Western Railroad Discussion > Undercutter at Work

Union Pacific had an undercutter at work on the Greeley Subdivision at milepost 13.75 Henderson, Colorado, March 27, 2017.  The Caterpillar 329D excavator with undercutter attachment cleared out dirt and ballast under the south switch.

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Great video.

(Equipment also useful in cutting down giant sequoia and redwood trees! 
/sar)


 

A Maintainer's PITA.

UP used Ballast Tools Equipment CBH 1108 Caterpillar 329D excavator with undercutter attachment at Henderson, Colorado, March 27, 2017.

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CZ,
Good catch. Have not seen one like that work. upkpfan

Chip - Very interesting video. Thanks for posting.

Paul Brennecke
Golden, CO

Are these in common use? I can see a few operator eyeball/skill kinda issues. The video makes it look kinda close to bottom of the ties.

SP4360 Wrote:
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> A Maintainer's PITA.

Yes, I strongly suspect so. I wish someone with time on this equipment would elaborate. Interesting video, thanks. d

Interesting video, thanks for posting.  I'm somewhat curious about the use of this machine.
I'm guessing it's for use at switches.  Mainline undercutters are track mounted, but I can
see where that would be a problem at a turnout, hence the need for this specialized 
machine.  And let me add this is the first time I've seen such an implement.  

Nick Tharalson,
Marion, IA

TCnR Wrote:
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> Are these in common use? I can see a few operator
> eyeball/skill kinda issues. The video makes it
> look kinda close to bottom of the ties.

Pretty common on the SF Transcon. I usually see a few of those attachments left at differ stations. There is a trackhoe that hyrails also and it will undercutter with those attachments.

Posted from Android

dpudave Wrote:
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> SP4360 Wrote:
> --------------------------------------------------
> -----
> > A Maintainer's PITA.
>
> Yes, I strongly suspect so. I wish someone with
> time on this equipment would elaborate.
> Interesting video, thanks. d

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The undercutter bar is either from Joy Global or Cinncinatti Mine Machinery
The undercutter chain is mos tlikey from Cinncinatti Mine Machinery.
The undercutter bar appears to be a fifteen foot length undercutter bar which would hold 33 feet of undercutter chain approximately.

Shame on them for not using water to flush the dirt and dust away from the undercutter bars chain channel.
if they used water the undercutter chain and bars would last much longer and cost less to maintain due to reduced wear as the water
flushes out the dirt and dust and fine gravels from the chain and undercutter bar.

The Undercutter bar is designed with replaceable wear parts which are: the undercutter chain guides, the nose piece that is either set up with a
second star wheel sprocket or simply a welded nose piece in two halves that is replaced as needed ,They use heated rivets to secure the replacement
straight chain guide pieces in place.

The undercutter chain has links that can be replaced individually with driven pins to secure the chain links in place using a tapered undercutter chain guide pin
to align the connector and undercutter bit links.
The under cutter chain comes in two types, conical bit chain or flat bit chain. Both types of bits use a carbide cutter.
The Undercutter chain and bar has a chain tensioner that has three parts and is located at the rear of the cutter bar in front of the star wheel
thses parts are the threaded tensioner rod the tensioner nut and the lock nut for the tensioner nut.

An undercutter bar and chain that is used to remove old ballast creates much less stress and pressure than when used underground in a room and pillar mining operation or when they are used on the following mining systems;
1. cable tensioned undercutters
2. self propelled undercutters mounted on tires or railcars.
3. self propelled drum miners with integral cutter chains that are part of the miners drum head.
4. long wall mining shearers. 

The star wheel which is a four tooth sprocket is under the mess of guards and steel plates
at the rear of the undercutter bar where the sprocket would be below that
This undercutter does not make use of a slip clutch system to protect the undercutter chain and the bar.
I am unable to determine if the hydraulic motor attached to the star wheel is a radial piston or axial piston motor




 



Edited 2 time(s). Last edit at 03/29/17 15:11 by leonz.

leonz Wrote:
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> The undercutter bar is either from Joy Global or
> Cinncinatti Mine Machinery

I don't know about any of that.  This machine is from Ballast Tools Equipment.

http://www.btequip.com/products/browse-by-equipment?task=getProduct&product-id=34

 

MP555 Wrote:
-------------------------------------------------------
> leonz Wrote:
> --------------------------------------------------
> -----
> > The undercutter bar is either from Joy Global
> or
> > Cinncinatti Mine Machinery
>
> I don't know about any of that.  This machine is
> from Ballast Tools Equipment.
>
> http://www.btequip.com/products/browse-by-equipmen
> t?task=getProduct&product-id=34
>
==============================================================================================================================>  
I was simply trying to explain how undercutters are used in mining and what it involves as well
as the two major suppliers of the undercutter bars and undercutter chain. It is no fun changing
the carbide conical bits or flat undercutter bits especially when they are broken off flush in the
under cutters bit holding chain link.

================================================================================================================================


 



Edited 1 time(s). Last edit at 03/30/17 12:23 by leonz.

Thanks lionz, d