There are many different specifications governing the use and production of grey iron. At Matrix Iron Foundry, we produce grey iron in accordance with American Society of Testing and Materials (ASTM) A48, IS:210 1978 and BS EN 124:1994 as mentioned below.
ASTM A48 covers a class of cast irons that are intended for general use applications.
Grades of ASTM A48 Grey Iron Produced at Matrix Iron Foundry
| ASTM A48 Grade | Ultimate Tensile Strength (UTS) | Brinell Hardness |
|---|---|---|
| Class 30 | 30,000 p.s.i | 187-241 |
| Class 35 | 35,000 p.s.i. | 207-255 |
| Class 40 | 40,000 p.s.i | 217-269 |
*UTS values are minimums required by ASTM for an independently cast tensile test bar sample. Casting strength may be more or less depending on cast section thickness. Consult ASTM A48 or Matrix Iron Foundry for more information.
| Desirable properties | Common Applications |
|---|---|
| Excellent vibration dampening capability | Brake drums, rotors and clutch components |
| High compressive strength | Engine blocks, cylinder liners and heads |
| Good machinability | Pulleys, sheaves and idler wheels |
| Exceptional heat transfer | Gears |
| Low cost alternative to other engineering materials | Hydraulic valves and components |
Although A48 class 35 grey iron is a common material, and its application is very wide, but its total production volume is not large compared with other cast iron materials. It is because its hardness is difficult to control in production. If the brinell hardness is higher than 200, then it will bring difficulty to drill and milling machining. Lower than 200 will cause the grade reduced to class 30. Therefore, if ASTM A48 class 30 could meet your requirements of application, then it will be the better choice than class 35.
*SPECIFICATION SHEET FOR MECHANICAL & CHEMICAL COMPOSITION OF DIFF GRADES OF CAST IRON AS PER ASTM A48 GRADE: -
| GRADE | CLASS 30 | CLASS 35 | CLASS 40 | CLASS 45 | CLASS 50 |
|---|---|---|---|---|---|
| % C | 3.5 | 3.4 | 3.2 | 3.1 | 3.0 |
| % SI | 2 | 1.7 | 1.5 | 1.45 | 1.40 |
| % MN | 0.65 | 0.7 | 0.8 | 0.9 | 0.9 |
| % P | MAX 0.08 | MAX 0.08 | MAX 0.08 | MAX 0.08 | MAX 0.08 |
| % S | 0.12 | 0.12 | 0.12 | 0.12 | 0.12 |
| Chromium | = | = | = | = | 0.35 |
| Molybdenum | = | = | = | = | 0.30 |
| BHN | 170 - 241 | 187 - 241 | 187 - 255 | 196 - 255 | 196 - 269 |
| TENSILE STRENGTH (PSI) | 30,000 | 35,000 | 40,000 | 45,000 | 50,000 |
| Minimum Wall Thickness | 3/16" | 3/8" | 1/2" | 5/8" | 3/4" |
| * On a 1.2" ASTM A-48B Test Bar | |||||
*SPECIFICATION SHEET FOR MECHANICAL & CHEMICAL COMPOSITION OF DIFF GRADES OF CAST IRON AS PER IS:210: 1978 SI Unit -
| GRADE | FG 100 | FG 150 | FG 200 | FG 260 |
|---|---|---|---|---|
| % C | 3.5 - 3.8 | 3.4 - 3.7 | 3.2 - 3.5 | 3.1 - 3.4 |
| % SI | 2.3 - 2.8 | 2.1 - 2.6 | 1.8 - 2.3 | 1.6 - 2.1 |
| % MN | 0.4 - 0.8 | 0.5 - 0.8 | 0.6 - 0.8 | 0.6 - 0.8 |
| % P | MAX 0.2 | MAX 0.2 | MAX 0.2 | MAX 0.15 |
| % S | 0.06 - 0.15 | 0.06 - 0.15 | 0.06 - 0.15 | 0.06 - 0.12 |
| C EQV. | 4.2 - 4.6 | 4.0 - 4.3 | 3.8 - 4.1 | 3.6 - 3.9 |
| BHN | 120 - 140 | 130 - 150 | 140 - 170 | 170 - 220 |
| TENSILE STRENGTH | 12 kg/mm2 | 15 kg/mm2 | 20 kg/mm2 | 25 kg/mm2 |
BS EN 124:1994
The applicable British Standard in the UK for access covers and gully grates is BS EN 124:1994. This standard divides access covers and gully grates into a number of classes by static test load.
Group 1 – minimum Class A15 Access covers and gratings capable of withstanding a 1.5 tonnes test load. For use in areas where only pedestrians have access.
Group 2 – minimum Class B125 Access covers and gratings capable of withstanding a 12.5 tonnes test load. For use in car parks and pedestrian areas where only occasional vehicular access is likely.
Group 3 – minimum Class C250 Access covers and gratings capable of withstanding a 25 tonnes test load. For use in car parks, forecourts, industrial sites and areas with slow moving traffic also in highway locations up to 500mm from the kerb and up to 200mm into the verge, excluding motorways.
Group 4 – minimum Class D400 Access covers and gratings capable of withstanding a 40 tonnes test load. For use in areas where cars and lorries have access, including carriageways, hard shoulders and pedestrian areas.
| Size(mm) | Load Ability | Approx Weight(KG) |
|---|---|---|
| 300 | A15 | 5 |
| 400 | A15 | 7 |
| 500 | B125 | 20 |
| 500 | C250 | 23 |
| 600 | B125 | 26 |
| 600 | C250 | 37 |
| 600 | D400 | 50 |
| 650 | B125 | 40 |
| 650 | C250 | 44 |
| 650 | D400 | 56 |
| 700 | A15 | 32 |
| 700 | B125 | 41 |
| 700 | C250 | 49 |
| 700 | D400 | 70 |
| 750 | B125 | 47 |
| 750 | C250 | 69 |
| 750 | D400 | 78 |
| 760 | C250 | 66 |
| 760 | D400 | 80 |
| 800 | B125 | 66 |
| 800 | C250 | 75 |
| 900 | C250 | 76 |
| 900 | D400 | 85 |
Surface Size Square & Rectangle Manhole Cover
| Size(mm) | Load Ability | Approx Weight(KG) |
|---|---|---|
| 230 * 280 | B50 | 8 |
| 300 * 300 | A15 | 7 |
| 300 * 300 | B125 | 11.8 |
| 300 * 400 | B125 | 14 |
| 300 * 500 | B125 | 17 |
| 300 * 500 | C250 | 19 |
| 400 * 400 | A15 | 20 |
| 400 * 400 | B50 | 21 |
| 400 * 600 | A15 | 23 |
| 400 * 600 | B125 | 26 |
| 450 * 900 | A15 | 50 |
| 500 * 500 | A15 | 20 |
| 500 * 500 | B125 | 23 |
| 500 * 500 | C250 | 33 |
| 500 * 700 | A15 | 41 |
| 500 * 700 | B125 | 55.6 |
| 500 * 700 | C250 | 71.2 |
| 590 * 590 | B125 | 39.5 |
| 600 * 600 | A15 | 35 |
| 600 * 600 | B125 | 54 |
| 600 * 600 | C250 | 57 |
| 600 * 600 | D400 | 75 |
| 600 * 900 | A15 | 52 |
| 600 * 900 | B125 | 59 |
| 600 * 900 | C250 | 93 |
| 640 * 640 | B125 | 58 |
| 640 * 640 | C250 | 69 |
| 700 * 700 | A15 | 55 |
| 700 * 700 | B125 | 87 |
| 700 * 700 | C250 | 90 |
| 700 * 900 | B125 | 120 |
| 700 * 900 | C250 | 138 |
| 700 * 1200 | B125 | 130 |
| 700 * 1200 | C250 | 145 |
| 760 * 760 | B125 | 74 |
| 760 * 760 | C250 | 76 |
| 790 * 1000 | B125 | 80 |
| 790 * 1000 | C250 | 138 |
| 800 * 800 | A15 | 87 |
| 800 * 800 | B125 | 105 |
| 800 * 800 | C250 | 113 |
| 900 * 900 | B125 | 93 |
| 900 * 900 | C250 | 119 |
| 900 * 1100 | B125 | 172 |
| 900 * 1100 | C250 | 182 |
| 1000 * 1200 | B125 | 185 |
| 1000 * 1200 | C250 | 187 |