Cylinder Liners
Centrifugal Casted Cylinder Liners
Duraldur produces in his Italian plant a very significant volume of finished centrifugal cast iron cylinder liners for engine blocks. The liners are obtained by centrifugal casting process in steel moulds.
The materials used are different lamellar cast irons with chemical composition following the required international standards:
- EN-GJL-200;
- EN-GJL-250;
- EN-GJL-320.
The liners are machined and honed to meet the last fuel consumption and gas emission requirements by international standard.
For special applications some surface treatments can be carried out in and outside specialized sub-supplier facilities (e.g. nitriding, chroming, plasma coating). For high performance engines the liners can be produced in spheroidal or vermicular cast iron.
In particular, the standards used are:
- EN-GJV-500;
- EN-GJS-600;
- EN-GJS-700.
Steel Liners
Where even higher mechanical properties are required combined with limited resistance sections, you may need steel liners. The steel liners are obtained by machining of normalized extruded tubes which after a roughing operation are quenched and tempered.
At the end of the heat treatment the liner are finished outside by machining and inside by honing. The materials used for these particular are:
- 20MnV6
- 42CrMo4
Even on these components it is possible to carry out surface treatments designed to decrease the wear or corrosion of the particular.
Steel Liners
Where even higher mechanical properties are required combined with limited resistance sections, you may need steel liners. The steel liners are obtained by machining of normalized extruded tubes which after a roughing operation are quenched and tempered.
At the end of the heat treatment the liner are finished outside by machining and inside by honing. The materials used for these particular are:
- 20MnV6
- 42CrMo4
Even on these components it is possible to carry out surface treatments designed to decrease the wear or corrosion of the particular.
Aluminium Extruded Liner
Experience gained in the forging pistons process is also used to offer aluminum extruded liners.
The Al-Cu and Al-Si alloys used, can be the same used in forged pistons production. Furthermore, can be used high silicon aluminum alloys, produced by special process, for race engine application.
The liners after marching process are coated inside with material that increase the hardness and the wear resistance of the surface, and then the liners are honed to satisfy the consumption and gas emission required by Customer’s standards.