Talk:Injector

message: The ' eductor-jet pump' link just sends you back to this page. What the cabbage?  — Preceding unsigned comment added by 69.171.96.6 (talk) 15:12, 28 January 2013 (UTC)
thread_title: A Link To The Past

message: Moved to article.  --Dore chakravarty 05:04, 5 December 2005 (UTC)
thread_title: Move

message: In the second paragraph the word "atmosphere" links to a disambiguation page, what does it mean in this context? Bergsten 21:28, 6 December 2005 (UTC)
replies: text: The said word refers to Earth's atmosphere please.  --Dore chakravarty 22:37, 6 December 2005 (UTC)
replies: text:  Thanks! Bergsten 22:38, 6 December 2005 (UTC)
thread_title: atmosphere link?

message: Do you think this article would benefit from more stuff on downstream equipment from these ejectors?
Not sure if this to much information for an article such as this.
These systems are notoriously difficult to operate and design. However, these issues probably do not apply in all areas of ejector appplication.
Toothtools (talk) 21:38, 27 June 2008 (UTC)
thread_title: More info for downstream equipment

message: The photo of the Nathan 4000 Non-lifting injector at the top of this article is pretty useless. It's unclear what part of the photo is actually an injector. Has anybody got a better one? --Roly (talk) 19:01, 28 November 2014 (UTC)
replies: text: In the absence of any comment, I have replaced the image as suggested. --Roly (talk) 17:43, 1 April 2015 (UTC)
thread_title:  Nathan 4000 Non-lifting injector  

message: Before immediately just jumping into how they work, it would be good 
to explain the point of the device.  *Why* are they used? e.g. instead 
of other types of pump?  What is the result that's being sought? 
The description says 
"...creates a low pressure zone that draws in and entrains a suction fluid. 
After passing through the throat of the injector, the mixed fluid expands 
and the velocity is reduced which results in recompressing..."
Which sort of hints that the purpose of the device is also for "mixing" 
fluids, but it sounds like it went through low pressure, and then 
"recompressed"... why "do and undo"?  what is the end result?  What 
has changed?  Is the mixed fluid then also diffused (with some of the 
remaining added kinetic energy, perhaps to keep it mixed with even more 
air to not recondense?)  Please explain. 
There is too much "what's going on" and not enough "what's the point" in the introduction. 
Is it "just a pump", or is it something more? (There's not much about "Injectors"
in the general article on "pump"s.) 
(The "Modern uses" section is just a list, but it doesn't explain how this 
device manages to satisfy these particular needs any differently/better than
some other choice of pump... it just somehow does.) 
When should one consider using an injector in a design for something that needs
a pump? 
104.5.72.176 (talk) 16:09, 26 July 2015 (UTC)
replies: text: I think we might revisit the issue now and see what editors who now watch the talk page think. Without re-engaging with the contentious issue of page merges, we could rewrite this page - as the IP notes, the lead is hopeless (in particular, you could be forgiven for thinking the injectors on steam locomotives just get water up to the clack valve and something else shoves it through) - starting with the Giffard injector and the significant fact that you can get water into a boiler using steam at lower pressure than the boiler itself. I would be strongly in favour of such a rewrite. Pinkbeast (talk) 15:59, 28 July 2015 (UTC)
replies: text:  I think this should be re-split. Injector, Ejector, Feedwater injector or Boiler feedwater injector (it's not just steam locos) and even Ejector (vacuum brake) for steam loco brakes. Andy Dingley (talk) 16:14, 28 July 2015 (UTC)
replies: text: There's an argument for that too, but it wouldn't hurt to rewrite it - the words would still be useful after the split and the split would be more contentious. Pinkbeast (talk) 16:39, 28 July 2015 (UTC)
replies: text: This doesn't seem to have gone anywhere. If I get the time I'll chase up my copy of OUP "How steam locomotives really work" and rewrite the unsplit page. I would not argue with a split, I'm just too lazy to do it. Pinkbeast (talk) 19:04, 13 August 2015 (UTC)
thread_title:  better Introduction 

message: Recent edits removed:
"The addition of heat to the flow of water lessens the effect of the injected water in cooling the water in the boiler compared to the case of cold water injected via a mechanical feed pump."
describing this as redundant, and the following comparison to a feed pump was dismissed with "no need to compare to a pump". I do not feel it is remotely redundant; feed pumps were (as is discussed in the article) widely used on locomotives before the invention of the injector and the injector's superiority to them (thermal efficiency, limited number of moving parts, and ease of adjustment of the water input) is entirely germane to this article. I invite comments from other editors. Pinkbeast (talk) 23:16, 31 October 2016 (UTC)
replies: text: Comparison with feed pump certainly needed from a loco point of view, but I would have my doubts about restoring the sentence removed, which surely only applies when using exhaust steam (I'm only an ex-chemical engineer and therefore too much thinking makes my brain hurt, but if the injector is not running on exhaust steam where has the heat added to the feed water come from, other than from the water in the boiler?). From a chemical engineering point of view, a comparison between ejectors and pumps should be of interest, but would read significantly differently ('no moving parts' means you can use any number of corrosion-resistant materials you would struggle to make a reliable pump from). Generally I think the page does need to separate out the railways stuff from the chemical engineering stuff; the points to be made about one application are different from the points to be made about the other.Rjccumbria (talk) 00:32, 6 November 2016 (UTC)
replies: text: You're quite right if the injector is run on steam direct from the boiler (a "live steam" injector), but of course that is avoided where possible. Two injectors are normally provided (and two mechanisms of some sort for refilling the boiler _must_ be provided) and at least one will normally run on exhaust steam. Since ordinarily water consumption and making exhaust steam go hand in hand, it's usually possible to refill the boiler using an exhaust steam injector. Pinkbeast (talk) 01:44, 7 November 2016 (UTC)
replies: text: Ok, I follow; but the proviso about using exhaust steam could do with being explicit. And the more I look at the article the more I feel it needs taking in hand. As I think a previous WP-ian has pointed out on the talk page, an injector requires the motive fluid to be a condensible vapour; hence the last sentence of the 'Operation' section is spot-on for ejectors (and captures one of their principal advantages) but utter tish (and, indeed, tosh) for injectors. Rjccumbria (talk) 19:25, 7 November 2016 (UTC)
thread_title:  Recent reverts 

message: It would be very could if this article had more information on the theory of injectors and (easily applicable) formulas for dimensioning (theoretical formulas, and practical "cookbook" formulas taking various non-ideal inefficiencies into account). It may be good to divide this into four different regimes (in fact the articles should be generalized linking to or treating the steam injector a special case), gas-gas, gas-liquid, liquid-gas and liquid-liquid injectors (steam being gas of course).150.227.15.253 (talk) 11:19, 28 January 2019 (UTC)
thread_title:  Desired improvement: the general injector and the theory of it 

message: I found this article hard to understand and confusing.  Now I know why.  The article was the result of a merger that was never cleaned up.  Without explaining how a simple jet pump works, the article starts with something much more complicated, and the simple version only comes later.  The water injector for a steam engine is a very specialized jet pump, and the article should tell how it builds upon a simple jet pump.   Comfr (talk) 18:50, 25 October 2020 (UTC)
thread_title: Hard to understand

message: A discussion is taking place to address the redirect :Eductor-jet pump. The discussion will occur at Wikipedia:Redirects for discussion/Log/2021 March 31#Eductor-jet pump until a consensus is reached, and readers of this page are welcome to contribute to the discussion.  Cnilep (talk) 06:44, 31 March 2021 (UTC)
thread_title:  "Eductor-jet pump" listed at [[Wikipedia:Redirects for discussion|Redirects for discussion]]