Finishing - March-April 2022
Who knew that after coming out of a pandemic, the world could get any worse, but how wrong was everybody. The effects of the war are going to be be huge for industry. Industry that was already under price pressure, but fuel costs now are going to be astronomical. I truly hope that your business survives this latest onslaught. Fair play to all those people volunteering to look after refugees. They have my undying respect and it shows the people of the UK to be a country full of sympathy and humanity. I hope this message is seen from the outside world as I fear that sometimes our leaders may distort how UK citizens really feel. Good luck in the coming months, I think we might need it.
Who knew that after coming out of a pandemic, the world could get any worse, but how wrong was everybody.
The effects of the war are going to be be huge for industry. Industry that was already under price pressure, but fuel costs now are going to be astronomical. I truly hope that your business survives this latest onslaught.
Fair play to all those people volunteering to look after refugees. They have my undying respect and it shows the people of the UK to be a country full of sympathy and humanity. I hope this message is seen from the outside world as I fear that sometimes our leaders may distort how UK citizens really feel.
Good luck in the coming months, I think we might need it.
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38 PUMPS<br />
Pump<br />
performance<br />
The thermodynamic method of<br />
monitoring pumps is based on the first<br />
law of thermodynamics i.e. the increase<br />
in the internal energy of a thermodynamic<br />
system is equal to the amount of heat energy<br />
added to the system, minus the work done by<br />
the system on its surroundings. In basic terms<br />
the energy losses in the pumping process<br />
result in a temperature rise in the fluid.<br />
The concept of centrifugal pumps is based<br />
on Bernoulli’s principle that there are three<br />
forms of energy in a fluid system – potential,<br />
kinetic and pressure. Kinetic energy and<br />
potential energy are the thermodynamic<br />
properties of the fluid system and the two<br />
energy quantities of heat and work are<br />
required to account for real world conditions.<br />
The thermodynamic method for pump<br />
testing requires the following data:<br />
temperatures of the pumped fluid at pump<br />
suction and pump discharge; suction and<br />
discharge pressure; motor input power and<br />
motor efficiency. To measure the energy losses<br />
dissipated as heat, corrections are applied for<br />
the specific heat and density of the pumped<br />
fluid.<br />
A test engineer uses the monitoring system<br />
to take readings from a fully open discharge<br />
valve until any fluctuations in temperature<br />
have settled out. The engineer will then<br />
continue to take readings for a predetermined<br />
amount of time at set points of<br />
the discharge valve until the valve is fully<br />
closed. This will then map the pump curve<br />
from the fully open to fully closed position of<br />
the discharge valve. The pump curve will then<br />
be compared to the original test curve of the<br />
pump and any losses in performance or<br />
increase in absorbed power will show signs of<br />
wear.<br />
As the running clearances open up<br />
between the wearing parts of the pump, the<br />
leak paths of the pumped fluid increase,<br />
resulting in lost efficiency. A thermodynamic<br />
monitoring system detects and records these<br />
losses more accurately than other test<br />
<strong>Finishing</strong> - <strong>March</strong>/<strong>April</strong> <strong>2022</strong>
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