Hi for school i have to do a project on lockout tagout of changing a cutting edge on a dozer, i was wondering if anyone has an pictures of doing this or any tips, thanks
Sorry, I don't think I have any pics handy, but depending on when your project is due, I could probably get some. The basic procedure at the mines (D10 and D11 size)is: 1. Position dozer on solid ground (shop preferred, but it does also get done in the pit) 2. Raise blade 4 or 5 feet and place certified stand (or good quality blocking) under the pusharms on both sides 3. Shut off master switch and apply lock and tag. 4. Since the edges are usually worn to the frog, the nuts need to be cut off with a torch. Use proper PPE and keep non-essential personnel away in case the nut/bolt pops. 5. If edges are to be flipped, weld pad eyes on each edge. 6. The new edges need the paint stripped off the back (either with a grinder or gasket stripper) or else they won't hold the torque and will fall off. Also weld eyes on the new ones. 7. Replace or flip edges 8. Install new nuts, washers and bolts 9. To do it properly, the nut should be tightened with a Hy-Torc, but most guys here just rattle them up with a 1" impact. 10. Remove lock/tag, raise blade and remove stands 11. Send dozer to workand clean up the area.
Most people I see do it the way (cut nuts off back ) BigDiesel said But It is easier than you think to cut heads off ,without damaging the cutting edge - - you do need to use a good size tip, but it is A LOT LeSS PAINFUL and quicker once you have done a few Also a lot safer than laying under blade , even when properly blocked things can happen.
Safety website Go to safety.cat.com for this and many related topics.
Thanks!! Its not due till may 10th so if you could get some pictures before then that you be great!!Thanks again
Here are a few pics of a D11R getting it's edges flipped in the shop. Sorry I don't have more, but my camera battery died, and also I didn't stick around the mine long enough to get any later pics. The stand is about 4' high. You can see the wear on the nuts on the back side. I understand the one comment about cutting the bolt heads off instead of the nuts underneath, but not many people would take the time to clean out all the holes. As long as both pusharms are blocked, it is safe to be under there. You gotta go under to torque them up anyways... Hope this helps
Lifting cutting edges Here is a handy tool for lifting cutting edges & cornertips. It is a minesite approved lifting device with a SWL of 250Kg (550lb) and used by inserting through hole on or close to balance point and the back piece slid down to lock the hook into the bolt hole. Once a shackle or hook passes through the pair of lifting eyes, it cannot disengage from the cutting edge. Used for removing and installing the edges on our Cat D11dozers. It is available to suit different bolt hole sizes but I do not know the manufacturer of this tool. If I can find out, I will post it here later. This tool saves having to weld lifting eyes onto the edges. Looks like procedures are much the same around the world at minesites for changing cutting edges. John
BigDiesels, they sure got all the use out of those edges didnt they?!!
You Think or you KNOW "I understand the one comment about cutting the bolt heads off instead of the nuts underneath, but not many people would take the time to clean out all the holes. As long as both pusharms are blocked, it is safe to be under there. You gotta go under to torque them up anyways..." It does take a brief learning curve - But is Quicker and easier once you master it - and blades dropping are not the only safety issue - itis easy to get burns from molten metal even with the proper safety gear- the shape of bottom of the blade makes a pocket so the metal wants to blow back A lot of the leather protector sleeves have a short slit to accommodate big hands - cut off enough of them and one will get ya Also unfortunately not every one puts washers under the nuts- which means you either get closer to your work or risk nicking moboard Just a few observations I have made in the last fifty yrs.
When cutting of cutting edge bolts underneath, I used to use a curved gouging tip on the oxy torch to cut each side off the nut then knock the bolt out. These tips do less damage as there is less oxygen force to penertrate into the blade material. It is only when working in hard rock that the bolts get damaged. In softer material, a good impact wrench will normally wind the nuts off. An oxy-acetelyne gouging tip is shown below. John
First off..I do not condone this thread. Second, you're in flipping school.....do the work yourself, failbot.
dang.....owned by an old thread