Repair BROKEN Cast Iron Cylinder Gland | Flame Spray Welding
how you going guys Kurtis from Cutting
Edge engineering so this is our first job for 2023 what we have here is a pair of d10
Blade tilt cylinders that have come in for repair what these cylinders are used for is
for tilting the blade left to right on the bulldozer as you can see the right hand cylinder
has been cut to pieces in order to disassemble it so there was a massive failure that went
on in there and the customer cut the head flange off the barrel so they could then retrieve
the piston and the gland there's also a lot of damage on the head gland and also on the
piston and the reason this generally happens there are two valves in the piston which allows
oil to bypass when the cylinder reaches its maximum stroke once the cylinder hits a stroke
it pushes that little valve out of the way and allows oil to bypass but quite often that
little valve will break loose from the piston it falls down inside the barrel and then the
piston starts to chew it up inside the barrel the leading cause for these valves getting
loose from the piston and getting inside the barrel is the retaining washer that actually
holds just the corner of the valve cup and that little retaining washer is super hard
what generally happens is the machine may be working in some pretty rough terrain and
he might run into something quite hard but doesn't move and that shock load going back
through forces everything to bottom out so it fractures the corner off the washer and
over time the valve will then start to work its way out of the piston so this washer is
not from this cylinder the one that came from the cylinder is actually missing a piece and
after it broke out that allowed that cup to walk its way out of the piston the valve followed
it and then everything got damaged from there so this level of damage would have only occurred
from continuous operation of the machine which leads me to believe the operator is not really
in sync with his machine or he doesn't really know what he's doing because he would have
noticed the blade falling over as he was trying to work it because the oil was bypassing through
the piston considering the amount of damage that is on the right hand cylinder the rod
is actually intact there was no damage to the rod at all and the left hand barrel has
also experienced a failure the barrel is quite damaged in there from metal going through
it depending on the configuration of the hydraulic system on the machine whether the two cylinders
actually share oil might explain why we have two failed cylinders but because they came
in as a pair I'm going to assume they're off the same machine so when these came in we
had exchange components ready to go we end up giving the customer a brand new right hand
cylinder because they needed the piston the gland and the barrel they decided to take
the entire cylinder even though they didn't need a new rod they've got a brand new one
to go back on their machine we also had a good condition left hand barrel that was sitting
on the shelf that they took as well so now that they're up and going again we need to
get these repaired so we can put them back into our exchange plate we will be rebuilding
the barrels to go back on our shelf we don't have the material at the moment so keep your
eye out for a future video where we rebuild those two we're not going to be repairing
the piston it is way too far gone to repair it they are cheap enough to buy from the genuine
manufacturer or aftermarket parts today we are going to be repairing the gland because
they are quite expensive to replace the customer has asked can we please repair this one and
they're going to put it on their shelf as a spare one for any future repairs they need
to do so what we're going to be using is flame spray in order to build up this area that's
all damaged after that's been built up we can then throw it in the lathe and machine
it back to spec for this repair what we need to do is reinstate
this o-ring groove you could just build up the area where the O-ring is going to live
but while we're here we're going to do the entire repair to make this as close to factory
as we can so all these areas that have got dents in them we're going to fill all them
up and machine it all back nice and flat there are a few methods you could use in order to
repair this this is cast iron so you could use a cast iron welding rod you could use
silicon bronze some of the issues with welding cast iron you can run into problems where
you do create hard spots where the arc is started and then stopped they can be difficult
to machine out if the cast iron is not a really good quality the welding rod just doesn't
take to the material very well it is quite difficult to find a filler material that will
stick to it so my preferred method to repair cast iron I'm going to use a UTP puddle gun
also known as a flame spray you can then apply concentrated heat to an area it adheres really
well to the cast iron and you can then build it from there and it doesn't create as many
hard spots as if you're going to use stick welding or MIG welding and I also like the
puddle gun because you can be very precise on where you put material you don't have to
put a massive layer in there in order to build it up you can also see if there's any material
trying to come like any impurities trying to come back through the layer you've just
put down you don't leave a big bubble there you can sort of work that material out with
electrodes it's quite difficult to do that especially in cast iron so the first thing
I'm going to do I'm going to give this a bit of a prep grind I'm going to remove any material
that has been pushed over an edge and is overlapping an area where I need to do a repair I will
then give it a quick wire brush just to remove any loose material from the top I don't need
to do any further cleaning on it because I will be applying the powder to a red hot surface
that is the key to this is getting it red hot and then applying the powder any other
impurities or oils will be burnt away before I start to lay the new material so that's the UTP handpiece setup you have
the main mixing body where you have your two valves the oxygen and acetylene that then
leads to your trigger for your hopper which passes the material down through the tip what
these guns do is they allow you to set a heat and it will be consistent once you have the
job to the correct temperature you can then pull the trigger which then allows material
down through the hopper it goes down through the tip and then gets applied onto the job
so I've decided to start with a smaller tip because they don't apply as much material
and you don't want to waste it it is quite expensive if I find I need more heat or I
need more material I can then upgrade to a larger tip but I generally start small and
then work my way up so I'm going to be using a machinable grade cast iron powder that powder
combined with the flame spray technique it avoids getting hard spots in the parent material
that can be difficult to machine later on so on a part this size you do want to
give it a preheat anything smaller you don't really have to because the heat will disperse
through the job and bring everything around it up to temperature but because this part
is so large if I wasn't to preheat it it could lead to cracking around the repair zone because
the heat will be dissipated through the part very fast so by bringing the whole part up
to temperature we're going to eliminate that risk of anything cracking this puddle gun uses oxygen and acetylene
as a fuel source even though I have preheated the part I am going to use the concentrated
heat from the puddle gun to get it red hot before I apply any material now that I've got that area red hot I can
start to apply material once that material then turns to a liquid I know it's then bonded
onto the part I can then move along the job slowly adding material if you do apply too
much powder you'll end up with voids and it won't bond to the part gravity will then take
hold and it will actually fall out of the job so I'm going to concentrate going back
and forth building up the areas where there's the most material missing after I get a bit
of body back in it I can then do the finer details applying material to create a nice
even layer [bang] [Laughter] righto guys so the flame spraying process
is now complete everything went pretty good pretty happy with how everything was applied
so we're going to let it cool down just sitting here on the bench there is no need to wrap
it in a blanket it's not going to rapidly cool down it is summer here so it is very
hot today there is no risk of it cracking because there is no crack through the job
all we did was fill up a void I've got no dramas with that sitting there for a couple hours
to cool off once that's cooled we can throw it in the lathe and get machining [squeak] [squeak] hold on hold on ohhh what ah huh it's a harness for a gopro
yeah right [giggle] press press that top button it should just
start recording there we go righto guys so that has cooled down now it's been
cooling down for pretty much most the day what I'm going to do now I am going to use
a wide wheel just to remove any of the residual dust and metal spray that's stuck to the surfaces
once I do that I'll take it over and set it up in a lathe right so you can see where there's
basically overspray this is where it hasn't stuck to anything because it never became
molten we can pretty much chip that off with a cold chisel and a hammer so I've just thrown a dial on that it does show that we do have
a little bit of run out there so I'm just going to bump that in with a copper faced
hammer hopefully we're going to get that to run a little bit better than what it is now
because there's no machined surface to reference from and all the other areas have been either
flame sprayed or are damaged I'm just going to make do with what I can so I've got that running tool within 0.03
of a mil a little bit over a thou which is pretty good considering the state that the
gland's in that's going to be just fine for this application so what I'm going to do now
I'm going to machine all the surfaces just to clean them up I'm then going to make sure
everything's round and running true and concentric and then we're going to machine the groove
so the O-ring and the backup ring fit in there perfectly what about that grey mark there that's
part of the original face that's where the valve hit it before it blew the valve apart
yeah that's fine we'll just clean that area there up chamfer that
come in and get that groove so I'm just going to angle my tool
around a little bit more I want to make the chamfer on the end of the gland a little bit
longer just to help the customer out when they go to install that it'll give them a
nice easy leading edge for the gland to then go into the barrel righto guys so I've got all those flame spray faces
machined back to spec or as close as they're going to get to spec there are a few areas
in the face of the gland that still have material missing there is a dent here from where the
valve has impacted the back of the gland there's also a few dents on the other side that I
don't know where they came from it might have been during the disassembly they're trying
to flog it off with a hammer those dents and surface imperfections aren't going to
make any difference to how this functions the important part of the repair was getting
that seal groove back to standard so we've got that sorted out now but while it's set
up and it's running pretty true we're just going to skim that just to clean it up righto guys so the repair is basically complete I'm
not entirely happy about this rusty area where the pipe center is so I'm going to take that
out take it back over the bench I'm going to use a conditioning wheel just to remove
that rust spot and then that will just look a million bucks righto guys that is the repair all completed I'm really
happy with how that turned out apart from the color discoloration between the original
gland and the material I added you would never know that there was a piece of material missing
and that it has been repaired after a couple of hundred hours cycling in the machine the
oil is going to stain that and you would never even know it was there what I'm going to do
now is paint is spray on some rust preventative strap it down to a pallet and get it back
to our customer thanks for watching are you ready yep how you going guys Kurtis
from Cutting Edge engineering so today oh [beep] hopefully we'll get that running a little bit more truer
truer hopefully we'll make it run a little bit more true is that a word that's not making English so there's also a lot of dabbing oh dabbage nearly said cabbage [Laughter] and then we'll machine the groove
right and then we'll machine the moo the move [giggle] this is extremely damaged uhmmmm hmmmm
haaa [ __ ] yeah we're gonna let that cool down after
that's cooled down we're gonna let that cool down once that's done wow [ __ ] what was I going to say then how are we starting that so [air compressor]
[giggle] smaller parts
[air compressor again] so the material i'm [air compressor AGAIN]
hmmmm [ __ ] off train someone wrote in a comment Brisbane to Gold Coast
trains are going to increase in frequency are you [ __ ] serious
[giggle] I hope not it's like every 15 minutes now what's it gonna
be every seven and a half minutes maybe [ __ ] off train ohhh [ __ ] off train
[ __ ] off train wow look at all this bits of steel in there there's part of the valve that's part of the valve as well okay [Laughter] hm come out [giggle]
can we retry that please are they meant to look mouldy
mm hmm oh helps if it's in gear
helps if it's in COG ugh [POP]
Jesus Christ [Laughter] how many endings can we get [giggle] and then that will just look a million bucks then that will just look amazing and that will just look salubrious and that repair will then look Bonza pfffftt [Laughter] okay that'll do okay stop that's enough hey hey hey calm down
no oi ya bugger just fricken heck is it going to see past your big head [giggle] there we go
hang on wait wait come back come back Homeless
hey [giggle] he's gone
