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Ceramic Chipped UHMW - Need different material!

Ceramic Chipped UHMW - Need different material!

Ceramic Chipped UHMW - Need different material!

(OP)
I'm using a ceramic chipped filled UHMW for skids on my anyhdrous tool bar. I was told that they would outlast standard UHMW material in abrasion resistance, but after 500 acres in sandy/rocky soil, the skids are in need of replacement. I'm looking for a material that will outlast my current skid. The ideal material will be easily drilled/punched and have the ability to bend to the shape of the attach plate without stressing the skid. If at all possible, I need to be able to install this skid without heating it up to make it plyable. Dimensions are 1/4" thick, 4.5" wide, 19" long, with a large radius 45 degree bend in the middle. Any suggestions will help! Thank you!

RE: Ceramic Chipped UHMW - Need different material!

A lot depends on the mode of failure.

A list of good abrasion resistant materials follows, but their rankings change with speed, weight (pressure), and nature of opposing surface.

PE
UHMWPE
Xlinked PE
polyurethane (PU)
nylon (PA)
acetal (POM)
polyester (PET)
PTFE (Teflon)

Various fillers like graphite, MoS2, mineral (whatever that means), glass fibre, bronze, carbon fibre, aramid pulp (Kevlar), ceramic (whatever that means).

If it is melting and burnishing locally at the high load points, look for a material with a higher melting or softening temperature.

If it is cutting, look for a harder material.

Contrary to the above, sometimes the ability to bend a little to share the load before cutting can help. That seems to work in favour of PU.

Regards
Pat
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RE: Ceramic Chipped UHMW - Need different material!

(OP)
I believe the failure is caused by a cutting action, but it may be a combination with melting.  From past experience, the poly sometimes appears as if a torch was used to soften some of the edges. I run at no more than 15mph in the fields, but travelling over some of the sandy soil, I could see that the skid would tend to heat up a bit.

Assuming that it is a combination problem due to cutting and melting, what would you suggest as an alternative?

The link below is a picture of my setup so you can better see what I have going on. Thank you.

http://files.engineering.com/getfile.aspx?folder=0ed694ee-a933-42a5-90da-25827cccf912&file=High_Speed_NH3_-_side.JPG

 

RE: Ceramic Chipped UHMW - Need different material!

(OP)
Do you think a 1/2" nylon strip will have enough flexibility to make the required bend, yet not be stressed too much, causing a weak point?

RE: Ceramic Chipped UHMW - Need different material!

Unfilled extrusion grade nylon tends to have an elongation of over 100%, but the force required to bend it will be a lot higher than required for HDPE.

It will be easier if you heat it in an oven for a few hours. The required temp depends on the type of nylon. If it's 6.6 I think about 180 deg C should do it.

It probably will if you immerse it in water at about 60 deg C for about a week then boil it for a few hours.

 

Regards
Pat
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