operated Solenoid Valve and MOV (Motor operated Valve) operators .Resultant Metal seated Butterfly valve replaced gate, hammer blind valve in tankages of marketing terminals , since standard metal seated butterfly valve face to face is as per API 609 CAT.B Table 3 ( C) which is short face to face in comparison to Gate valve and to incorporate the short face to face butterfly valve fabrication fabrication of Hydrogen pipeline which itself is a risky and costly affair and also in many cases Blind flange to be mounted on other end of valve for future expansion of pipelines especially in new projects .But there were problems in using short face to face Butterfly valve because Disc will protrude the blind flange on moving it from its resting location . Due to which long pattern metal seated Butterfly valve ( as per API 609 CAT.B TABLE 3 (B) ) with a face to face similar to gate ,Ball valve is used to replace the gate ,ball valve etc in the marketing terminals specially in tankages .
2. Replacement in Fire water Line by Triple Offset Butterfly valve :- As we have seen generally red color fire water line across plants in Refineries, Power, steel sector , gate valve is generally used for the operation of pipe as rubber seated valves are not preferred as due to animosity of Indian weather conditions rubber ,PTFE seat use to get break away (pls refer to Annexure –VII attached) due to regular expansion and contraction from heat & cold conditions. Here also now Metal seated butterfly valve is replacing Gate,Ball valve as it is easier to operate with low to zero maintenance cost and cheaper due to use to less metal in comparison to gate valve.
3. IBR Application :- We all know IBR valves are used is a very critical application for steam,Boiler ,Hot gases etc here valve has to perform in extreme high temperature & pressure conditions in rating from #150, #300 ,#600,#900 ,here gate valve is generally preferred to use , but now Triple Offset Butterfly valve which is also called quarter turn gate valve is used for the new projects and replacing the gate valve in older projects.
4. Control Valve :- Previously Globe ,ball valve was generally preferred to use in control valve application generally in fertilizer , Oil & gas sector but now metal seated butterfly valve with size selected on sizing calculation is considered to use in control valve even in critical application like – Hydrocarbons ,ammonia ,hot gas ext .( examples in Energy saving projects in IFFO -aonla,Phulpur ,Kalol – Triple offset Metal seated Butterfly valve with Pneumatic actuator and positioner is used to replace previously mounted ball valves in the Ammonia plant. ( Pls refer to Product capsule for 28”#300 – Control valve working since 2010 in Carin Bhogat terminal and refer the IFFCO kalol order of 18” #600 ).
5. Suitable for higher sizes & ratings, Critical application :- Metal seated Butterfly valve is easily used in higher temperature upto 900 Degree C ,Rating #1500 – 260 bar and sizes upto 100 “ , we have already received the order of 88” from IOCL Paradip for Hot gas application ( refer to product capsule), Dangote refinery ( PO attached with GAD) for flare gas application and IOCL Gujarat – 76” Refer the PO),Sour Service ,Cryogenic application,Hydrogen application etc.
6. Power sector – Ash line ,ACW ,DM Plant, Hydrogen cooler line here Triple Offset butterfly valve is now replacing Gate Valve in existing lines at Thermal Power plants in a large extent.
