I just took an Atlas Copco hammer class and found out some stuff I had never heard before, maybe this is common knowledge, but not to me. 1. If a hammer is greased improperly and grease gets between the piston and the tool, the impact can actually inject the grease into the metal! 2. If a standard hammer is used in water, the piston can act as a pump and draw water past seals and into the machines hydraulic system! 3. Without proper grease, the tool is passing by the bushing so fast that that it is spot welding! I guess technically this is what all metal transfer is, I just hadn't thought of it that way. 4. Lastly he just gave a really good explanation of why hammers should be stored vertically. If you leave them on their sides all the seals have to support heavy internal pieces like the piston. O-rings and backing rings aren't meant to be load bearing. Any way it was a really helpful class, I wish I had taken it before I built 5 or 6 hammers
Its ALWAYS FUN to learn new sh*t.. even if you don't use it.. you can just store the info away & baffle somebody w/ bullsh*t if ya need to.. I went to an injection pump class AT THE FACTORY, ABUNCH of x.. & when asking the instructor WHY this does this or WHY it does that.. the standard answer was>> "its a hydraulic phenomenon.. nobody knows".. No kidding.. THAT was the answer I got!!! I cant begin to tell you how many times I've used THAT ONE..!!! LOL..
Always ask why and you will find out how smart they really are. It is easy to get men to understand information, procedures and long words, but it's difficult for them to understand reasons.
Oh yeah, I've definitely had a (Detroit) teacher with a set agenda who was annoyed by any question you had that kept him from ticking off all his talking points and finishing the day. Then I've had a (Cummins) Teacher who would stop the class and search through data until he had a clear answer. It's as if tech teachers vary as much as service manuals.
Some of that is new to me. Interesting. I know of a poor feller that bought himself a rental hammer that was basically scrap due to using the wrong grease....
One other thing they didn't tell you. Hammers should be greased with weight on the moil(chisel). If it's greased lying down a blob of grease will sit between the moil and piston then when it's used the grease will pass the piston seal and enter the hydraulic system causing pump failure.
Will take note of those info
That's interesting stuff. Did they say anything about prying with the bit? Seems like everyone always talks about how bad that is but I've never understood why. I admit I don't know the first thing about breakers though.
"Prying with the Bit" ... I know of someone on a Kobelco exc that did that ... Broke the chisel !! about 3 inches in diameter. Metal has to be pretty hard to withstand the rock ... was very expensive to replace.
Ouch!, no this guy didn't mention it
Prying is bad for the internals holding the tool in place and may cause internal damage or a broken chisel/point . However.... it is made to be durable. There is a line between prying and pushing. Moving debris with the point is fine. Trying to snap a piece off instead of doing some more hammering to loosen it is bad. I think of breakers like a knife blade. You can cut and do what the intended use is all day long, but if you use it as a screw driver, it's going to break if you put too much force behind it.
Prying also wears out lower bushing...and allows for the top of the chisel to become out of alignment when firing. A hammer is just a big cylinder like in a motor. The piston is forced with pressure striking the top of your chisel...producing the impact. Not greasing & prying wears out the bottom bushing can create a misalignment when the piston strikes the chisel. You can crack your piston that way...which is insanely expensive due to it having to be hardened & then ground post hardening to get the tolerances. Costly to produce, not easily done by just anyone...big $$$. High temp grease is your friend. If you see ‘motor oil’ running down your bit...you’ve got the wrong grease. Don’t pry or dry fire (fire without chisel resistance) grease on the carrier, grease early & often. If you do a lot of hammer work get a lube station. They can be hooked up to grease every time it fires...and to shut off the aux hydraulics if the unit is empty.
do lube systems keep up now I know 10 15 years a go we tried it and they couldn't put out enough grease I didn't know if they had gotten that much better
We used Linclon systmens and they were great...that was 2004-2010 when I worked for the dealer. Even set them up to not run when they got empty.
Hammers are a ficke tool. I run the same hammer on two different diggers a Cat and a Doosan both require different front head and back head pressures to peck away all day. A good hammer tech will save you time and money and see that mountain turn to dust in no time. Temps are important too as nitrogen is fairly thermal stable but if you want longevity out of the tool tweeking it gets you there. I agree with all though the moil isnt a prybar and ive dragged the odd operational expert out of the cab and sent them to the gate for repeatedly stressing the tool in this way. " If you dont see results after a couple of hits ,you probably hitting it in the wrong spot!"
Good info. I guess keeping the hammer vertical standing is like a common sense? This will allow the breaker’s weight to push the tool and piston up inside the breaker. Here is a maintenance guide and checking list for keeping hammers, maybe mostly already known by you, just a supplement. maintenance guide
That's your first post? Welcome! Yeah the vertical thing made sense to me when I realized that the whole series of Orings and Back-up rings would end up with the piston just sitting on one point of the ring once the oil drains away. Like a lot rules though, it's probably hard to do in the real world. How many companies are really building a hammer stand to hold the tool when it's off a machine?
My two small hammers live laid down on the trailer cause we carry them everywhere My 2 bigger hammers we made a hammer stand for cause they dont get used all the time
Yeah... I guess right. Mostly they are put vertically when not using or displaying for long whiles. For many users, being convenient tends to be the first thing.
Never thought about laying hammer down when not using, but keeping it standing is definitely inconvenient for sure. Dangerous as well unless stored outside. We rebuilt our top 35 hammer for around 1700. Tire center refilled the nitrogen. Great tools, but very expensive! I have heard about keeping pressure on chisel.
Just a few thoughts, worked for a Tramac (Montabert) dealer back in the 90's. Replaced a lot of nose bushings and moil points due to prying and scabbling (not keeping pressure on the point) The other important thing to remember is to not only have the flow to spec, the back pressure (return) is just as important (most of the time,the lower the better). A broken point can be repaired, a trainer from Montabert in France taught us the procedure. Only worth it for 6" and larger points. I would guess I have welded up about 50 points, only had a couple of them fail. If anybody is interested I can dig thru my old notebooks and post it here Hope this helps
Sure, thankyou!
Always good to know how to do random things. I don't use a 6" breaker, but I'm sure the process is similar to welding 1" plate.
OK, here goes. didn't find my notes but kinda remember the process. You start by making a jig that rotates to hold the 2 pieces straight and tight. Most of the time they break at an angle, use a torch to chamfer the ends leaving a 3/4' flat end in the center (a little larger than a nickle). Now this is the lmportant point, you have to find a nickle.... a real nickle, (not the alloy kind they pass off now) and put it in between the flat end of the chamfer, and jig it tight. Preheat and maintain the point to about 100C+-, I used 7018 1/8" rod and welded it up. Use stringers ONLY (no weaves). Peen each layer. Alternate the passes lengthwise down the point (that's why the jig needs to rotate) until you are done. postheat for about an hour, remove from the jig, then place the point in a sand pile for about a day (very long cool down) NEVER use a grinder on the point, I only used a torch until the last couple I did. Used an Air Arc with a flat rod, seemed to work pretty good. I believe the nickle is used so that the point can be flexible enough to be pounded day in day out, and still have a hard surface. Too hard it is brittle, too soft, it bends. Well, that's my trip down memory lane, hope this helps.