Bitumen 60/70 and 80/100 describe penetration ranges, not two levels of product quality. The useful buying question is not “Which number is better?” but “Which material satisfies the approved specification for this project?” Start with that requirement before comparing suppliers or requesting a shipment price.
What do the grade numbers mean?
In penetration grading, a standardized needle test measures consistency under stated test conditions. The commercial designations 60/70 and 80/100 refer to different penetration ranges, conventionally expressed in tenths of a millimetre. A higher penetration generally indicates a softer binder under those test conditions. It does not, by itself, describe every aspect of road performance.
Compare requirements, not just grade names
Ask the project engineer for the applicable specification and its edition. Record the required tests, acceptance limits and whether the project allows a penetration grade at all. If a tender calls for a viscosity grade or performance grade, do not assume that a familiar penetration grade is an automatic substitute.
Climate, traffic, aggregates and the approved asphalt mix all belong in the technical evaluation. A supplier's general statement about suitability for “hot weather” is not a replacement for a project-specific approval. Likewise, sharing part of a penetration range does not make two grades under different standards interchangeable.
What should you ask a supplier for?
- The complete proposed specification, including test methods and units.
- A current technical data sheet for the actual offered product.
- A representative COA clearly labelled as a sample, followed by the shipment batch report when available.
- The proposed origin, packing format, net quantity and delivery basis.
- Written clarification of any deviation from the purchase specification.
Do not compare a guaranteed contract limit with another supplier's typical value as if they were the same promise. Put the agreed limits into the purchase documents, and identify who reviews and approves the laboratory results before dispatch.
Build a clearer quotation request
A useful enquiry might say: “Please quote the project-approved penetration grade against the attached specification, for the stated net tonnage, packing format and named destination port. Confirm document availability, inspection arrangements and the proposed shipment window.” This makes the offer easier to evaluate than a message asking only for the “best price for bitumen”.
Keep commercial and technical approval separate. A competitive quotation is not evidence that the offered product has met the project requirements. Resolve missing test data or deviations before treating two offers as equivalent.
