Farringdon Elizabeth Line Station

Post by Roland Perry
Mainly about the eastern side (surface building 23 Long Lane, which is
consistent with the building next door being signed 18-19; a mystery why
http://perry.co.uk/images/Farringdon-East-External.jpg
The name over the doors(s) is Farringdon, and there are sliding doors
facing both Long Lane and the side-roads, although so far they only
appear to use the side-road opening. Note the duplicate "No Entry" and
Farringdon" signage facing Long Lane.
Down at platform level there are signs indicating which end of the
platform to use if wanting either Farringdon Tube/National Rail, or
Barbican (the complex, not the station).
Loading Image...

Link corrected so it works.

Post by Roland Perry
Starting afresh from EL platform level looking up (southeast), there are
two similar-length banks of escalators, with an 'Interchange' (aka
mezzanine) level. Each bank has an inclined lift on the left parallel
with the escalators.
The famous "secret lift" [G] is in a lobby off the left of the
Interchange Level, and here's the layout diagram inside the upper
http://www.perry.co.uk/images/Farringdon-East-LiftGuide.jpg
Aside: it's not obvious why the upper bank has an inclined lift, rather
than a vertical one with horizontal passages top and/or bottom. Like at
Kings Cross Northern Ticket Hall. Unless they wanted symmetry, or
there's something under the surface in the way (which is one suggestion
for needing the lower inclined lift).

It's definitely not for symmetry, because Liverpool Street Liverpool Street
has one of each.

Anna Noyd-Dryver

Recliner

2022-07-05 13:08:23 UTC

Link corrected so it works.

It's definitely not for symmetry, because Liverpool Street Liverpool Street
has one of each.

A vertical lift would have been bad on several counts:
- It would have passed through the CWL trackbed, reserved for use as future S7 sidings
- It would have involved a long, unnecessary corridor to traverse in the booking hall
- It would have increased the space taken by the surface booking office, thus reducing the commercial potential of the
site.

Anna Noyd-Dryver

2022-07-05 13:41:45 UTC

Link corrected so it works.

It's definitely not for symmetry, because Liverpool Street Liverpool Street
has one of each.

- It would have passed through the CWL trackbed, reserved for use as future S7 sidings
- It would have involved a long, unnecessary corridor to traverse in the booking hall
- It would have increased the space taken by the surface booking office,
thus reducing the commercial potential of the
site.

I was imagining one starting at the top of the escalators, in the vicinity
of the current sloping lift entrance, and ending with a long passage at the
mezzanine level.

Or perhaps as seen at Liverpool Street Moorgate, two shorter vertical
lifts, with a walkway between them alongside the escalator bank. The only
photo I have is this one from that walkway…
<https://twitter.com/annanoyddryver/status/1544315452750544898>

Anna Noyd-Dryver

Recliner

2022-07-05 14:04:57 UTC

Link corrected so it works.

It's definitely not for symmetry, because Liverpool Street Liverpool Street
has one of each.

I was imagining one starting at the top of the escalators, in the vicinity
of the current sloping lift entrance, and ending with a long passage at the
mezzanine level.

Yes, that would be possible, but would involve digging out a long access tunnel. So, more expensive, less convenient for
users. The nice thing with the actual arrangement is that people who could use either the lift or an escalator (eg,
someone with luggage) can make an instant decision without having to go and find the lift, and see if it's working.

Post by Anna Noyd-Dryver
Or perhaps as seen at Liverpool Street Moorgate, two shorter vertical
lifts, with a walkway between them alongside the escalator bank. The only
photo I have is this one from that walkway…
<https://twitter.com/annanoyddryver/status/1544315452750544898>

How would that be better than the inclined lift? It would be less convenient for the users, and probably cost more to
build.

One nice thing about inclined lifts is that they are interchangeable with escalators or even stairs. For example, the
first London inclined lift (at Greenford) was built, I think, in the space previously occupied by an escalator.

They're also said to be cheaper to operate than a vertical lift (only half the power is needed).

And they cover horizontal ground, which is very useful in some cases, such as the Liz Barbican entrance, where the
surface entrance needed to be displaced some horizontal distance from the platform ends.

Anna Noyd-Dryver

2022-07-06 19:09:43 UTC

Post by Recliner
One nice thing about inclined lifts is that they are interchangeable with
escalators or even stairs. For example, the
first London inclined lift (at Greenford) was built, I think, in the
space previously occupied by an escalator.

LU's last wooden escalator, indeed!

Post by Recliner
They're also said to be cheaper to operate than a vertical lift (only
half the power is needed).

I'm not sure how the physics is gonna work with that one! You're still
moving the same load [1] over the same height difference, just with a
sideways component too.

[1] the load being the difference between the weight of the lift cabin +
passengers/etc., and the weight of the counterbalance.

Anna Noyd-Dryver

Recliner

2022-07-06 19:30:34 UTC

LU's last wooden escalator, indeed!

Post by Recliner
They're also said to be cheaper to operate than a vertical lift (only
half the power is needed).

I'm not sure how the physics is gonna work with that one! You're still
moving the same load [1] over the same height difference, just with a
sideways component too.
[1] the load being the difference between the weight of the lift cabin +
passengers/etc., and the weight of the counterbalance.

The net weight being moved is the difference between the lift+pyaload and
the counter-weight (probably sized to be about the same as the lift plus
half the maximum payload). The motor must be powerful enough to move the
maximum value of that net load (ie, half the maximum payload).

The force required to move that net weight will be about half as much with
a 30° inclined lift as with a vertical lift, so it needs a motor with about
half the maximum power (ie, lower cost). The cables similarly need only
about half the strength rating, but they'll of course need to be about
twice as long.

So, the lower power motor will make more revolutions, so it uses about the
same energy, but costs less and is smaller. I think the emergency brake
will also be simpler (ie, cheaper) with an inclined lift.

Tweed

2022-07-06 20:07:19 UTC

LU's last wooden escalator, indeed!

Post by Recliner
They're also said to be cheaper to operate than a vertical lift (only
half the power is needed).

I'm not sure how the physics is gonna work with that one! You're still
moving the same load [1] over the same height difference, just with a
sideways component too.
[1] the load being the difference between the weight of the lift cabin +
passengers/etc., and the weight of the counterbalance.

The net weight being moved is the difference between the lift+pyaload and
the counter-weight (probably sized to be about the same as the lift plus
half the maximum payload). The motor must be powerful enough to move the
maximum value of that net load (ie, half the maximum payload).
The force required to move that net weight will be about half as much with
a 30° inclined lift as with a vertical lift, so it needs a motor with about
half the maximum power (ie, lower cost). The cables similarly need only
about half the strength rating, but they'll of course need to be about
twice as long.
So, the lower power motor will make more revolutions, so it uses about the
same energy, but costs less and is smaller. I think the emergency brake
will also be simpler (ie, cheaper) with an inclined lift.

I don’t buy your motor argument. All you effectively are doing is using the
inclined plane as a reduction gear, which of course you could do with the
vertical lift.

Recliner

2022-07-06 20:43:44 UTC

Post by Tweed

LU's last wooden escalator, indeed!

Post by Recliner
They're also said to be cheaper to operate than a vertical lift (only
half the power is needed).

I'm not sure how the physics is gonna work with that one! You're still
moving the same load [1] over the same height difference, just with a
sideways component too.
[1] the load being the difference between the weight of the lift cabin +
passengers/etc., and the weight of the counterbalance.

The net weight being moved is the difference between the lift+pyaload and
the counter-weight (probably sized to be about the same as the lift plus
half the maximum payload). The motor must be powerful enough to move the
maximum value of that net load (ie, half the maximum payload).
The force required to move that net weight will be about half as much with
a 30° inclined lift as with a vertical lift, so it needs a motor with about
half the maximum power (ie, lower cost). The cables similarly need only
about half the strength rating, but they'll of course need to be about
twice as long.
So, the lower power motor will make more revolutions, so it uses about the
same energy, but costs less and is smaller. I think the emergency brake
will also be simpler (ie, cheaper) with an inclined lift.

I don’t buy your motor argument. All you effectively are doing is using the
inclined plane as a reduction gear, which of course you could do with the
vertical lift.

That's the benefit that's normally cited for these lifts. I suppose you
could say that it avoids the cost and maintenance of a reduction gearbox or
a higher powered motor, as well the more sturdy mountings needed to cope
with the higher lifting forces required with a vertical lift.

Tweed

2022-07-06 20:51:13 UTC

LU's last wooden escalator, indeed!

Post by Recliner
They're also said to be cheaper to operate than a vertical lift (only
half the power is needed).

I'm not sure how the physics is gonna work with that one! You're still
moving the same load [1] over the same height difference, just with a
sideways component too.
[1] the load being the difference between the weight of the lift cabin +
passengers/etc., and the weight of the counterbalance.

The net weight being moved is the difference between the lift+pyaload and
the counter-weight (probably sized to be about the same as the lift plus
half the maximum payload). The motor must be powerful enough to move the
maximum value of that net load (ie, half the maximum payload).
The force required to move that net weight will be about half as much with
a 30° inclined lift as with a vertical lift, so it needs a motor with about
half the maximum power (ie, lower cost). The cables similarly need only
about half the strength rating, but they'll of course need to be about
twice as long.
So, the lower power motor will make more revolutions, so it uses about the
same energy, but costs less and is smaller. I think the emergency brake
will also be simpler (ie, cheaper) with an inclined lift.

I don’t buy your motor argument. All you effectively are doing is using the
inclined plane as a reduction gear, which of course you could do with the
vertical lift.

I think you cracked it earlier on - they are installed where more spacially
advantageous, ie they fit in better.

Recliner

2022-07-06 21:10:27 UTC

LU's last wooden escalator, indeed!

Post by Recliner
They're also said to be cheaper to operate than a vertical lift (only
half the power is needed).

I'm not sure how the physics is gonna work with that one! You're still
moving the same load [1] over the same height difference, just with a
sideways component too.
[1] the load being the difference between the weight of the lift cabin +
passengers/etc., and the weight of the counterbalance.

The net weight being moved is the difference between the lift+pyaload and
the counter-weight (probably sized to be about the same as the lift plus
half the maximum payload). The motor must be powerful enough to move the
maximum value of that net load (ie, half the maximum payload).
The force required to move that net weight will be about half as much with
a 30° inclined lift as with a vertical lift, so it needs a motor with about
half the maximum power (ie, lower cost). The cables similarly need only
about half the strength rating, but they'll of course need to be about
twice as long.
So, the lower power motor will make more revolutions, so it uses about the
same energy, but costs less and is smaller. I think the emergency brake
will also be simpler (ie, cheaper) with an inclined lift.

I don’t buy your motor argument. All you effectively are doing is using the
inclined plane as a reduction gear, which of course you could do with the
vertical lift.

I think you cracked it earlier on - they are installed where more spacially
advantageous, ie they fit in better.

Yes, that's definitely the main reason for installing them. Also, I doubt
that a single underground inclined lift would be installed in isolation.
They make most sense as one of a bank of escalators and staircases.

Roland Perry

2022-07-07 06:36:52 UTC

LU's last wooden escalator, indeed!

Post by Recliner
They're also said to be cheaper to operate than a vertical lift (only
half the power is needed).

I'm not sure how the physics is gonna work with that one! You're still
moving the same load [1] over the same height difference, just with a
sideways component too.
[1] the load being the difference between the weight of the lift cabin +
passengers/etc., and the weight of the counterbalance.

The net weight being moved is the difference between the lift+pyaload and
the counter-weight (probably sized to be about the same as the lift plus
half the maximum payload).

That wouldn't be a good choice, because I think the inclined lifts at
Farringdon said 17 people, and even without social distancing I doubt
you'd normally get more than four people sharing one. The average
loading is probably more like two.

Post by Recliner
The motor must be powerful enough to move the maximum value of that net
load (ie, half the maximum payload).

Even a very small motor could shift the load, if sufficiently low
geared. What you actually mean is the power required to accelerate the
load swiftly to the cruising-speed, after which less power is required
to maintain that speed.

Post by Recliner
The force required to move that net weight will be about half as much with
a 30° inclined lift as with a vertical lift, so it needs a motor with about
half the maximum power (ie, lower cost). The cables similarly need only
about half the strength rating, but they'll of course need to be about
twice as long.
So, the lower power motor will make more revolutions,

That entirely depends on the gearing between the motor shaft and the
pulley wheel, most obviously incarnated in the diameter of the pulley
wheel.

Post by Recliner
so it uses about the same energy, but costs less and is smaller.

Given that the energy required is equivalent to the increase potential
energy of the load (minus frictional ad braking losses) it doesn't
matter what the 'slope' of the lift is, because you are raising the same
number of kg the same number of metres.

--
Roland Perry

Bob

2022-07-07 07:06:06 UTC

LU's last wooden escalator, indeed!

Post by Recliner
They're also said to be cheaper to operate than a vertical lift (only
half the power is needed).

I'm not sure how the physics is gonna work with that one! You're still
moving the same load [1] over the same height difference, just with a
sideways component too.
[1] the load being the difference between the weight of the lift cabin +
passengers/etc., and the weight of the counterbalance.

The net weight being moved is the difference between the lift+pyaload and
the counter-weight (probably sized to be about the same as the lift plus
half the maximum payload). The motor must be powerful enough to move the
maximum value of that net load (ie, half the maximum payload).
The force required to move that net weight will be about half as much with
a 30° inclined lift as with a vertical lift, so it needs a motor with about
half the maximum power (ie, lower cost). The cables similarly need only
about half the strength rating, but they'll of course need to be about
twice as long.
So, the lower power motor will make more revolutions, so it uses about the
same energy, but costs less and is smaller. I think the emergency brake
will also be simpler (ie, cheaper) with an inclined lift.

The change in potential energy is weight times vertical height moved.
Anna is correct that the total energy required is the same for a
vertical lift as for an inclined one.

In an inclined lift part of the weight is supported on the "track", so
Recliner is correct that the tension in the cable is less.

For a given vertical distance, an inclined lift needs to move further
in its direction of travel. Assuming negligible friction, the
reduction in cable tension, by trigonometry, is exactly cancelled by
the longer distance travelled, so the energy transfered is the same.
In reality the inclinded lift will likely have more frictional losses
than a vertical one, as more bearign surfaces are involved.

The power rating of the motor will depend on the journey time required.
Power is force * velocity (dot product, but in this case the vectors
are aligned). If the two lifts are to complete their journey in the
same time, the inclined lift will need to move faster, so lower force
but higher velocity, so the power would need to be the same.

Robin

Recliner

2022-07-07 07:11:46 UTC

Post by Bob

LU's last wooden escalator, indeed!

Post by Recliner
They're also said to be cheaper to operate than a vertical lift (only
half the power is needed).

I'm not sure how the physics is gonna work with that one! You're still
moving the same load [1] over the same height difference, just with a
sideways component too.
[1] the load being the difference between the weight of the lift cabin +
passengers/etc., and the weight of the counterbalance.

The net weight being moved is the difference between the lift+pyaload and
the counter-weight (probably sized to be about the same as the lift plus
half the maximum payload). The motor must be powerful enough to move the
maximum value of that net load (ie, half the maximum payload).
The force required to move that net weight will be about half as much with
a 30° inclined lift as with a vertical lift, so it needs a motor with about
half the maximum power (ie, lower cost). The cables similarly need only
about half the strength rating, but they'll of course need to be about
twice as long.
So, the lower power motor will make more revolutions, so it uses about the
same energy, but costs less and is smaller. I think the emergency brake
will also be simpler (ie, cheaper) with an inclined lift.

The change in potential energy is weight times vertical height moved.
Anna is correct that the total energy required is the same for a
vertical lift as for an inclined one.
In an inclined lift part of the weight is supported on the "track", so
Recliner is correct that the tension in the cable is less.
For a given vertical distance, an inclined lift needs to move further
in its direction of travel. Assuming negligible friction, the
reduction in cable tension, by trigonometry, is exactly cancelled by
the longer distance travelled, so the energy transfered is the same.
In reality the inclinded lift will likely have more frictional losses
than a vertical one, as more bearign surfaces are involved.
The power rating of the motor will depend on the journey time required.
Power is force * velocity (dot product, but in this case the vectors
are aligned). If the two lifts are to complete their journey in the
same time, the inclined lift will need to move faster, so lower force
but higher velocity, so the power would need to be the same.

I have the impression that the vertical speed of inclined lifts is usually
significantly slower than vertical lifts. Basically, they move at
approximately the speed of the adjacent escalator.

Roland Perry

2022-07-07 08:22:38 UTC