Saturday, 10 November 2018


Crankshaft materials can be easily designed, mechanized and processed and have sufficient strength, strength, hardness and fatigue resistance. The crankshaft is made of steel by forging or casting. The main bearing and connecting rod assemblies are made of babbit, tin and lead alloy. Forged crankshafts are stronger than cast crankshafts, but more expensive. Forged crankshafts are made of SAE 1045 steel or similar. Forging is a very dense and resistant wood with the eyes parallel to the direction of the main tension. The crankshafts are made of steel, modular cast iron or moldable cast iron. The main advantage of the casting process is that the material and machining costs of the crankshaft are reduced as the crankshaft can be approached to the desired shape.

including counterweights. Cast iron cranks are able to support loads from all directions, because the structure of the metal particles is uniform and
random. The counterweights of cast crankshafts are slightly larger than those of forged crankshafts, because the cast metal is less dense and therefore slightly lighter.

The car used in the past was often used to get everything good. However, from the beginning of nodular cast irons and search engine updates, the materials used as weights are mounted. Only for a large load of paperwork.

Manganese Molybdenum Steel

This is a low price for machining and is used for crankshafts of the fuel engine. It consists of 0.38% carbon, 1.5% manganese, 0.3% molybdenum and the residue. Then the machine is repaired with a gas tank with a volume of 1123 K, a length of 973 K, which leads to an increase of approximately 250 Brinell

1% chromium-molybdenum steel

This forged steel is used in diesel and petrol crankshafts for medium and heavy loads. The alloy composition is 0.4% carbon, 1.2% chromium, 0.3% molybdenum and iron. The steel is heat-treated from 1123 K and then to 953 K. This results in a hardness of about 280 Brinell numbers.

2.5% Nickel Chromium Molybdenum Steel

This is selected for high-performance steel diesel engines. The alloy has the following composition: 0.31% carbon, 2.5% nickel, 0.65% chromium, 0.55% molybdenum and iron. The steel is first heat-treated by freezing the oil at a temperature of 1003 K and then reset to a temperature not exceeding 933 K. This surface hardness is 300 Brinell.
3% chromium-molybdenum or 1.5% chromium-aluminum-molybdenum steel

These forged steels are used on crankshafts of diesel engines that are suitable for carrying hard materials with high fatigue strength. The alloy composition is 0.15% carbon, 3% chromium and 0.5% molybdenum or 0.3% carbon, 1.5% chromium, 1.1% aluminum and 0.2% molybdenum. The initial heat treatment of both steels consists of stopping the oil at 1193 K and 883 K or at 1163 K and at 963 K for both steels. The axes are cured by diffusion by means of nitride, which allows nitrogen to be absorbed in the surface layers
Ductile Iron

These cast gels are also known as spinal graphite irons or spheroidal graphite. These gray castings have 3-4% carbon and 1.8-2.8% silicon, and the graphite nodes are dispersed in the Pearlit matrix instead of false graphite. To achieve this structure, about 0.02% residual cerium or 0.05% residual niagnes, or both, is added to the alloy to remove sulfur and many small spheroids are formed in the cast material. The surface hardness of spheroidal iron is higher than that of steels of similar strength and hardness of 250-300 and 200-250 Brinell. Flame or induction hardening can create a surface with 550-580 Brinell numbers.

Preferred properties of spheroidal iron are gray iron (i.e., low melting point, good fluidity and pourability, excellent machinability and abrasion resistance), and the mechanical properties of the steel (i.e., relatively high strength, hardness, strength, functionality and hardening properties).

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