screw is stuck

[Chris]

Hello everyone, i found you because of some problems, and with 20+ years of experience I hope i may help others as well.

First Off i am working on a 310 Krauss Maffei with a 70 MM screw Diameter.

I am trying to get the screw out of the machine, but i can not even get it to come out of the splines on the end of the screw.

the coupling is off even with material in the screw, it will still pull it back, but only moving the screw less the 1/8 of an inch.

can anyone help ?:confused:

i would be glad to provide any more details, just let me know.

thanks for any and all help

Chris

[Pilot]

Hi Chris, which machine..... KM310 MX???

[Chris]

hi Pilot,

Thanks for getting back to me.

it is a 1995
KM280-1650B3

let me know if you would like any other info.

thanks again
Chris

[Pilot]

OK, I will try to help ...... but it is too small machine for me :-)

If I understood, you disconect the screw from piston, am I right? For this operation is beter to fill PE into barrel .... it is like wax :-) ..... Is your screw completely free from piston ???

[Pilot]

please see PDF
Sometimes (if the screw is free - not fixed properly) during production is "knocking" on spacer "67" and it makes a damaging on the end (close to splines) - shivering, Due this defect is impossible to go back through splines :-(

[Chris]

Thank you.

I already had this print, but do you know what the reference points are for 87, 64, 50, 15, 65, 58.

help, lol

If it cannot go through the splines, not what i really wanted to hear.

how to overcome this ?

[Pilot]

OK
1. release small screw 87 (2x)
2. release flange 64 (be carefull it is oposite thread - during plastication it is tightening) - if you will assembled this item back, do not use a tool !!!! only by hand!!!
3. take out two halfmoons 65 are connected by O-ring 58
4. take a cigaret

5. screw is free now ... is sitting in the splines only.

6, Do not touch item 50, 15. it is a part of injection piston.

In Case, that screw cannot go through splines, you can disconect whole injection cylinder from machine frame and take out this unit incl. screw out. Next step is open cylinder and take out item 12 with jammed screw. On this you can apply hard force :-)
OR
to buy new assy group :-)

[Chris]

OK
1. release small screw 87 (2x)
2. release flange 64 (be carefull it is oposite thread - during plastication it is tightening) - if you will assembled this item back, do not use a tool !!!! only by hand!!!
3. take out two halfmoons 65 are connected by O-ring 58
4. take a cigaret

5. screw is free now ... is sitting in the splines only.

6, Do not touch item 50, 15. it is a part of injection piston.

In Case, that screw cannot go through splines, you can disconect whole injection cylinder from machine frame and take out this unit incl. screw out. Next step is open cylinder and take out item 12 with jammed screw. On this you can apply hard force :-)
OR
to buy new assy group :-)

Well, thanks for the explanation.
We are doing everything right, to the extent that we can anyways. I believe you are correct with the back of the screw being hit on(now mushroomed) by the injection unit.

I am not sure where we are going from here, but i do want to thank you for the help and advice.

If you have any more suggestions, i will gladly listen.

thanks
Chris

[Pilot]

I hope, that you will have a successsssss :-)
Give me a feedback

Pilot

[Shank]

Hi Chris!! Had the same problem with my Krauss Maffei's. Chris your screwed lol!!! The splines are mushroomed over. Save yourself the time. Cut the screw off and drill it out. Sorry to give you the bad news!!
Shank

[Chris]

Hello Pilot and shank,

Just wanted to give some feedback as to what we have had to do.

we cut the screw with cutting torches

Made up a plate to mount a MAG drill on and drilled the screw out of splines

made a bottom drill out of the drill bit to get as close as we could to the end of the screw(should have gotten way closer on one of the machines)

used a die grinder to cut grooves in what was left of the screw to cut down the edge of splines

used chisels and BFH until all pieces came out

[Pilot]

Hi Chris,

thank you for nice pictures. You made a gooooood job :-)
Is the machine running now?

[Chris]

hey pilot,

yes 1 of the machines is running parts.

now to take the extruder motor off to have it rebuilt, its leaking oil like no tomorrow and has no torque.

chris