Tin Bronze (North American UNS C90500, German CuSn10Zn, British G1) for piston airplane enginesCast Iron is a general term applied to a wide range of iron carbon alloys. Their carbon content is such as to cause some liquid of eutectic composition to solidify. The maximum carbon content is therefore about 2% while the practical maximum is about 4.3%Cast Iron should not be thought of as metal having single element. It should at least posses’ six elements. These are iron, carbon, silicon, manganese, phosphorus and sulphur.Some of the important mechanical properties
- Brinell Hardness Number (b.h.n) = 150 to 225
- It is a brittle material.
- It cannot be beaten in sheets or rolled or forged. Hence it is not a malleable material
Various types of Cast Iron are as follows:
- Grey Cast Iron
- White Cast Iron
- Mottled Cast Iron
- Malleable Cast Iron
- Spheroidal Grey Iron (s.g.iron)
- Inoculated Cast Iron
- Alloy Cast Iron
Addition of nickel to cast iron produces fine grains, helps formation of graphite and prevents formation of white hard iron nickel & copper ensure an austenitic structure. Chromium and silicon add resistance to scaling. The microstructure of iron is stabilized and formation of fine graphite is promoted by the addition of chromium. The matrix of cast iron is strengthened through promotion of the fine pearlite by the addition of molybdenum.
Valves developed from CuZnAl-alloy & grey cast iron alloy with high phosphorous content to offer high wear resistance as well as improver the years working properties in poor lubrication conditions. The inner bore of these valve guides is finished to perfect size, not usually done by competitors.
CuZnAl-alloy Guides are with excellent wear resistance and low coefficient of friction. Used for highest stressed guides. While developing these valve guides, we pay care full attention to the accurate dimensions, so that they could meet with the OEM standards.
Our valve guide has hardness in range of 160 225 BHN. ValveGuide has microstructure of matrix pearlite with 5% free ferrite. We also provide thread or spiral in inner diameter of valve guide to retain oil for long time between valve and valve guide & increase life both. Our valve guide are grounded to a surface finish 0.80 micro ra value on its outer dia & maintain outer diameter within tolerance of 12 microns. Our valve guide has Super Finish Bore.