Author Topic: The filthy five and St valentines sump info?  (Read 4677 times)

Offline benshannon

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The filthy five and St valentines sump info?
« on: August 10, 2020, 10:51:44 am »
So I have recently learned of this place after stumbling into it. I have read old reports of the syphon blocking, is it still operational? What state are the ropes and metal work like in the pitches? Is it worth the 1.5 hour wait for the sump to drain?

Online Benfool

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Re: The filthy five and St valentines sump info?
« Reply #1 on: August 10, 2020, 11:07:15 am »
I tried to use the siphon system at St valentines about 5 years ago and couldn't get it to work - we also tried bailing it which also didn't work as the drain hole was blocked. So I gave up.

I'm also unsure of the state of the ropes on the Filthy 5 at the minute - the last I heard they were in a really bad state. I'd certainly be careful going up them from the East Canal without first getting some more up to date information.

B

Offline benshannon

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Re: The filthy five and St valentines sump info?
« Reply #2 on: August 10, 2020, 05:24:12 pm »
Thanks mate. Yeah doesn't sound too promising

Online danthecavingman

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Re: The filthy five and St valentines sump info?
« Reply #3 on: August 10, 2020, 05:55:57 pm »
IIRC the bailing hole is blocked with the bailing bucket? Someone on here will remember better than me?

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Offline benshannon

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Re: The filthy five and St valentines sump info?
« Reply #4 on: August 12, 2020, 09:00:24 am »
It would be a shame if all that work just gets left derilict. Sounded like a brill trip

Offline SamT

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Re: The filthy five and St valentines sump info?
« Reply #5 on: August 13, 2020, 10:12:28 am »
Hi - Been my pet project for a long while (if you search back on the treads here - you'll see) .

Forget the drain, its been blocked for decades, and not just by a bailing bucket. Probably just years of small stones and sediment.

Got the siphon up and running about 10 (probably 15)  years ago - but its quite convoluted in its set up.   It basically takes too long to drain with those small hoses.  There were two running in parallel and it took about half an hour to drain.
The intake needs to be down in the deepest bit of the sump - which is at the little crouching sized bell, right where it sumps properly.

It all needs scaling up with bigger bore pipe (all in one section with no joints to avoid blockages).  I have a half built pump in my garage that was going to sit down in the deep bit, for priming the syphon an I intended to use 40mm blue mdpe water pipe.

The old rubber fire house needs stripping out of the place as its an eyesore, and if someone wants to return to me, the red bilge pump, I'd be grateful.

Please leave the dive line well alone.  Its the only way, currently, of pulling any new pipe through the sump. (though you need to remember to attached another line to it so that you retrieve it back through the sump once finished).

Once the siphon is up and running, the filthy five pitched could be re-bolted with P bolts and with either pull through rings, or left perma rigged.

Could be tempted out of retirement to get it finished off once and for all.

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Re: The filthy five and St valentines sump info?
« Reply #6 on: August 13, 2020, 11:52:34 am »

Could be tempted out of retirement to get it finished off once and for all.

I just spat coffee all over my monitor... :lol:

Offline A_Northerner

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Re: The filthy five and St valentines sump info?
« Reply #7 on: August 13, 2020, 11:59:30 am »
The old rubber fire house needs stripping out of the place as its an eyesore, and if someone wants to return to me, the red bilge pump, I'd be grateful.

So you're saying if I pulled all that stuff out for you you'd consider heading down there and sorting it out?
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Offline SamT

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Re: The filthy five and St valentines sump info?
« Reply #8 on: August 13, 2020, 04:52:05 pm »
 ;D ;)

Offline owd git

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Re: The filthy five and St valentines sump info?
« Reply #9 on: August 13, 2020, 05:18:09 pm »
zomjon and i need an excuse to be there more often i'm presumptuous  enough to to say. Soz Jon :thumbsup:
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Offline SamT

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Re: The filthy five and St valentines sump info?
« Reply #10 on: August 13, 2020, 05:23:34 pm »
Looks like I need to get that pump finished!!

Offline benshannon

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Re: The filthy five and St valentines sump info?
« Reply #11 on: August 13, 2020, 10:05:26 pm »
Oooooo this is exciting 😁😁😁😁

Offline chunky

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Re: The filthy five and St valentines sump info?
« Reply #12 on: August 13, 2020, 10:23:18 pm »
I went up the first couple of pitches from East canal a few years back till I saw what I had been going up and beat a hasty retreat! Always fancied the loop ever since I first read of it.

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Offline benshannon

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Re: The filthy five and St valentines sump info?
« Reply #13 on: August 14, 2020, 09:17:21 pm »
I've got a couple of friends that would also Be well up. For. Helping out this project 😁

Offline benshannon

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Re: The filthy five and St valentines sump info?
« Reply #14 on: August 15, 2020, 10:31:05 pm »
Talking to my friends we think we can donate rope to redo the pitches 😁

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Re: The filthy five and St valentines sump info?
« Reply #15 on: August 15, 2020, 11:43:22 pm »
Sounds like the retirement home will have a spare armchair soon then ;)

Offline Pitlamp

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Re: The filthy five and St valentines sump info?
« Reply #16 on: August 16, 2020, 09:25:53 am »
The easy way to sort this might be to persuade a member of the Cave Diving Group Derbyshire Section to nip through the short sump on a single tank and replace the rope down the pitches.

This information may be of use to anyone who accepts the contract:


Offline Rob

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Re: The filthy five and St valentines sump info?
« Reply #17 on: August 16, 2020, 04:03:49 pm »
I went up the first couple of pitches from East canal a few years back till I saw what I had been going up and beat a hasty retreat! Always fancied the loop ever since I first read of it.

I went up the F5 last year and never noticed any poor ropes/anchors, well nothing to raise serious concern. Probably mostly cos i didn't look and everything (including my eyes) was covered in mud!
The end is where we start....

Offline tdobson

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Re: The filthy five and St valentines sump info?
« Reply #18 on: September 24, 2020, 10:36:28 pm »
I was down there today, and noticed a coil of goodish looking rope by the sump. A gift from well wishers?

Am I right in thinking that removing the pipe from the cave and the bilge pump to return to SamT would be welcome?

 Could be a nice little project. I'd be really keen for a working way to drain it, and I'm happy to do my bit.

Offline SamT

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Re: The filthy five and St valentines sump info?
« Reply #19 on: September 25, 2020, 12:28:53 am »
I've been working on a better solution, its quite simple really, same as before, which worked, but was too faffy and slow. with two parallel pipes running, it took about 30mins to drain. The faff involved removing the pump from one pipe, to attach it to the other, and prime that one too.  Pipes were too small, which meant an gravel 'hoovered' up could cause a blockage in the pipe, which is what I expect has happened.

Just needs bigger bore pipe, and a bigger pump.

Nearly finished the pump, which has been sat in my garage in bits for years.  Been working on it a bit just recently.  Based on 6" soil pipe, with two flap valves.
Then we need a 50m coil of 40mm black mdpe pipe, which I dont mind putting my hand in my pocket for.

Pump sits in the sump, permanently, at the deepest bit just before it sumps proper. 40mm pipe runs through the sump and down the FF. All things being equal, pump should be big enough to get the syphon started, and at 40mm bore, once running, it should drain pretty darn fast.

Hopefully, just needs one volunteer, preferably the smallest member of the group to get wet and crawl into the sump, a few strokes of the pump to get it going, then crawl out and wait.

I'll let you know when the pump is finished.  Will put a concerted effort in this weekend to get it finished.
Then we'll buy the pipe, and game on.  Old pipe and small pump need dragging out. (though perhaps a stash on the FF side of the sump might be useful for emergencies). New pipe will need hauling though the sump  . Last time, we had two teams, one team either side, and the pipe got dragged through the sump using the dive line that is in there to pull it though from the FF side. Worked at treat and we had another line tied too, so we could retrieve the dive line back through the sump.

Yes, I'd appreciate it if the Red handled pump made its way back to me. But no biggie.

I've been recovering from a torn tendon in my knee, which is starting to get there now, but somehow a trip down giants still feels like it might be a bit much for it just yet.


Offline benshannon

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Re: The filthy five and St valentines sump info?
« Reply #20 on: September 25, 2020, 07:52:46 am »
Awesome, as I said before, we have some ropes to donate to the pitches 😁 hope your knee feels better soon

Offline tdobson

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Re: The filthy five and St valentines sump info?
« Reply #21 on: September 25, 2020, 08:10:44 pm »
Old pipe and small pump need dragging out. (though perhaps a stash on the FF side of the sump might be useful for emergencies).

Yes, I'd appreciate it if the Red handled pump made its way back to me. But no biggie.   

Let's see what we can do!

I've been recovering from a torn tendon in my knee, which is starting to get there now, but somehow a trip down giants still feels like it might be a bit much for it just yet.

Take it easy for now and focus on the topside engineering part - and we'll try and get the more logisticsy bits moving. Hopefully.


Awesome, as I said before, we have some ropes to donate to the pitches 😁 hope your knee feels better soon

Ben: do you and Ryan fancy a trip with me down to SVP to try and take this pipe apart, and bring this bilge pump back?

Happy to show you the round trip in reverse on the way back. :)

We may have met last December when Ryan took me and your media sec etc to Winnats head!

Offline benshannon

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Re: The filthy five and St valentines sump info?
« Reply #22 on: September 25, 2020, 08:37:56 pm »
I'm keen and I've asked Ryan.
Stupid question though. How many trips in giants is safe? I've done 2 recently so I'm aware of the radon issues. Or am I being paranoid?

Offline tdobson

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Re: The filthy five and St valentines sump info?
« Reply #23 on: September 26, 2020, 12:41:00 pm »
I'm keen and I've asked Ryan.

Fancy a trip on Monday afternoon? Leaving around 3:30pm? 

I realise it's an antisocial time, but I'm headed down anyway with two others.

If not - suggest a better day/time and let's do it!

Offline benshannon

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Re: The filthy five and St valentines sump info?
« Reply #24 on: September 26, 2020, 03:12:30 pm »
Sadly I'll still be at work mate, but I'll check my rota on Monday and find out my shifts and get back to you 😁

Offline tdobson

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Re: The filthy five and St valentines sump info?
« Reply #25 on: September 27, 2020, 12:03:09 am »
Sadly I'll still be at work mate, but I'll check my rota on Monday and find out my shifts and get back to you 😁

No stress. I'll try and get a good sense of what kit is needed and what we'll need to remove the pump etc. I have a fair amount of flexibility, including during the day - so if ever your shifts allow a daytime trip - feel free to suggest it.

Offline tdobson

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Re: The filthy five and St valentines sump info?
« Reply #26 on: October 01, 2020, 12:02:05 pm »
So the Caving Crew + Anna headed down to St Valentines Sump on Monday and started work.
Really, we were on a jolly to East Canal, but we swung by SVS to figure out what needed to be done.

We:

  • chopped the hose off the bilge pump
  • worked out what's needed to remove the rest
  • we removed the short length of pipe from the upstream side of the bilge pump
  • took photos of what's down there for reference
  • we were serious and solemn at all times as you'd all hope.

SamT: Shall we leave the long length of hose for the other side, or would it be best to bring it out?
Ben: any thoughts when you're up for another trip?

Here's a trip report from someone else's perspective: https://overgroundvunderground.blogspot.com/2020/09/giants-hole-east-canal.html

Offline benshannon

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Re: The filthy five and St valentines sump info?
« Reply #27 on: October 01, 2020, 05:54:41 pm »
Good work dude. I'll check my diary and bank balance and work it out. Struggling for fuel Money this month

Offline Mrs Trellis

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Re: The filthy five and St valentines sump info?
« Reply #28 on: October 01, 2020, 05:58:42 pm »
Sounds like a great trip. Were you all glowing afterwards?
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Offline SamT

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Re: The filthy five and St valentines sump info?
« Reply #29 on: October 01, 2020, 09:12:02 pm »
Nice one!

I'd leave a long length (or two)  for the far side of the sump.

And maybe a couple of decent big buckets.

My imagined scenario goes something like:

Team drain St vals and descend FF.  Spend ages faffing about in the east canal, or there's a big flood, or encounter some sort of epic.
Cant return up the main stream, thus re-ascend FF only to discover St Vals is full again and thus are trapped on the wrong side if it with no means of getting back out.

So spare flexible pipe can be primed relatively easily from that side, and a syphon set going down FF to drain the sump again, assisted with some relatively straight forward bailing.



Offline tdobson

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Re: The filthy five and St valentines sump info?
« Reply #30 on: October 02, 2020, 02:37:29 am »
I'd leave a long length (or two)  for the far side of the sump.

And maybe a couple of decent big buckets.

This all sounds great!

So currently the only thing on my work list is:
* take a screwdriver and remove the bilge pump, ready for its onwards journey home

I've not set the date for my next trip, but is there anything else we do that will be helpful later?

Are there other materials that will need carrying down there which we can sort out getting down there?
If the pipe was procured - we could work on getting that into position.

Sounds like a great trip. Were you all glowing afterwards?

One described it as "in my top 3 trips, ever". Tbf, it probably was in mine too - though I'm not prone to making a bit song and dance about it. Definitely my fav trip this year.

Good work dude. I'll check my diary and bank balance and work it out. Struggling for fuel Money this month

The struggle is real! I feel for you - I definitely can relate there  :doubt:
I probably can't help, but if I manage to summon my newbie-ish (yet becoming less newbie and has car + money!) caving friend from notts to come on a Giants trip - I'll give you a shout in case you can work out something.  :)

Offline tdobson

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Re: The filthy five and St valentines sump info?
« Reply #31 on: October 13, 2020, 12:40:51 am »
Intending to head down later today.

Not sure if I'll make it to SVS (it may, or may not, be quite a gentle trip), but in case I do, I'll take a screwdriver and grab the bilge pump.

Offline SamT

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Re: The filthy five and St valentines sump info?
« Reply #32 on: October 13, 2020, 10:22:01 am »
 :thumbsup:

Offline SamT

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Re: The filthy five and St valentines sump info?
« Reply #33 on: October 13, 2020, 10:47:26 am »
new pump nearing completion - just need to cut a couple of discs out of stainless for the "plunger" and glue it all together.

My main concern is how its going to sit in the sump, I think we may have to strap it to the wall, but that shouldn't too hard to achieve once the sumps drained and we can work without being waist deep in water!

Offline tdobson

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Re: The filthy five and St valentines sump info?
« Reply #34 on: October 13, 2020, 12:49:08 pm »
new pump nearing completion - just need to cut a couple of discs out of stainless for the "plunger" and glue it all together.

My main concern is how its going to sit in the sump, I think we may have to strap it to the wall, but that shouldn't too hard to achieve once the sumps drained and we can work without being waist deep in water!

Yep - once it's easily drainable, it should be relatively straightforward to mount it up like that.

Offline tdobson

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Re: The filthy five and St valentines sump info?
« Reply #35 on: October 14, 2020, 01:24:27 am »
Not sure if I'll make it to SVS (it may, or may not, be quite a gentle trip), but in case I do, I'll take a screwdriver and grab the bilge pump.

It would have gone, but we did a trip to Boss Aven instead. I'll get down there before long for the bilge pump.

Offline tdobson

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Re: The filthy five and St valentines sump info?
« Reply #36 on: November 02, 2020, 01:42:48 am »
Moist trip to Far Curtain + Standard Round Trip yesterday and we found 10 mins to recover the Bilge Pump to the surface. It's currently sitting in my van seeking a home.

Sam: if you want to PM me your address, I'll drop off the pump in a covid secure, lockdown compliant way sometime soonish-ish.

Offline SamT

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Re: The filthy five and St valentines sump info?
« Reply #37 on: November 02, 2020, 09:54:59 am »
Hi, Brill.  I'll PM you.

It just so happens that I finished building the new pump at the weekend. (What else to do on a wet weekend).

Just needs Eavis to get that 50m of black 40mm mdpe ordered and we're in business.

(hopefully! - need to test the pump really before it gets dragged down there.)



Offline SamT

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Re: The filthy five and St valentines sump info?
« Reply #38 on: November 02, 2020, 09:56:15 am »
Pics!

Offline SamT

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Re: The filthy five and St valentines sump info?
« Reply #39 on: November 02, 2020, 09:58:46 am »
more pics

Offline tdobson

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Re: The filthy five and St valentines sump info?
« Reply #40 on: November 02, 2020, 10:03:35 am »
Looks awesome! Great job ;D

Do we have a shorter length of 50mm mbpe to hand so we can test it?

Offline SamT

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Re: The filthy five and St valentines sump info?
« Reply #41 on: November 02, 2020, 10:11:25 am »
Needs to be 40mm as that is the size of the connector.  I was just going to cut a couple of meters of the 50m roll, as and when it arrives, then take it to a river somewhere.  I reckon if it can push up to a meters head, then we're fine, as I'm confident that the height of the lip on the far side is less than that.  I'm hoping it'll only take a couple of strokes on the pump to get the syphon started.  Once it does start, it'll not take too long to drain. (I'm guessing about 10 to 15 mins).

My one concern is that I've made the stroke length too long and there might not be enough room in the deep bit of the sump to fully extend the pump.  We'll see.

Offline tdobson

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Re: The filthy five and St valentines sump info?
« Reply #42 on: November 02, 2020, 12:42:03 pm »
"I'm not an engineer but" - is silt getting sucked into it likely to be an issue or worth trying to protect against in some way?

Offline SamT

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Re: The filthy five and St valentines sump info?
« Reply #43 on: November 02, 2020, 03:30:17 pm »
Its kind of why it needs a big diameter pipe - so that pebbles etc dont get stuck.  Those holes are about 10mm across on the inlet, so nothing bigger than 10mm should get it, which in turn shouldn't get stuck in the 40mm pipe.  I guess a little sediment may fall out of the water and settle in the pipe - when its all static. But hopefully not enough to block it, and it should get flushed through easily enough when the syphon is running.

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Re: The filthy five and St valentines sump info?
« Reply #44 on: November 02, 2020, 03:52:43 pm »

Just needs Eavis to get that 50m of black 40mm mdpe ordered and we're in business.


What length pipe do you need, Ive possibly got some in the lock up, will check later.

Offline SamT

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Re: The filthy five and St valentines sump info?
« Reply #45 on: November 02, 2020, 04:49:04 pm »
Eyup Mark.  about 30m I reckon.

I've fitted the pump together now with a 40mm (o.d.) connector.  (I could swap it out, but it'd be a faff to pull the pump apart).

Rob has just ordered some today so its not desperate, unless you do happen to have some lying about.

ta

Offline tdobson

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Re: The filthy five and St valentines sump info?
« Reply #46 on: March 31, 2021, 12:58:42 am »
Hey Sam,

Is there anything I can do to help get this project moving again? Presumably we have various awkward things we need to get to SVS?

Eager to help,

-Tim

Offline Cantclimbtom

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Re: The filthy five and St valentines sump info?
« Reply #47 on: March 31, 2021, 12:18:07 pm »
being really nosy on someone else's thread (so tell me to clear off as necessary) but a "trick" I've seen that worked well with syphons and fresh water, is making the last bit a wider bore pipe. Suppose you have 40mm pipe then you have the last bit as water exits a metre of 50mm plastic waste pipe. The ideal coupling between the two would be a smooth gradual change in diameter (30 degree cone) just as water enters the wider pipe, but a sudden step using a coupling can also work. (Some diy skills with plastic 50mm waste and 40mm waste pipe needed if you want gradual/smooth flow). As the water flows it expands into the larger diameter creating suction. You don't get energy from nowhere and if you get anything out of this this depends on if you have enough flow speed on diameter-change, but in some cases a metre of oversize on exit can noticeably help a syphon. Dunno if relevant in your case as I don't know the flow speeds/head etc, so make of my waffle what you want.
Enjoy...
Expert in incompetent tomfoolery

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Re: The filthy five and St valentines sump info?
« Reply #48 on: March 31, 2021, 03:02:35 pm »
So without getting too much into the physics here, which are probably esoteric, but is the idea that the 'tensile strength' of the water (assuming it's not exceeded) is sufficient to 'pull' more water through than would otherwise be possible by 'pushing' with gravity/atmos pressure alone? Or just that the greater volume ahead reduces the pressure required at the input end?

Offline SamT

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Re: The filthy five and St valentines sump info?
« Reply #49 on: March 31, 2021, 03:33:16 pm »

I think this will explain the reasoning.

https://en.wikipedia.org/wiki/Draft_tube#:~:text=Draft%20Tube%20is%20a%20diverging,the%20expense%20of%20its%20velocity.

increased pressure at the suction end.  less velocity at the exit, but I don't think any more or less water is shifted.

Offline Cantclimbtom

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Re: The filthy five and St valentines sump info?
« Reply #50 on: March 31, 2021, 07:07:06 pm »
Personally I'd have described it as the exact opposite of a rocket nozzle.
Trading energy that could be jet washing the bottom pool of your syphon in favour of a bit more suction in the pipe.

Edit: or for you mining types, look carefully at how the air exits the guibal labelled fig 6, it gets wider as it leaves to create suction

https://www.aditnow.co.uk/Photo/Guibal-Fan_43490/
« Last Edit: March 31, 2021, 07:27:13 pm by Cantclimbtom »
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Offline SamT

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Re: The filthy five and St valentines sump info?
« Reply #51 on: March 31, 2021, 08:52:20 pm »
Errr - that wasn't a rocket nozzle??  its a draft tube for a hydro turbine.

At the end of the day, extra suction at the intake still doesn't lead to an increase in the amount of water shifted, since it just slows the rate at the other then  :shrug:

 

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