vom Betriebsmedium durchströmt

12:33 Jul 4, 2017 

The not unessential "werden müssen" means "needs to be," which was indicated in L-man's Answer ("require"). The whole clause is written in the passive voice, as expected in a technical text. To convert properly to the active voice, one needs to do more than rearrange the subject and verb. When I said that the flow is active (bad word choice), I meant that an energy input is being suggested. The suggestion, perhaps the "nuance" that Björn referred to, may be lost when trying to convert to the active voice.

15:09 Jul 3, 2017 

that's why I suggested "passes", this is both active and passive.

14:57 Jul 3, 2017 

Hello, herbalchemist.
I agree with you that "is flowed through" is correct English, especially in this technical context.
My comment was to note firstly that the website cited was not so reliable, and secondly to indicate an alternative phrasing.
Regarding the alternative phrasing (with "flows" instead of "is flowed"), I suggested this would be more common, although I didn't have any statistics to back that up, and am open to be persuaded otherwise.
Nevertheless, prima facie there is some support for my comments. Compare
http://www.bing.com/search?q=+"fluid is flowed through ...
(1 hit for "is flowed")
versus
http://www.bing.com/search?q=+"fluid flows through the ...
(22 hits for "flows")
I accept that there is a subtle difference in the connotations: "flows" could suggest 'of its [the fluid's] own accord', while "is flowed" definitely suggests 'intentionally driven by some externally provided motivation'. Arguably "is flowed" would be a closer literal match for the original German text; however, it still would not be my first choice.
—David

14:41 Jul 3, 2017 

Hello, all.
As Björn Vrooman and Lancashireman have pointed out, "müssen" logically should be included in the translation because it was optional in the German text. The translation should reflect the intention of the original author.
I don't mind "have to", but I would more naturally tend to use "must" here (and in other technical contexts). In my experience this is not at all unusual.
For example, "must" and "must not" appear throughout
https://www.eduweb.vic.gov.au/edulibrary/public/ohs/Guidance...
"[...] Hazardous Substances must be stored in original containers [...]."
"If transferred to or kept in other containers, these must be compatible [...]."
"Containers [...], must be checked regularly." (comma is a bit odd here)
"[...] cabinets must be used to store chemicals [...]."
"Liquids must not be stored above powders and solids [...]."
In my opinion, "have to" would sound somewhat more casual/informal in the above sentences — like what I might say to someone (orally).
In a contract or similar formal document, occasionally you also see "shall", as in: "[...] Hazardous Substances shall be stored in original containers [...]."
—David

14:40 Jul 3, 2017 

"The motive fluid is flowed through the nozzle and into the mixing chamber" is perfectly good technical English. My point was about the perhaps odd-sounding "is flowed through," which occurs in many US patents. "The fluid flows through the nozzle... " has a different meaning.

14:20 Jul 3, 2017 

Hello, herbalchemist.
I wouldn't use abprogetti.com/liquid-ejectors.html as a reference for 'good' English. It has several odd/wrong expressions.
Example: "The Liquid ejector are Venturi jet device." This has odd/wrong capitalisation, and the subject and verb do not agree.
"The motive fluid flows through the nozzle and into the mixing chamber." would be more typical.
—DIV

10:10 Jul 3, 2017 

I hadn't read Gudurun's note on Harald's answer. "Flow/Is flown" follows English norms, maybe, but it isn't used this way. A common construct is (the fluid) "is flowed through". Example: The motive fluid is flowed through the nozzle and into the mixing chamber. abprogetti.com/liquid-ejectors.html

01:52 Jul 3, 2017 

"From which the medium (hydraulic fluid) must be flown through" indicates that an active mechanism, like pumping, is required. The Answer should be passive and the flow active if this is the correct interpretation.

15:48 Jul 2, 2017 

@Michael
"because that requirement or condition is logically implied"
-The same can be said about the German.

Like:
"welche ***vom Betriebsmedium durchströmt*** werden." Period.

This isn't about a simple description, IMO, but there's a certain nuance in here--some emphasis on this particular requirement, for whatever reason.

Best wishes to both of you and have a nice Sunday evening!

15:47 Jul 2, 2017 

@Edith
Dunno; it's not unheard of. E.g.
"Since air entering the inlet port must pass through this
opening before reaching the outlet port, this adjustment also
determines the rate of airflow through the restrictor."
https://www.faa.gov/regulations_policies/handbooks_manuals/a...

+

"For example, on standards published by IEC (International Electrotechnical Commission), ASTM (American Society for Testing and Materials), IEEE (Institute of Electrical and Electronics Engineers), requirements with 'shall' are the mandatory requirements, meaning 'must', or 'have to'. The IETF (Internet Engineering Task Force) defines shall and must as synonymous terms denoting absolute requirements, and should as denoting a somewhat flexible requirement, in Request for Comments (RFC) documents."
https://en.wikiversity.org/wiki/Technical_writing_specificat...

Don't get me wrong; of course, I'm OK with replacing "must" by "have/has to." Considering that "fluid" is the subject of the sentence, I just don't see the "guns to your head" if you know what I mean.

15:15 Jul 2, 2017 

that's why I left it out. And I'm a non-US variety and agree with your assessment. However, I'd never use must in a technical context, no guns to your head.

15:11 Jul 2, 2017 

Non-US varieties often seem to use 'must' when there's a degree of urgency, and yet, it's still your own decision. US speakers may not be as concerned about that particular nuance except perhaps in certain set phrases (e.g. "if you must"). I think neither one is needed here because that requirement or condition is logically implied.

14:34 Jul 2, 2017 

has to pass, I dislike must in such a context. But I agree with the rest.

13:46 Jul 2, 2017 

Why not rewrite the sentence? As Gudrun pointed out, the verb should be used in the active voice; I agree with Edith about "pass through" and with Michael about reversing the word order because the next sentence starts with component, so you should end the first one with it. And someone has yet to deal with "müssen."

E.g.:
In a hydraulic system, the working fluid must pass through several components. Each of them...