Main parts of engine heads: valve guides, valve seat inserts, valve shims and adjusting pads are traditional company products.
They have been manufactured in a large range of items according to stringent quality specifications, and are used as OEM by major companies in the car, motorcycle, industrial and agricultural industries.
Thanks to the range of valve guides and valve seats in sintered steel, the company is able to offer a product that is self-lubricating with greater resistance to high temperatures, and consequently ideal for high-performance induction and supercharged engines.
Metelli Valve Guides are proposed with the following types of material:
G = pearlitic grey iron with good resistance to wear, suitable for applications with normal stress levels.
G1 = pearlitic grey iron with added phosphorus, which forms a lattice significantly enhancing resistance to wear even when lubrification is poor, thanks to its anti-friction properties.
G2 = grey cast iron with pearlitic laminar matrix combined with phosphorus and chromium. The phosphorus gives the grey cast iron resistance against wear, while the chromium improves its properties for use at high temperatures. Suitable for utilizations characterised by high strain.
B = aluminum brass alloy with high resistance to wear, good resistance to fatigue and corrosion, suitable for applications with medium stress levels.
B1 = phosphorus bronze alloy combining high resistance to wear and high thermal conductivity with good anti-friction properties; suitable for applications with high stress levels.
Cu = copper alloyith high hardness and thermal conductivity, and high resistance to wear and abrasion. Its excellent mechanical properties assure good resistance in heavy duty conditions.
Valve Guides in sintered steel - Sint 01, Sint 03, Sint 06
S01 = this copper molybdenum alloy is characterized by its elevated mechanical resistance that is also maintained at extremely high temperatures, which is joined by particles of lubricating material shrouded in alloy which tend to eliminate the cause of the phenomenon of wear due to shifting thus making it suitable for all types of use, even severe.
S03 = steel alloy featuring tin-phosphorus elements able to ensure mechanical strength and significant self-lubricating power. Compared to traditional material versions, Sint 03 valves guides do in fact show lower inertia in forming the hydrodynamic lubrication film on ignition and thus ensure excellent resistance to sliding wear.
Sint 03 sintered steel is able to maintain these properties even in heavy-duty working conditions such as those found in latest-generation engines.
These valve guides have been developed for all high-performance induction and supercharged engines – petrol, diesel and gas.
S06 = copper/sulphur alloy with good self-lubricating power and and wear resistance to glide under the working conditions to which the parts of high performance engines fueled with petrol, gas-oil or gas may be subject.
Valve Seat Inserts
Metelli Valve Seats Inserts are proposed with the following types of material:
G1,5 = sorbite-perlite cast iron matrix with good resistance to wear and hardness at high temperature. Composition:
MD02 = steel with 12% Cr, ledeburitic structure:
1) Very hith resistence to wear due to its structure based on complex carbides;
2) Good resistance to shock;
3) Good resistance and no deformation in hot condition;
4) Very good resistance to heat oxidation at temparatures over 700° C;
5) Brinell hardness = 400-425.
Valve Seat Inserts in sintered steel - Sint 04 /Sint 07
S04 = in an ongoing quest for high performances, associated with the modern ecological need to reduce emissions, major manufacturers have equipped their engines with valve seat inserts in sintered material.
The sintering process makes it possible to achieve alloys with thus-far incompatible properties, such as outstanding hardness and excellent workability.
For these reasons, Metelli Co. has produced valve seat inserts made of Cobalt-Molybdenum sintered steel alloy containing solid material parts in the structure that ensure lubricating power even at high temperatures (900°C).
Sint 04 sintered steel is also distinguished by high wear resistance both in terms of abrasion and of pounding-in and is compatible with heads made of both aluminum and cast-iron, with different draught (interference).
The Sint 04 alloy valve seat ring has been developed for all high-performance induction and supercharged engines - petrol, diesel and gas.
S07 = cobalt-molybdenum steel alloy characterized by copper infiltration. The result is a unique steel/copper structure that increases density with a consequent great improvement, during operation and at any temperature.
Its mechanical performance: tensile strength, elongation, shock resistance, wear resistance and hammering resistance, even in heavy-duty operating conditions.
Valve Shims and Adjusting Pads
Metelli Valve Shims and Adjusting Pads are proposed with the following types of material:
A = Cemented and hardened steel.
AS = Special steel.
AN = Normal steel.