Recent content by maxh

To answer your questions The tank is steel and the heaters are inserted sideways at the bottom of the tank as close to bottom dead center as the construction code permits for hillside nozzles of the diameter used. The tank is connected to a pumped main, pumped mains have valves, pumps and...

Sorry, am only a student of life these days Let me re-phrase the question. If I take two microphones, set them apart by a known distance and measure sound speed between them, using a single pulse from a speaker and measuring the time lag, will I get the same answer, if I then take those same...

The water is heated using immersion heaters and the tank is to be uninsulated. I know this means that we will have to work out heat input from the heaters and heat lost from the tank to the external environment - time for head in a book to refresh those calcs I have not done for a good few...

Hi Guys, An interesting question for you. Does the sound speed of air (or any other gas) contained in a pipe vary from what you would calculate in from the typical formula v = (k.g.R.T)^0.5 ? Where v = sonic velocity k = Cp/Cv R = Universal gas constant T = Absolute temp Would the size and...

Thanks for the advice quark What if the pipe were connected to a large reservoir whereby when the temperature falls, the volume reduces but the head on the tank remains the same as the reservoir only falls a fraction of not very much at all. I guess I would have to put air in to compensate for...

Hi Guys - methinks I have enabled you to get hold of the wrong end of the stick. If the air expands or contracts the water level in the tank will fall / rise as the tank is connected at the bottom to a pipeline which terminates in an open ended discharge some 90 metres above the level of the...

Thanks IRstuff but I am concerned about expansion / contraction of the air volume. Would the air above the water be at 10% humidity ? If the air is at 100% humidity does it still act like a perfect gas when heated / cooled or does the water vapour change its behaviour ? maxh

Dear sirs, I can't enter this interesting debate, but I have a question in this vein. Can anyone say if you get a different sound speed in a pipe than you would in free field conditions for a gas at the same conditions. Would the pipe dimensions with respect to frequency be important ?

Hi - can anyone help on this I have a water tank 10m o/heads by 2.6m diameter operating at 8 to 10 BarG. The water tank is situated outside, is uninsulated, and the water temperature is generally 5C throughout the year, to prevent freezing in winter extremes the tank has immersion heaters...

Would love to use a reducer SnTMan but we have some internals welded inside and we are scratching for every last mm of straight length. We are even having debates about few mm for this or that part, and this is essentially a fabricated product !! I will check the excess in the shell and...

Hi I am wondering how to consider an opening in a pipe manifold. I have a 12"NB pipe manifold that at the end terminates with a standard pipe cap. However, what I wish to do is cut a 6" i/dia hole centrally in the 12"NB pipe cap, then weld a 8"NB pipe onto the pipecap in such that the 6"...

Thanks guys Yes I do remember Benny Hill. Your help is appreciated. Max

Steve, We haven't been specified a site temperature, not a helpful client, so I guess we are left with the possibility that if we leave the tank exposed we might get a surface temperature of anything up to 150-200 Deg F (egg frying temperatures). I would think the air temperatures will quite...

To answer and clarify some of the points. Re: Instruments and attachments We are supposed to provide level and pressure gauges and spring loaded pressure relief valves. There will be some instrumentation cabling - I guess we can shade this from direct sunlight by careful design. Re: Duty The...

Dear all I have to provide some pressure vessels, containing unheated water at up to 20 BarG, for use in Saudi Arabia on a pumping station. The vessels are located outdoors and our client has suggested that we need to protect the vessels against the sun. Has anyone experience of these type of...