The cylinder liner is a cylindrical part, which is placed in the cylinder body hole of the body.The processing environment of cylinder liner is very harsh, so it requires high strength, rigidity, heat resistance and wear resistance of the material.Generally, the cylinder liner is made of wear-resisting alloy cast iron containing phosphorus or boron, but boron cast iron, high-phosphorus cast iron and other materials are of high hardness and difficult to process.With the innovation and research and development of the tool industry, at present, CBN tool is the effective material of cutting cylinder liner, this paper will focus on the cylinder liner material and the application of CBN tool in the field of cylinder liner.
1. Common material of Cylinder Liner
The cylinder liner is generally made of phosphorous or boron alloy cast iron, such as nodular cast iron, high phosphorous cast iron and alloy cast iron.Ductile iron is a kind of graphite with dense and strong pearlite matrix and spheroidal distribution. Cavitation corrosion resistance and wear resistance of it are also better than ordinary cast iron. However, the casting process is more complex than ordinary cast iron and the cost is higher.
High phosphorus cast iron cylinder liner
High phosphorus cast iron cylinder liner hardness, wear resistance is good, its wear resistance and nodular iron cylinder liner to close, technology is better than the ball model cast iron, it can also save time, and phosphorus can also change the corrosion resistance.However, high-phosphorus cast iron becomes brittle due to the increase of phosphorus content, and easy to produce shrinkage hole, resulting in waste.
Alloy Cast Iron Cylinder Liner
Alloy cast iron is obtained by adding nickel, chromium, copper and other alloying elements to cast iron. The addition of alloying elements can make the material structure uniform and pearlite compact, and can also promote the formation of high hardness carbides, further improve the strength, wear resistance and corrosion resistance of cast iron. The disadvantage of alloy cast iron is that it consumes precious metal when it is cast.In addition, the manufacturing cylinder liner material also contains boron cast iron, rare earth calcium cast iron, titanium vanadium cast iron, phosphorus vanadium cast iron and austrian type cast iron.n some enhanced internal combustion engines, nitrided steel is also used to make cylinder liners. That's because nitride steel is very good in heat and corrosion resistance.At 500 ℃, the hardness of nitrided layer decreased very little, which can guarantee its wear resistance in the processing temperatures.
2. Processing Technology of Cylinder Liner
(1) Dry Cutting Cylinder Liner
Casting Blanks -- Rough Machining -- Rough Boring -- Turning Arts Outside Circle -- Fine boring -- Semi-Fine Machining -- Fine machining -- Rough Honing -- Machining End Face and Outside Circle -- Rough Grinding Outside Circle -- Fine Grinding Outside Circle -- Fine Honing
(2) Wet Cutting Cylinder Liner
Casting Blank - Rough Machining - Rough Boring - Machining - Fine Boring - Fine Machining Water - Cutting - Rough Honing - Fine Machining - Honing
3. CBN Tool for Cylinder Liner Processing
At present, the cylinder liner is mostly made of boron cast iron, alloy cast iron and other wear - resistant cast iron.Since these cast iron has very high hard spots, cutting tools wear during machining.When cutting with carbide tool, cutting speed is low, tool wear is fast, it is difficult to improve working efficiency and machine efficiency, some materials are also difficult to grinding.As a new super - hard material tool, CBN tool has revolutionized the machining technology.It provides an economical and efficient cutting method for refractory materials such as cast iron.A large number of facts have proved that the CBN tool is in line with the direction of today's tool development - to improve life, improve cutting efficiency, reduce processing costs, ensure high precision and low roughness, to meet the processing requirements of difficult materials.As a pioneer in the localization of ultra-hard cutting Tools, Halnn Tools recommends two types of cutting tool materials for cylinder liner processing, which are bn-s300 and BNK30 materials respectively. Besides，BN-S300 material is the overall polycrystalline CBN cutter,which is applicable for coarse and fine machining.It also can cut the blank allowance of cylinder liner with large allowance and improve the machining efficiency.While BNK30 material is inlaid type CBN cutter, only its cutting edge part is CBN material. So BNK30 material is generally used for finishing process.It can ensure the dimensional accuracy and surface finish when machining the cylinder liner.
BNK30 mainly processes the following parts.
(1) Cutting Instead of Grinding, High Speed Cutting Wet Cylinder Liner Upper And Lower Belt.
(2) High Speed Cutting Cylinder Liner Cylindrical, Water Jacket Wall, Sealing Tank, Chamfering, Flat end.
(3) Finish The Outer Circle of Dry Type Cylinder Liner to Reduce The Machining Allowance and Working Procedure of Centerless Grinding.
4、 BNK30 Material Processing Boron Cast Iron Cylinder Liner Case
1. Common material of Cylinder Liner
The cylinder liner is generally made of phosphorous or boron alloy cast iron, such as nodular cast iron, high phosphorous cast iron and alloy cast iron.Ductile iron is a kind of graphite with dense and strong pearlite matrix and spheroidal distribution. Cavitation corrosion resistance and wear resistance of it are also better than ordinary cast iron. However, the casting process is more complex than ordinary cast iron and the cost is higher.
High phosphorus cast iron cylinder liner
High phosphorus cast iron cylinder liner hardness, wear resistance is good, its wear resistance and nodular iron cylinder liner to close, technology is better than the ball model cast iron, it can also save time, and phosphorus can also change the corrosion resistance.However, high-phosphorus cast iron becomes brittle due to the increase of phosphorus content, and easy to produce shrinkage hole, resulting in waste.
Alloy Cast Iron Cylinder Liner
Alloy cast iron is obtained by adding nickel, chromium, copper and other alloying elements to cast iron. The addition of alloying elements can make the material structure uniform and pearlite compact, and can also promote the formation of high hardness carbides, further improve the strength, wear resistance and corrosion resistance of cast iron. The disadvantage of alloy cast iron is that it consumes precious metal when it is cast.In addition, the manufacturing cylinder liner material also contains boron cast iron, rare earth calcium cast iron, titanium vanadium cast iron, phosphorus vanadium cast iron and austrian type cast iron.n some enhanced internal combustion engines, nitrided steel is also used to make cylinder liners. That's because nitride steel is very good in heat and corrosion resistance.At 500 ℃, the hardness of nitrided layer decreased very little, which can guarantee its wear resistance in the processing temperatures.
2. Processing Technology of Cylinder Liner
(1) Dry Cutting Cylinder Liner
Casting Blanks -- Rough Machining -- Rough Boring -- Turning Arts Outside Circle -- Fine boring -- Semi-Fine Machining -- Fine machining -- Rough Honing -- Machining End Face and Outside Circle -- Rough Grinding Outside Circle -- Fine Grinding Outside Circle -- Fine Honing
(2) Wet Cutting Cylinder Liner
Casting Blank - Rough Machining - Rough Boring - Machining - Fine Boring - Fine Machining Water - Cutting - Rough Honing - Fine Machining - Honing
3. CBN Tool for Cylinder Liner Processing
At present, the cylinder liner is mostly made of boron cast iron, alloy cast iron and other wear - resistant cast iron.Since these cast iron has very high hard spots, cutting tools wear during machining.When cutting with carbide tool, cutting speed is low, tool wear is fast, it is difficult to improve working efficiency and machine efficiency, some materials are also difficult to grinding.As a new super - hard material tool, CBN tool has revolutionized the machining technology.It provides an economical and efficient cutting method for refractory materials such as cast iron.A large number of facts have proved that the CBN tool is in line with the direction of today's tool development - to improve life, improve cutting efficiency, reduce processing costs, ensure high precision and low roughness, to meet the processing requirements of difficult materials.As a pioneer in the localization of ultra-hard cutting Tools, Halnn Tools recommends two types of cutting tool materials for cylinder liner processing, which are bn-s300 and BNK30 materials respectively. Besides，BN-S300 material is the overall polycrystalline CBN cutter,which is applicable for coarse and fine machining.It also can cut the blank allowance of cylinder liner with large allowance and improve the machining efficiency.While BNK30 material is inlaid type CBN cutter, only its cutting edge part is CBN material. So BNK30 material is generally used for finishing process.It can ensure the dimensional accuracy and surface finish when machining the cylinder liner.
BNK30 mainly processes the following parts.
(1) Cutting Instead of Grinding, High Speed Cutting Wet Cylinder Liner Upper And Lower Belt.
(2) High Speed Cutting Cylinder Liner Cylindrical, Water Jacket Wall, Sealing Tank, Chamfering, Flat end.
(3) Finish The Outer Circle of Dry Type Cylinder Liner to Reduce The Machining Allowance and Working Procedure of Centerless Grinding.
4、 BNK30 Material Processing Boron Cast Iron Cylinder Liner Case
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Machining Part：Boron alloy cast iron cylinder liner Cutting Tool：BNK30 SNGA120412-8S CuttingParameters: ap=0.3mm,Fr=0.2mm/r,Vc=850m/min,Wet Cutting |
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| Cutting Tool Material | Cutting Speed | Cutting Tool Life | Efficency |
| Halnn Tools BNK30 |
850m/min |
120 piece/blade | Double |
| Coated Carbide Cutter |
400m/min |
25 piece/blade | 25 piece/blade |