Flow thru' orifice, Q gpm = 25 x A x k x sq.root h
A = Cross sect area in2
k = 0.6 for water
h = differential head, Feet
Convert to Metric if required.
Use the gauge pressure instead of the pump curve, too many variables not allowed in curve, pipe losses ,filter restriction, worn pump etc...
To prevent air accumulation in the system pipelines ,fit an automatic air vent at the highest system point. As previously mentioned the system can be maintained full and pressured by the use of a jockey pump set to cut-in/out by a pressure switch arrangement.
Offshore Engineering&Design
A quick easy and flexible solution is to use a type of spray painting pistol. These have a suction line to fit in a barrel or boat well and the motive power can be air or a tap off from a seawater supply.
Offshore Engineering&Design
There are Marine Regulations regarding the size of sea chests and protection of sea mammals into the sea chest. The recommended sizing is to achieve a suction flow of 0.5 M/s,( approx. 1.5 ft/sec) which prevents the ingress of aforementioned mammals. This simple calculation will give you the...
A pressure surge is caused by an empty pipeline with air in it. The air is compressed as the water begins to flow and creates destructive water hammer effects. Fit a jockey pump ((Low power ,low flow) to maintain a full pipeline and possibly a little circulation line or safety valve to create a...
A pre -filter of diatomaceous earth/sand , will greatly extend the working life of your membranes and reduce the neccesity of cleaning.
Ensure a back flush arrangement is installed on the pre-filter, to facilitate its cleaning without the time-consuming job of dismantling.
Offshore...
A ratchet and pawl assembly would maintain the tension and prevent slipping of the motor.It would not be difficult to retro fit. This is similar to the freewheel arrangement on a bicycle wheel rear hub or an anchor winch brake.
Offshore Engineering&Design
Check your exhaust pyrometers, by swapping over from other cylinderss, as a first step. Also swap over or change fuel injectors.Check your turbo discharge air pressure and temperature is normal. Check the back pressure in your exhaust trunking.
Offshore Engineering&Design
It would greatly assist if the application of the bearing was known. I have seen bearing failures on Generator bearings due to electric tracking to earth via a bearing. This is difficult to detect and a proper earthing system is required.
Another failure .already mentioned is caused by welding...
Check the pump has a thrust bearing and is bearing against a shoulder on its shaft.Sounds like the pump shaft is floating, so giving variable pressures.
The thrust bearing should be positioned to take the back thrust of the impeller while allowing heat expansion along the shaft.
Offshore...
Check the rotation direction of your oil pumps and motor amps as a preliminary, before the obvious suction and discharge strainers and possible jammed relief valves
Offshore Engineering&Design
Have a look at this Hydra-ram, using gravity water power to lift your water, no other power needed.
http://www.allspeeds.co.uk/hydraulic-ram-pump/
Offshore Engineering&Design
i have experienced this problem. Root cause was casting sand which had congealed and remained in the piston internally. Worked loose and cause grinding effect on liner , eventually seizing piston on TDC and separating at gudgeon pin area.
Offshore Engineering&Design
