Penetration grade or viscosity grade: two ways to name the same binder
Most of the confusion in bitumen enquiries comes from comparing names that belong to different standards:
- Penetration grade (40/50, 60/70, 85/100). The depth, in tenths of a millimetre, that a 100 g needle sinks into the bitumen in five seconds at 25 °C (ASTM D-5). A lower number is a harder binder.
- Viscosity grade (VG-10 to VG-40). India's IS 73 classifies paving bitumen by absolute viscosity at 60 °C, the temperature of a road surface in summer. VG-30 is the grade most Indian highway work is specified in.
The two systems overlap but do not map one-to-one: two bitumens with the same penetration can have different viscosities at 60 °C. A 60/70 lot only becomes VG-30 by being tested to IS 73, not by being relabelled. If your tender specifies VG-30, send the specification and we will confirm whether a lot tested to IS 73 can be offered.
Choosing a penetration grade by climate and traffic
Choose on the pavement temperature range and axle loading, not on price per tonne: the wrong grade ruts in summer or cracks in winter.
| Grade | Penetration at 25 °C | Softening point | Typical use |
|---|---|---|---|
| Bitumen 40/50 | 40–50 | 52–60 °C | Hot climates, heavy axle loads |
| Bitumen 50/70 | 50–70 | 44–56 °C | Temperate climates, general paving |
| Bitumen 60/70 | 60–70 | 46 °C min | The global reference paving grade |
| Bitumen 60/90 | 60–90 | 40–60 °C | General road works, wide band |
| Bitumen 85/100 | 85–100 | 45–52 °C | Cold climates, surface dressing |
What the 60/70 certificate shows
Passing every test in the drum is not enough. The thin-film oven test (TFOT) heats a thin film of the binder to simulate ageing in the asphalt plant mixer, then re-tests it. A binder that fails TFOT turns brittle in the road.
| Property | Result | Limit |
|---|---|---|
| Penetration at 25 °C, 0.1 mm | 66 | 60–70 |
| Softening point | 48 °C | 46 °C min |
| Flash point | > 300 °C | 230 °C min |
| Ductility at 25 °C | > 100 cm | 100 cm min |
| Solubility in trichloroethylene | 99.8 wt% | 99.0 wt% min |
| TFOT — change in mass | 0.1 wt% | 0.8 wt% max |
| TFOT — retained penetration | 74% | 52% min |
| TFOT — ductility of residue | > 100 cm | 50 cm min |
The other four grades are published as specification bands to ASTM methods. Every shipment carries a batch-specific Certificate of Analysis covering penetration, softening point, ductility, flash point, solubility and loss on heating.
Product specification Penetration-grade paving bitumen, 40/50 to 85/100 Five grades with full test results, the 60/70 thin-film oven test, packaging and trading terms.Shipping to East Africa, India and the GCC
Packaging decides the freight more than the distance does:
- Drums: new steel drums of 150 or 180 kg net, about 20 MT per 20 ft container. Drum weight is confirmed at order stage because it changes the container count.
- Bulk: heated bitutainers or tankers for larger tonnages, where the receiving terminal can hold the binder hot.
- By sea: EXW, FOB, CFR or CIF from Bandar Abbas or Bandar Imam Khomeini to East African, Indian and Gulf ports; other ports by arrangement.
- Overland: DAP or FCA by truck and rail through Iran's land borders.
| Item | Terms |
|---|---|
| Minimum order | 1 × 20 ft container (approx. 20 MT drummed); larger tonnages by bulk vessel or bitutainer; trial quantities available |
| Packaging | New steel drums of 150 kg or 180 kg net, 1 MT poly bags, or bulk in heated bitutainer or tanker |
| Lead time | 7–14 days for standard grades after order confirmation |
| Certification | Batch-specific CoA per shipment; SGS, Bureau Veritas or your own inspector at the buyer's cost; Safety Data Sheet with every consignment |
| HS code (6-digit) | 2713.20 (petroleum bitumen) — national subheadings vary |
Before you order
- Name the standard, not just the grade: ASTM penetration bands, ISIRI 12505 or IS 73 viscosity grading.
- Send the design temperature range and traffic so the grade can be checked against the road, not the price list.
- Ask for the TFOT results on the lot offered, not a typical sheet.
- Store it correctly: drums upright and under cover; bulk below 180 °C; never let water into hot bitumen.
Frequently asked questions
What is the difference between bitumen 60/70 and VG-30?
They are named under different systems. 60/70 is a penetration grade measured at 25 °C; VG-30 is an IS 73 viscosity grade measured at 60 °C. The two overlap but are not interchangeable without testing.
Do you supply VG-30?
Our listed range is five penetration grades. If your tender specifies VG-30, send the specification and we will confirm whether a lot tested to IS 73 can be offered, rather than relabel a penetration grade.
Which grade suits a hot climate with heavy trucks?
40/50, the hardest of the five, resists rutting under heavy axle loads. 60/70 is the usual choice for temperate climates.
How many drums fit in a container?
About 20 MT of drummed bitumen fits a 20 ft container. Drums are 150 or 180 kg net, and the drum weight is confirmed at order stage.
What is the minimum order?
One 20 ft container, approximately 20 MT drummed. Larger tonnages ship by bulk vessel or bitutainer, and trial quantities can be arranged.
Which HS code applies?
2713.20, petroleum bitumen. National subheadings vary by destination.