Variable Orifice / Damper - experienced

[doad1]

Hello, I need to get tips for supplier of variable orifice located in the Stack of HRSG Boiler (fi=7000mm). The Stack is currently equiped with stack damper (NEM), in further Project,, Plant unit will be connected to the CO2 Capture Plant .To prevent air ingress to the CCC Plant Stack should be equipped with in "1st scenario - closed design" with additional flap but in "2nd scenario - open design" with variable orifice with hole approx. fi=6500mm. Orifice should be able to adjust position to reach the best anti-ingress flow according to phase of operation (Boiler & GT start-up, turning-down, CCC Plant shut down etc.). Could you advice me possible solution & manufacturer?

 

[rmw]

Dampers, louver, radial vane, guillotine, etc are variable orifices for duct-work and stacks (although Guillotines are best used as opened or closed for shut off purposes).

Tight shutoff is by guillotines or double louver with seal air between the blade sections.

Google any of the above words and the word 'damper' and you should be reading for a while.

Good luck.

rmw

 

[doad1]

rmw: Yes, you are 100% right, all of I know and I have experience,,,done. But , according to requirements of fail safe operation of GT (max. allowed backpressure, pressure fluctuation etc.) we need to keep design of Stack opened (any , shut off elements = additional pressre drop , slow response time etc,),,, CFD calculations been provided for various operation conditions to avoid overreaching air ingress and we need special design of "moving" orifice. We advanced and have idea of design and now we are trying to find experienced manufacturer. Nevermind. Thanks a lot.