About 15 years ago I met this D5H LGP in France . First I thought the track chain was beside the rollers , but I noticed a third track rail , outside the normal chain. The machine was used for reclamation work at an old lignite mine . It worked all day long on slopes (LGP is essential) but the conditions were hard (LGP is not the right thing) . In order to prevent bending of the wide tack shoes this system was used . Who knows the name of this sytem ? Is there anyone with experience ? I asked every specialist but nobody has ever seen it . Am I the only one ? The Netherlands , johan7
johan7; I remember seeing a D5H LGP about ten years ago, that is in Victoria Australia ??. but i see its only Half a chain i thought there was a whole chain each side on the machine i saw. Cheers Leroy
The high drive skidders have tracks like that. They also have longer track frames, more out the back for Ballancer when hauling logs. Later Bob
Here is a brochure on the 527 track skidder that shows the undercarriage in a little more detail - http://xml.catmms.com/servlet/ImageServlet?imageId=C645364
Very common on logging machines here in the Northwest. The Canadian loggers pioneered the use of this setup on excavator tracks for shovel loggers and processors built on excavator chassis.
A few details from the Cat website, hopefully this link will work: http://parts.cat.com/parts/undercarriage/tri-and-quad-link-tracks
Hello there , thanks to all of you in helping me find the name for my rare running gear : it is called TRI-LINK and even QUAD-LINK as I read in the brochures you put on the site . The Netherlands , johan7
It's a solution to prevent extremely wide track shoes bending in high impact application.s Must admit it was a new one on me, but then again in our applications we tend to go with the narrowest shoes we can find.
Yair . . . We once had a pair of D9g's identical except there was a stuff up and they were delivered one with twenty four inch as ordered and one with twenty seven inch tracks, the narrow tracked machine would drag the other backwards and there was no noticeable difference in flotation in the wet. It came up in passing talking to another Scrub Puller that final drives went longer with wider plates. Cheers.
They take a second set of chain, split them in half and mount them on either side. It keeps the chain from twisting too much in rough terrain. I believe loggers and such would called them "bitch links" lol.
I don't see flotation issues on our 9's & 10's with 24" shoes. Shoe bending becomes an issue if using wider shoes on hard underfoot conditions. Everything works fine unless the operator tries to do something stupid ...........
Yair . . . I guess the point I was trying to make was (contrary to some common belief) narrower tracks within reason apply more force and maybe put more stress on final drives which wear out sooner. I can see the logic in the finals lasting longer on a LGP tractor as they appear to be as useless as t**ts on a bull if you ask them to work on normal ground. It is truly amazing where they can go though and not get stuck. Cheers.
The Tri-links and Quad-links reduce the twisting force that make the links open up on the track pins and bushings when you use wide pads. Wide pads are specified in different places in the Northwest to reduce damage to the ground. It is usually a state regulation applied on state lands. I first saw the idiocy in state officials when they required wide pads on a skidder but it's OK to use the tallest and nastiest pads on a feller buncher. Run one of those on soft ground and it looks like Paul Bunyan drug his chain saw across the earth.
that system is called a quad rail track loggers use em because of the added support on the main rails
I am not a huge fan of a track press already. Could you imagine pressing 6 pins to change one link? I need a faster press!