Characteristics and application of gray iron castings
HT100 (EN-GJL-100)
Characteristics: It is a low-strength cast iron part with good casting performance, simple process, low stress, no artificial aging treatment, and excellent vibration reduction.
Application: It is suitable for manufacturing unimportant mechanical structural parts with simple shape, low strength requirements, and no special requirements for friction or wear, such as covers, covers, oil pans, hand wheels, hand racks, bottom plates and heavy hammers.
HT150 (EN-GJL-150)
Characteristics: It is a medium-strength cast iron part with good casting performance, simple process, low stress, no artificial aging treatment, certain mechanical strength and good vibration reduction.
Application: Suitable for manufacturing mechanical castings that withstand medium stress, such as supports, bases, covers, gear boxes, tool rests and seats, ordinary machine tool beds, and other parts that do not require high strength, do not allow large deformation and cannot be artificially aged, workbenches, pipe fittings with low working pressure, and wear-resistant sleeves with a wall thickness of ≤30mm; this grade can also be used to manufacture chemical parts that work in weakly corrosive media such as soda ash and dyes.
HT200 (EN-GJL-200), HT250 (EN-GJL-250)
Characteristics: It is a high-strength cast iron part with good strength, wear resistance, heat resistance, good shock absorption, good casting performance, and requires artificial aging treatment.
Application: Suitable for manufacturing parts that bear large bending stress (<2940N/cm2) and unit area pressure between friction surfaces>49N/cm2, as well as important castings in general machinery manufacturing, such as cylinders, gears, machine bases, metal cutting machine tool beds and bed surfaces; cylinder blocks, cylinder heads, pistons, brake wheels, coupling plates, and piston rings of gasoline (diesel) engines of automobiles and tractors; inspection workpieces with measuring planes, such as scribing plates and levels. In addition, it is also suitable for manufacturing oil cylinders, containers, pump bodies and valves, etc. that bear medium pressure (<785N/cm2) and have a certain ability to resist corrosive media.
HT300 (EN-GJL-300), HT350 (EN-GJL-350)
Characteristics: It is a high-strength, high-wear-resistant cast iron part with high strength and good wear resistance, but it has a large tendency to white spots and poor casting performance, and requires artificial aging treatment.
Application: Suitable for manufacturing parts that are subjected to high bending stress (<4900N/cm2) and tensile stress and pressure per unit area between friction surfaces ≥196N/cm2, such as machine tool bed guide rails, lathes, punching machines and other heavy machinery with large force, machine bases, spindle boxes, gears, cams, etc.: large engine crankshafts, cylinder blocks (covers), etc.; hot forging dies, cold punching dies and parts that require surface treatment, etc. In addition, it can also manufacture parts such as high-pressure pump bodies, valve bodies and hydraulic cylinders that require high air tightness.
Characteristics and application of ductile iron castings
QT400-18 (EN-GJS-400–18), QT400-15 (EN-GJS-400–15)
Features: Good weldability and machinability, high impact toughness at room temperature, low brittle transition temperature, and good low-temperature toughness.
Application: Suitable for manufacturing parts requiring high strength and toughness, such as traction frames, drive axle housings, clutch housings and forks, spring lugs, and automobile chassis suspension parts on automobiles and tractors; in general machinery manufacturing, such as valve bodies, valve discs, and brackets of 1.6~6.4MPa valves, high and low pressure cylinders and gas pipes on compressors that withstand a certain temperature; in agricultural implement manufacturing, such as heavy-duty machine-driven five-furrow plows, light two-furrow plows, plow supports, plow side plates, traction frames, and guide frames on harvesters and mowers, differential housings, blade guards, etc.; others such as railway pads, motor housings, gear boxes, turbine housings, etc.
QT450-10 (EN-GJS-450–10)
Characteristics: Good weldability and machinability, slightly lower plasticity than QT400-18 (EN-GJS-400–18), but better strength and low-energy impact force than QT400-18 (EN-GJS-400–18).
Application: Same as QT400-18 (EN-GJS-400–18)
QT500-7 (EN-GJS-500–7)
Characteristics: Medium strength and plasticity, good machinability.
Application: Suitable for manufacturing internal combustion engine oil pump gears, steam turbine medium-temperature cylinder partitions, turbine valve bodies, railway locomotive vehicle bearings, machine frames, transmission shafts, sprockets, flywheels, motor frames, jack seats, etc.
QT600-3 (EN-GJS-600–3)
Features: medium to high strength, good wear resistance, but low plasticity.
Application: Suitable for manufacturing internal combustion engine parts, such as crankshafts of 4~3000kW diesel and gasoline engines, camshafts, cylinder liners, connecting rods and intake and exhaust valve seats of some light diesel and gasoline engines; agricultural machinery, such as pedal thresher racks, light load gears, animal-powered plowshares; machine tools, such as spindles of some grinders, milling machines, and lathes; general machinery parts, such as crankshafts, cylinder blocks, and cylinder liners of air conditioners, air compressors, refrigerators, oxygen generators, and pumps; metallurgy, mining, and lifting machinery, such as ball mill gear shafts, mine wheels, and bridge crane large and small car rollers.
QT700-2 (EN-GJS-700–2), QT800-2 (EN-GJS-800–2)
Characteristics: high strength and wear resistance, but low toughness and plasticity.
Application: basically the same as QT600-3 (EN-GJS-600–3)
QT900-2 (EN-GJS-900–2)
Characteristics: high strength and wear resistance, high bending fatigue strength, contact fatigue strength and certain toughness.
Application: suitable for manufacturing parts of agricultural machinery such as plowshares, harrow blades, low-speed agricultural bearing rings: automotive parts such as bevel gears, steering knuckles, transmission shafts, etc.; reduction gears on tractors; parts of internal combustion engines such as camshafts, crankshafts, etc.
Post time: Jul-25-2025