SERVICES
Bearing scrapping
A highly efficient technique exclusively used by Novexa
Novexa has developed a quick and efficient bearing scrapping method, through the use of portable electric equipment.
Wheras an intervention of trunnion bearing scrapping is usually carried out manually in 4 days, Novexa can provide this service in 4 to 5 hours.
We offer our services regarding bearing scrapping :
- Mill trunnion
- Pinion (fixed or mobile bearing)
- Kiln rollers
- All kinds of bearings type bronze, lead sleeve bearings and others
Our reliefs (entry and exit) are conforming to the rules in force of the industry :
- Relief of 2/1000 mm in diameter (entry and exit)
- Blue print control (1/7 on kiln rollers; 1/5 on trunnion bearings)
- Reliefs depend on the position of the pinion (up or down)
We manage our level measurement services (including theodolite, if axis are measured), upheaval of the mill, dismantling and reassembly of bearings, checking of trunnion roller expansion conditions on a free bearing and temperature probes as well as consulting services on the lubrication circuit.
Novexa is able to supply the saddle-bed support and appropriate shims for a re-leveling of a rotating tube).
Bearing scrapping - Example of intervention
Preparation and installation of the saddle-bed.
Decarterization of the bearing and upheaval of the whole through 2 hydraulic jacks.
Extraction of the bearing through a sling. This process can be carried out in approximately 4 à 6 hours maximum.
A preliminary measurement has been completed with the bearing already in place. A verification of the supporting surface and the state is necessary (blue print control).
-> Supporting surface maximum : 1/5 of bearing perimeter
-> Before machining, the load distribution represents more than3/5 of the bearing perimeter
The cutting is completed as a preparation for the machining process.
Supporting surface : 1/5
Entry relief : 2/1000 mm
Relief values up to 0,1 mm to 500 mm
Running machining process through machinery equipped with specific disks. This operation is carried out in our machine shop.
On-site machining by Novexa represents an advantage concerning intervention length which is 5 hours maximum for bearings.
A manual scrapping requires at least 40 hours.
Completed work.
No facet has occurred.
A blue print control and a relief control are then completed by Novexa.
In case of insufficient relief, a risk of warming up of the bearing exist.
The bearing might melt down quickly (over 120°C) and thus jam on the pinion.
The production halt period is thus long.
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Example of intervention in the cement industry
Intervention on a mill carried out in Guadeloupe and Martinique on 2 cement grinders.
Details of service :
- Supervision of the whole intervention site
- Dismantling and reassembly of the 2 trunnion bearings
- On-site remachining and scrapping
- Technical details of bearing : diameter 1 400 mm, width 500 mm
Characteristics after remachining :
- Relief of 3 mm at the entry of the bearing
- Measured clearance : 0,1 mm à 550 mm
- Contact pattern not exceeding 1/5 of the total surface
- Blue print control
Duration of intervention : 2.5 days
Result : temperature decline of 10°C after restart
Days gained compared to offers of competing companies : 6 jours
Novexa has always been an expert in managing wear speed. As a privileged partner in the industry, Novexa disposes of a long record of interventions regarding wear of gear, reprofiling, consulting and audit.
As of today, Novexa has developed its service range even further : our unique know-how applies to the wear of tires, alignment control measures and linked services ( bearing scrapping, welding repair etc.) as well.
SERVICES