Bitumen Specific Gravity Laos
Last updated: 2026-10-11
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Bitumen Specific Gravity Laos: Direct Answer
Bitumen specific gravity in Laos typically ranges from 1.01 to 1.05 at 25°C, with the most commonly exported grade (penetration 60/70) averaging 1.03. For a standard 180 kg drum, this equals approximately 174.8 liters of bitumen, while a 20-foot container carrying 24 drums (4.32 MT) occupies about 4,200 liters. These figures matter because every 1% error in specific gravity shifts your freight volume, container weight declaration, and landed cost by roughly $120–$260 per shipment into Vientiane or Savannakhet.
Why Bitumen Specific Gravity Varies in Laos
Bitumen is not a single compound. It is a colloidal blend of asphaltenes, resins, andmaltenes, and its specific gravity depends on three variables:
- Source crude: Middle East crude (Kuwait, Iran) yields bitumen with SG 1.02–1.04; Venezuelan or Canadian heavy crude pushes SG toward 1.04–1.06.
- Penetration grade: Lower penetration (harder) grades have higher SG. 40/50 sits around 1.04; 80/100 sits around 1.01.
- Temperature: SG is temperature-corrected to 25°C. At 150°C (spraying temperature), volume expands ~8%, so SG drops to roughly 0.96.
Laos itself has no commercial crude refining capacity. All bitumen entering the country is imported — primarily from Thailand (Rayong and Sriracha refineries), Vietnam, and Singapore, with re-export flows sometimes originating in Iran or the UAE. This is why "bitumen specific gravity Laos" is really a question about imported grades distributed in Laos, not domestic production.
| Temperature | Volume Change vs 25°C | Effective SG (base 1.03) | Use Case |
|---|---|---|---|
| 25°C | Baseline | 1.030 | Lab testing, documentation |
| 60°C | +2.6% | 1.003 | Storage tank measurement |
| 135°C | +6.8% | 0.963 | Mixing with aggregate |
| 150°C | +8.1% | 0.953 | Spraying / paving |
| 160°C | +9.0% | 0.944 | Hot mix plant discharge |
Key takeaway: Never quote a single SG number without a temperature. Customs and freight forwarders in Laos will reject undeclared temperature references on Form D and shipping manifests.
Bitumen Grades Used in Laos: SG and Specification Comparison
Laos follows TCVN (Vietnamese) and TIS (Thai) standards more often than ASTM, because most supply enters across the Thai–Lao Friendship Bridge or via Vietnam's border at Lao Bao. Below is a working reference table for procurement teams.
| Grade | Standard | SG @ 25°C | Penetration (0.1mm) | Softening Point (°C) | Typical Use in Laos |
|---|---|---|---|---|---|
| 40/50 | ASTM D946 | 1.040–1.045 | 40–50 | 52–58 | Highway base, Vientiane–Pakse |
| 60/70 | ASTM D946 | 1.030–1.035 | 60–70 | 49–56 | National roads, mainstay grade |
| 80/100 | ASTM D946 | 1.010–1.020 | 80–100 | 45–52 | Rural roads, cooler provinces |
| 160/220 | ASTM D946 | 1.000–1.010 | 160–220 | 38–45 | Cold climate patch, Xieng Khouang |
| Pen 60/70 (Iranian) | JIS K2207 | 1.028–1.038 | 60–70 | 50–56 | Container imports via Singapore |
| Pen 60/70 (Thai) | TIS 2686 | 1.030–1.036 | 60–70 | 49–55 | Bulk truck from Rayong |
Practical note: Two suppliers can both sell you "60/70" and quote SG values that differ by 0.008. Over a 5,000 MT order, that difference is 40 MT of declared weight — enough to trigger a customs re-inspection at Thanaleng or Savannakhet.
How to Convert Bitumen Specific Gravity to Volume and Cost (Laos Context)
The conversion is straightforward but unforgiving:
Volume (liters) = Mass (kg) ÷ (SG × 1 kg/L)
At SG 1.03, 1 MT of bitumen = 970.9 liters. At SG 1.04, it equals 961.5 liters. That 1% swing changes a 20-foot container's cargo discharge report.
| Parameter | 60/70 @ SG 1.03 | 40/50 @ SG 1.045 | Delta |
|---|---|---|---|
| Order quantity | 100 MT | 100 MT | — |
| Volume at 25°C | 97,087 L | 95,694 L | -1,393 L |
| Drums (180 kg) | 556 | 556 | — |
| 20-ft containers | 23 | 23 | — |
| CIF Vientiane (est.) | $68,000 | $68,000 | — |
| Landed cost per MT with 7% VAT | $756 | $756 | — |
| Freight surcharge if weight declared at 1.045 | $0 | +$340 | +$340 |
Prices indicative for 2024-25. Actual CIF Lao PDR depends on route: Thai trucking ~$18–$24/MT; Vietnamese trucking via Lao Bao ~$22–$30/MT.
Bottom line: Getting SG right isn't academic. It affects customs duty base, truck axle loads on Route 13, and inbound container weight certification.
Testing Bitumen Specific Gravity in Laos: Methods and Labs
Laos does not host an internationally accredited bitumen testing lab certified to ISO 17025 for SG determination. That means spec sheets usually come from the port of origin — Singapore, Rayong, Haiphong — and are re-verified only by the buyer's team.
The two relevant test methods:
- ASTM D70 — Specific gravity by pycnometer. Most accurate, used for reference testing. Requires ~2 hours per sample.
- ASTM D71 — Specific gravity by displacement. Faster, acceptable for routine QC. Used widely in Thai and Vietnamese labs supplying Laos.
| Location | Lab Type | Turnaround | Cost per Sample |
|---|---|---|---|
| Vientiane | Private QC (limited) | 3–5 days | $45–$90 |
| Nong Khai, Thailand | Accredited | 1–2 days | $60–$110 |
| Bangkok | ISO 17025 | 2–3 days | $120–$200 |
| Haiphong, Vietnam | Accredited | 2–4 days | $70–$130 |
| Singapore (origin test) | ISO 17025 | At loadout | Included in COA |
Actionable advice: For any Lao contract above 200 MT, budget for one independent SG verification at Nong Khai or Bangkok. At $110 per sample, this is the cheapest insurance against a $3,000+ customs weight dispute.
Common Errors When Using Bitumen SG Data for Laos Shipments
- Using SG 1.00 as default. Bitumen is heavier than water. Declaring SG 1.00 understates weight by ~3% and can void your insurance if a tanker or container fails a load check.
- Ignoring temperature at loadout. A tanker loaded at 150°C in Rayong and delivered at 60°C in Vientiane will show a volume increase at destination — not a mass increase. Some buyers mistake this for "shortage."
- Mixing SG standards. TIS reports often use SG at 25/25°C, ASTM at 25/25°C too, but some UAE suppliers report 15.6/15.6°C (60/60°F). A 0.005–0.010 offset is standard between the two.
- Assuming drum tare weight is constant. A 180 kg drum has a tare of 18–22 kg. Over 556 drums, that's a 10–12 MT swing in payload — dwarfing most SG errors.
- Applying SG from COA to a different batch. Bitumen SG drifts ±0.004 batch-to-batch even from the same refinery. Never reuse a COA SG value across shipments without verification.
FAQ: Bitumen Specific Gravity in Laos
What is the specific gravity of bitumen 60/70 in Laos?
Bitumen 60/70 delivered in Laos typically has a specific gravity of 1.030 to 1.035 at 25°C. Thai-origin material (TIS 2686) sits near 1.032, while Iranian-origin 60/70 imported via Singapore averages 1.033. Always confirm against the batch COA.
Does bitumen specific gravity affect customs duty in Laos?
Yes — Lao customs assesses duty and VAT on declared weight, which is derived from volume × SG. A 0.01 SG error on a 500 MT shipment shifts declared mass by 5 MT, changing the duty base by roughly $850–$1,200 under current Lao tariff schedules.
How many liters is 1 MT of bitumen in Laos?
At the standard Lao import SG of 1.03, 1 metric ton equals 970.9 liters at 25°C. At 60/70 grade extremes — SG 1.030 to 1.035 — the range is 966 to 971 liters per MT.
Why is bitumen specific gravity higher than 1.0?
Bitumen is denser than water because of its high concentration of asphaltenes and heavy aromatic resins, which pack more mass per unit volume. Even the lightest paving grades stay above SG 1.00; harder grades like 40/50 reach 1.045.
Which bitumen grade has the highest specific gravity in Laos?
Grade 40/50 has the highest SG among standard Lao imports, averaging 1.040–1.045 at 25°C. Grade 160/220 is the lowest, averaging 1.000–1.010, reflecting its lighter, more paraffinic composition.
Calculate Your Laos Bitumen Landed Cost Accurately
Specific gravity is one number — but it touches freight, duty, container weight, and final CIF in Vientiane. Before you quote your next Lao shipment, run the numbers properly.
Use the 6Tar cost calculator to convert SG, volume, tonnage, and route into a full landed-cost breakdown in under 60 seconds. It factors in Thai and Vietnamese trucking rates, Lao VAT, and container weight surcharges automatically — so you never under-declare SG again.