Hi all, First time poster here and I'm stuck with what for me seems to be a simple problem. The situation is this: I have a 100mm diameter pipe connected to a steam kettle, which produces steam at a constant 0.3barG. This pipe is split up into 4 50mm pipes, each pipe has a valve at the end that can be opened and closed and an orifice downstream with a diameter of 37mm. The pressure after the valve is atmospheric (0 barG). The manufacturer has given me a figure of consumption of steam per hour, although I do not know under which conditions this number is calculated. The steam passing through has a temperature of 108C, which corresponds to the pressure. I want to calculate the velocity of the steam when its passing through the orifice (and the velocity when no orifice is applied). I know it has something to do with bernoulli's law and I tried using the calculators at TLV.com, however I seem to get contradictory answers. F.e. when I calculate the flow rate through the orifice and use that number to calculate the velocity through the pipe (flow rate is constant throughout the pipe?) I get results which would indicate that not using an orifice increases the velocity, which (of course?) is not true. Can anybody point me in the right direction? Thanks in advance!