Passenger Trains > What if you added weight to F125/Charger?

Please pardon my ignorance; I'm clearly not that knowledgable.  But I'm struck by the apparent similarities between the new T4 Charger/F125 and the varieties of Eurosprinters.  What I mean -- and I know it's simplistic -- is that 4000+ HP (8600 in the Eurosprinter!) when it weighs 130K just means the wheels spin at excessive acceleration, right?  I know that's a complaint about the Chargers, but if traction caused by weight is an issue, what would happen if you added enough to get it to 175 or 200 K?  Isn't this something the US is going to have to wrap it's head around, in that engines are going to get more powerful than physics' ability to provide traction?  Thanks in advance.

According to the brochure, the F125 is 280K lbs.

chidino Wrote:
-------------------------------------------------------
> Please pardon my ignorance; I'm clearly not that
> knowledgable.  But I'm struck by the apparent
> similarities between the new T4 Charger/F125 and
> the varieties of Eurosprinters.  What I mean --
> and I know it's simplistic -- is that 4000+ HP
> (8600 in the Eurosprinter!) when it weighs 130K
> just means the wheels spin at excessive
> acceleration, right?  I know that's a complaint
> about the Chargers, but if traction caused by
> weight is an issue, what would happen if you added
> enough to get it to 175 or 200 K?  Isn't this
> something the US is going to have to wrap it's
> head around, in that engines are going to get more
> powerful than physics' ability to provide
> traction?  Thanks in advance.

Not sure where you are getting your information from, but the Charges weight in at about 265,000.

He may have meant 130 tons which would be around 265k instead of 130k.

chidino Wrote:
-------------------------------------------------------
>...when it weighs 130K
> just means the wheels spin at excessive
> acceleration, right?



No. Wheels spinning on rail is a bad thing and everything is done to prevent it.

If your wheels are spinning, you're lost tractive effort.

Same thing goes when decelerating.

chidino Wrote:
-------------------------------------------------------
> Please pardon my ignorance; I'm clearly not that
> knowledgable.  But I'm struck by the apparent
> similarities between the new T4 Charger/F125 and
> the varieties of Eurosprinters.  What I mean --
> and I know it's simplistic -- is that 4000+ HP
> (8600 in the Eurosprinter!) when it weighs 130K
> just means the wheels spin at excessive
> acceleration, right?  I know that's a complaint
> about the Chargers, but if traction caused by
> weight is an issue, what would happen if you added
> enough to get it to 175 or 200 K?  Isn't this
> something the US is going to have to wrap it's
> head around, in that engines are going to get more
> powerful than physics' ability to provide
> traction? 

With controlled creep, which was developed and patented by EMD on the 50 series locomotives back in the 1980s, the adhesion is dramatically increased with resultant increases in tractive effort. Thus, adding weight to the locomotive doesn't really accomplish much. Compare this to an NHRA  top fuel dragster or funny car, with something over 11,000 HP and with controlled slippage of those huge tires, they accelerate to 320+ MPH in under 4 seconds in 1000 feet! Controlling wheel speed & slippage, seriously increases adhesion levels.

Besides, adding unnecessary weight to the locomotive, increases axle loadings which most railroads attempt to keep under 70,000 pounds per axle, while 65,000 to 68,000 pounds per axle is best.


Thanks in advance.

Duna Wrote:
-------------------------------------------------------
> chidino Wrote:
> --------------------------------------------------
> -----
> >...when it weighs 130K
> > just means the wheels spin at excessive
> > acceleration, right?
>
>
>
> No. Wheels spinning on rail is a bad thing and
> everything is done to prevent it.

Apparently you haven't heard of the EMD "Super Series" wheel speed control system, developed back in the 1980s. Also, you must be unfamiliar with NHRA Nitro Fuel burning Top Fuel Dragsters and Funny Cars.


> If your wheels are spinning, you're lost tractive
> effort.

NOT if properly controlled.

> Same thing goes when decelerating.

Again, it depends.

HotWater Wrote:
-------------------------------------------------------
> Duna Wrote:
> --------------------------------------------------
> -----
> > chidino Wrote:
> >
> --------------------------------------------------
>
> > -----
> > >...when it weighs 130K
> > > just means the wheels spin at excessive
> > > acceleration, right?
> >
> >
> >
> > No. Wheels spinning on rail is a bad thing and
> > everything is done to prevent it.
>
> Apparently you haven't heard of the EMD "Super
> Series" wheel speed control system, developed back
> in the 1980s. Also, you must be unfamiliar with
> NHRA Nitro Fuel burning Top Fuel Dragsters and
> Funny Cars.
>
>
> > If your wheels are spinning, you're lost
> tractive
> > effort.
>
> NOT if properly controlled.
>
> > Same thing goes when decelerating.
>
> Again, it depends.



Yes, as an ex-RR operations officer I'm familiar with wheel slip control and spinning vs. controlled creep.

I made a quick post, you put it better. I agree with your post.

HotWater Wrote:
-------------------------------------------------------
> chidino Wrote:
> --------------------------------------------------
> -----
> > Please pardon my ignorance; I'm clearly not
> that
> > knowledgable.  But I'm struck by the apparent
> > similarities between the new T4 Charger/F125
> and
> > the varieties of Eurosprinters.  What I mean
> --
> > and I know it's simplistic -- is that 4000+ HP
> > (8600 in the Eurosprinter!) when it weighs 130K
> > just means the wheels spin at excessive
> > acceleration, right?  I know that's a
> complaint
> > about the Chargers, but if traction caused by
> > weight is an issue, what would happen if you
> added
> > enough to get it to 175 or 200 K?  Isn't this
> > something the US is going to have to wrap it's
> > head around, in that engines are going to get
> more
> > powerful than physics' ability to provide
> > traction? 
>
> With controlled creep, which was developed and
> patented by EMD on the 50 series locomotives back
> in the 1980s, the adhesion is dramatically
> increased with resultant increases in tractive
> effort. Thus, adding weight to the locomotive
> doesn't really accomplish much. Compare this to an
> NHRA  top fuel dragster or funny car, with
> something over 11,000 HP and with controlled
> slippage of those huge tires, they accelerate to
> 320+ MPH in under 4 seconds in 1000 feet!
> Controlling wheel speed & slippage, seriously
> increases adhesion levels.
>
> Besides, adding unnecessary weight to the
> locomotive, increases axle loadings which most
> railroads attempt to keep under 70,000 pounds per
> axle, while 65,000 to 68,000 pounds per axle is
> best.
>
>
> Thanks in advance.

Well someone better tell this to the bean counters at U.P. and CSX because they have adding weight to their freight motors for years just so they can pull more with better traction.

Posted from Android

The-late-EMD Wrote:

>
> Well someone better tell this to the bean counters
> at U.P. and CSX because they have adding weight to
> their freight motors for years just so they can
> pull more with better traction.
>
> Posted from Android



Passenger locos don't normally have a problem with starting a train, which is where additional weight on drivers is an advantage.

Serious question- why do railfans refer to accountants as "bean counters"- probably more than 90% of the time?  Makes railfans sound childish (see also "propeller head", etc)

Duna Wrote:
-------------------------------------------------------
> The-late-EMD Wrote:
>
> >
> > Well someone better tell this to the bean
> counters
> > at U.P. and CSX because they have adding weight
> to
> > their freight motors for years just so they can
> > pull more with better traction.
> >
> > Posted from Android
>
>
>
> Passenger locos don't normally have a problem with
> starting a train, which is where additional weight
> on drivers is an advantage.
>
> Serious question- why do railfans refer to
> accountants as "bean counters"- probably more than
> 90% of the time?  Makes railfans sound childish
> (see also "propeller head", etc)

I've heard the phrase "bean counters" elsewhere, but I do wonder the history behind the phrase.

Nathan

atsf121 Wrote:)
>
> I've heard the phrase "bean counters" elsewhere,
> but I do wonder the history behind the phrase.
>
> Nathan


https://www.phrases.org.uk/meanings/bean-counter.html

Duane Witte
Holt, MO

The-late-EMD Wrote:
-------------------------------------------------------

> Well someone better tell this to the bean counters
> at U.P. and CSX because they have adding weight to
> their freight motors for years just so they can
> pull more with better traction.

Please provide specifics, i.e. exactly what type of locomotives?

Duna Wrote:
-------------------------------------------------------
> Serious question- why do railfans refer to
> accountants as "bean counters"- probably more than
> 90% of the time?  Makes railfans sound childish
> (see also "propeller head", etc)

Have heard it used by railroaders, in the Air Force and by a fair number of people at AT&T.
 

The-late-EMD Wrote:
-------------------------------------------------------

> Well someone better tell this to the bean counters
> at U.P. and CSX because they have adding weight to
> their freight motors for years just so they can
> pull more with better traction.
>

Freight and passenger are two radically different services with different requirements.

TAW

Optimised wheelslip control increases tractive effort. Extra weight on driven axles increases tractive effort because it increases the power that can be used without causing wheelslip. So wheelslip control and weight are together the nost significant factors used to control wheelslip.

exhaustED Wrote:
-------------------------------------------------------
> Optimised wheelslip control increases tractive
> effort. Extra weight on driven axles increases
> tractive effort because it increases the power
> that can be used without causing wheelslip. So
> wheelslip control and weight are together the nost
> significant factors used to control wheelslip.

Well yes, unless one wishes to control wheel SPEED, i.e. controlled slip, by the use of comparing ground speed (with radar) to wheel speed. By properly controlling wheel speed, the adhesion level is markedly increased, without the use of sand (sand actually becomes a lubricant). Wheel slip control, i.e. the detection and subsequent correction (by reducing power) is the old method, used on diesels prior to the EMD 50 series. With "Super Series" wheel speed control, the wheels are allowed to slip, but wheel speed is controlled by the excitation control system, producing much higher level of adhesion & tractive effort. With AC traction motors, the concept is even more improved.

HotWater Wrote:
-------------------------------------------------------
> exhaustED Wrote:
> --------------------------------------------------
> -----
> > Optimised wheelslip control increases tractive
> > effort. Extra weight on driven axles increases
> > tractive effort because it increases the power
> > that can be used without causing wheelslip. So
> > wheelslip control and weight are together the
> nost
> > significant factors used to control wheelslip.
>
> Well yes, unless one wishes to control wheel
> SPEED, i.e. controlled slip, by the use of
> comparing ground speed (with radar) to wheel
> speed. By properly controlling wheel speed, the
> adhesion level is markedly increased, without the
> use of sand (sand actually becomes a lubricant).
> Wheel slip control, i.e. the detection and
> subsequent correction (by reducing power) is the
> old method, used on diesels prior to the EMD 50
> series. With "Super Series" wheel speed control,
> the wheels are allowed to slip, but wheel speed is
> controlled by the excitation control system,
> producing much higher level of adhesion & tractive
> effort. With AC traction motors, the concept is
> even more improved.

Controlling wheel speed is exactly what I was referring to by 'optimised wheelslip control'.

exhaustED Wrote:
-------------------------------------------------------
> HotWater Wrote:
> --------------------------------------------------
> -----
> > exhaustED Wrote:
> >
> --------------------------------------------------
>
> > -----
> > > Optimised wheelslip control increases
> tractive
> > > effort. Extra weight on driven axles
> increases
> > > tractive effort because it increases the
> power
> > > that can be used without causing wheelslip.
> So
> > > wheelslip control and weight are together the
> > nost
> > > significant factors used to control
> wheelslip.
> >
> > Well yes, unless one wishes to control wheel
> > SPEED, i.e. controlled slip, by the use of
> > comparing ground speed (with radar) to wheel
> > speed. By properly controlling wheel speed, the
> > adhesion level is markedly increased, without
> the
> > use of sand (sand actually becomes a
> lubricant).
> > Wheel slip control, i.e. the detection and
> > subsequent correction (by reducing power) is
> the
> > old method, used on diesels prior to the EMD 50
> > series. With "Super Series" wheel speed
> control,
> > the wheels are allowed to slip, but wheel speed
> is
> > controlled by the excitation control system,
> > producing much higher level of adhesion &
> tractive
> > effort. With AC traction motors, the concept is
> > even more improved.
>
> Controlling wheel speed is exactly what I was
> referring to by 'optimised wheelslip control'.

OK, but THAT is not what EMD, nor GE, calls their modern era wheel speed control system, at least I know EMD didn't, when "Super Series" was developed and patented. The term "wheelslip control" is the old "detection and correction" system, i.e. it is NOT continuous control. The wheels must loose adhesion, then that is detected, and THEN corrected. It was thus a "reactive" system.

I don't really care what companies call their proprietary systems - if you control wheelslip by some/any method then by definition that's wheelslip control.