positive displacement pump 2

[142846]

Hello everyone,
I have a question about positive displacement pump or compressor.
what does mean the word of positive in sentence of positive displacement pump/compressor. The word of positive really refers to what? what or which operation or action or ... is positive in positive displacement pumps/compressors. Is there any negative displacement compressor or pump?

 

[142846]

FACS, my exprience is more than 20 years in oil and gas industry and same as you i had not thought about that befor, until recently a talented student ask me (what is the role of "positive" word in "positive displacement pumps")? in the other hand what means positive in "positive displacement pumps".i have gotten some good respond from above members. But on your contrary i do not think it is waste of time, this is try to help a student. Any way I interest to see your answer. thank you.

 

[Compositepro]

TiCl4 has it right. Positive means certain or assured in this context. If this question did not occur to you as a student, it probably never will, but I'm surpised so many did not know. This use of the word positive is not all that uncommon, even today. I guess we engineers are so used to associating positive with negative in our work.

 

[electricpete]

Well,now that you mention English definitions of positive, here's the one that matches what many have described above:

https://www.merriam-webster.com/dictionary/positive

b(1): independent of changing circumstances : UNCONDITIONED

an insurance policy with positive coverage

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(2B)+(2B)' ?

 

[142846]

Compositepro,
I am not fluent in English, but i think all types of pumps are certain and assured in domain of their applications.

 

[hydtools]

Dararia, if that is true then there is no need for any type description for the device named pump.

Ted

 

[FACS]

I'm going to call it Linear Displacement Pump. Now and forever.

 

[SandCounter]

Compositepro, are you positive about that?

Dararia, you are positively obdurate. . . and I don't mean that in a negative sense.