Chain Stretch

[jokers]

Hi Frank,

Good points to consider, and thanks for adding to my knowledge of dozer tracks, this may come in handy some day.

I`m still believing that total elongation is wear and stretch although do admit that I`ve handled chains that had a perceptible shuck if you tried to first tension them, then compress them, which would lead me to believe that the significant part of that chain elongation is due to wear. Also when I consider the lessened initial bearing surface often found in holes which have been punched through metal, I can see where you would have rapid wear. The term escapes me right now, but you`ve no doubt seen the rough surface left as some of the metal is recessed from from the leading edges as metal is sheared or punched.

You`re winning me over Frank, especially after pointing out that a total .005 per drive link on a 72 driver chain will cause enough slack to be able to remove a tooth. A fundamental point indeed. You should feel lucky that I work very far downwind of you(inside joke not fit for public dissemination or the ears of federal regulators ).

I`ll still be attempting to deconstruct a stretched chain when I get a chance and I`ll let you know what I see.

Russ

 

[glens]

I'd have gotten in on this but I was too busy driving to Pennsyltucky, having one of the great times of my life, driving back, and getting caught up.

I can't hardly believe the ammount of quibbling without me!  Are you guys trying to show me I'm not needed around here?

Glen

 

[geofore]

no lube on tracks

On dozer tracks, to add lubricant like an oiler adds on a chain saw would be detrimental to the pins/bushings. When you scale up to that size and that slow a spin the lubricant would attract and hold dirt and grit causing extremely fast wear on the pins/bushings. A red herring if you're going down that road. Better to ask at what temperature does your chainsaw lube spontaneously ignite? A trick you might use in the field when welding wear hardening steel to dozer teeth is to drip a drop of 30 or 40 weight oil on the weld if the oil ignites it's 439F degrees, too hot to make the next pass and have a reliable weld. You wait until the oil does not ignite, just smokes, to make the next pass. This tells me that unless the lube on your chain is spontaneously igniniting your not up to temperature to stretch straps. The wear is most likely at the rivets/holes (elongation to oval) as they rub past one another at their weakest spot. You will also notice that the tie straps are dimpled to add strength just as steel corrugated when used to cover building or line mine shafts. That little bend in the metal is to add strength and reduce stretch. The elongation should be at the holes for the rivets. Every time the drive link hits a sprocket it rocks the links against the rivets. It rocks coming around the crank and again around the tip of the bar, as your chain speed goes up wear goes up exponentially.