Re: Improvement Of Impact Crusher In A Cement Plant
Frank
It appears that you are at the limits or exceeding the limits of this machine.
1000 mm infeed down to 75 mm product is about a 13:1 crushing ratio which is quite high for an impactor. 1000 mm infeed is the maximum feed size that Aubema will allow as per their website. www.aubema.com.
What is the gap distance you are setting between the rotor and impact plates?
You may have to live with continuous maintenance or spec a larger replacement machine.
Having a spare rotor ready to drop in during a regular maintenance interval would be recommended. Then the removed rotor can be rebuilt easier in a rebuild shop and ready for the next time. Any bad wear plates can be replaced at the same time.
Gary Blenkhorn ■
Gary Blenkhorn
President - Bulk Handlng Technology Inc.
Email: garyblenkhorn@gmail.com
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Offering Conveyor Design Services, Conveyor Transfer Design Services and SolidWorks Design Services for equipment layouts.
Re: Improvement Of Impact Crusher In A Cement Plant
Dear Gary,
it seems that we reach the limits of the machine, but these are the contract figures.
We accept maybe 90% to 90 mm, but we omly can reach it for a short time.
Frank Hahn ■
Crsuher
We have a Hazemag crusher for limestone
design 800tph, actual 1100tph
feed size 1500 to minus 100mm
Have U spoken to the OEM re the issues
We get 6 weeks (80hrs/week) before we have to turn the blow bars
We initally had poor bar wear at the tips. The OEM suggested that we remove every second blow bar. The reason being that the rocks were not entering the blow bar zone far enough by the time the blow bar struck the rocks.
This is important so that the struck rocks are thrown out at the incoming feed at the right angle ie impact action.
We did this will the right result.
The rotor should not be wearing at all. Is the rotor slowing down under load...effecting the rock penetration.
Also..we have 2 impact zones - important to set the first one larger than the second.
The blow bars are OEM - Manganese steel..work hardens. We have not looked at others as the costs is not that much.
No crusher supplier has been serious about safety...we have had 2 LTIs with ours.
We were given a blow bar turning device but use a mobile crane instead.
One big safety issue is de bogging a bogged crusher with rocks still on the feeder pan conveyor!!!.
If U are getting broken pans - check for pan under support rails.
Cheers
James ■
Incredible~~~Hoho,13:1 Crushing Ratio
1000 mm infeed down to 75 mm product is about a 13:1 crushing ratio which is very very difficult for a crusher to reach that.
Normally, the crshing ratio is 5:1 or 6:1 if you only use a primary crusher without the secondary or ternary crusher. if you do like this ,it really make a wrong decision.
In my opinion, you can do like this
primary crusher: infeed 1000,outfeed 300
secondary crusher:infeed 300,outfeed 75
I'm in China ,and I'd like see that machine .maybe I can give you some comments.
my email:
hunterjiang@eyou.com ■
Impact Crusher
Dear All,
There are two parameters,
1) Impactors are expected to have crushing ratio 1 to 7, more thyan this will be a big strain on the impactor. Obvoiusly wear replacement will be more.
2) Limestone seems to be hard which might be one more reason to the problem
Neelesh ■
Re: Improvement Of Impact Crusher In A Cement Plant
Frank
I have dealt with 250tph Aubema impact crushers for limestone/dolomite. (Size reduction from 100mm to -20mm). Because of high rpm, any ununiform wear of hammers would cause heavy vibrations and subsequent abnormal failures.
The following factors had favourable effect on performance:
1.Uniform feeding over full length of rotor.
2.Reversible running of impactor to make wear of hammer heads more uniform and for longer life.
3.Ensuring right quality of material of hammers. (some poorly cast hammer sets got damaged in a few hours of running!)
4. A spare rotor ready for replacement at site will help reduce danger to maintenance personnel. ■
Crusher Performance Improvement
Frank
The Impactor for the appplication you had described seems a wrong choice. An impactor for the Feed to product ratio described can not perhaps gurantee trouble free operation. ■
Improvement of Impact Crusher in a cement plant
Dear All,
please give me some suggestions to improve the function of an impact crusher delivered in 2003 by AUBEMA to a chinese Cement Plant.
The first commissioning was: 22 march, 2004
The rotor was already repaired several time, after the big damages due to that the blow bars were broken and destroy the lining and the grinding path.
Material: Limestone
Feeding size:0 - 1000 mm
Final size: 0 - 75 mm
Hardness: 42 - 94 mpa
Capacity: 600 - 700 t/h
Rotor dia: 1600 mm
Rotor length:2000 mm
The problems are:
1.) The machine has a very high wear rate, the lifetime of the blow bars is only 400 hours
2.) The groove in the rotor to hold the blow bar is worn out after half year operation.
3.) The blow bars are very difficult to change, and its very dangerous to do the job for the maintenance staff.
4.) The noses of the blow bars are broken and the left and the right end.
5.) The aprons have cracks.
6.) Etc...
If you need picture for your better judgement, please contact me any time.
Thanks
Frank Hahn ■