中国沥青供应 · Bitumen Supply to China

中国道路石油沥青按标号分级，如70号、90号、50号，标号是针入度的名义值而非区间，70号对应针入度60–80。技术要求主要来自交通运输部的JTG F40-2004施工规范和国家标准GB/T 15180。每个标号又分A、B、C三个质量等级，三者针入度相同，区别在蜡含量、低温延度与老化后性能。蜡含量是中东沥青进入中国市场最主要的技术障碍，因为ASTM与EN标准根本不规定这一项。JTG F40-2004是交通运输部的施工技术规范，带A、B、C等级；GB/T 15180是推荐性国家产品标准，采用AH-系列，不设等级。针入度合格只能证明标号，不能证明等级。

Chinese road bitumen is graded by a hash number such as 70#, 90# or 50#, where the number is a nominal penetration rather than a band: 70# accepts penetration 60–80 dmm. The requirements come from two separate documents, the Ministry of Transport construction specification JTG F40-2004 and the national product standard GB/T 15180. Each grade is further divided into quality classes A, B and C, which share the same penetration and are separated by wax content, low-temperature ductility and post-ageing behaviour. Wax content is the single biggest technical barrier for Middle East bitumen entering China, because neither ASTM D946 nor EN 12591 specifies it at all.

Two further points structure everything below. The first is documentary. JTG F40-2004 is a Ministry of Transport construction specification and it is the document that carries the A/B/C classes; GB/T 15180 is a recommended national product standard using the AH- designations, and it carries no class system at all, so a class quoted against it is not a specification. The second is evidential. Because penetration is identical across the three classes and tested identically, a penetration result inside the band is evidence of the grade and no evidence whatever of the class. The lines that evidence a class are wax content, ductility at 10 °C, the penetration index window and the requirements on the residue after ageing — and a certificate that omits them has not demonstrated the thing the project is buying.

A Chinese grade is written as a number followed by a hash: 70#, 90#, 50#. That number is the nominal penetration (针入度), and the acceptance band sits either side of it. So 70# accepts any penetration from 60 to 80 dmm.

An ASTM grade works differently. In 60/70, the two numbers are the band: 60 to 70 dmm, nothing outside it. The band is 10 dmm wide against the Chinese 20.

The consequence is asymmetric and worth stating plainly. A cargo certified as ASTM 60/70 falls entirely inside the 70# band, so on penetration alone it qualifies. A cargo certified as 70# does not necessarily satisfy 60/70, because it may test anywhere up to 80 dmm. Penetration is also only the first line of either specification, so satisfying it settles nothing on its own.

The grades in commercial use

• 50# — penetration 40–60, hot southern regions and heavily loaded corridors
• 70# — penetration 60–80, the mainstream Chinese paving grade
• 90# — penetration 80–100, temperate and northern regions
• 110# — penetration 100–120, cold-region paving and spray work
• 130# — penetration 120–140, severe cold zones and emulsion feedstock

JTG F40 also defines 30# at the hard end, penetration 20–40, for heavy-duty and high-modulus base layers in the hottest conditions, and 160# at the soft end. Neither is common in import trade. This page does not state a band for 160# because it cannot source one to the requirement table, and an omitted figure is correct where an estimated one would not be.

带宽的算术 · The arithmetic of the three conventions

The band widths are worth having in front of you, because the three systems are not merely offset from one another — they are differently shaped, and that is where mis-specification happens.

• The Chinese bands are a uniform 20 dmm wide from 50# to 130#: 40–60, 60–80, 80–100, 100–120, 120–140. 30# is 20 dmm wide as well.
• ASTM D946 bands are not uniform. 40/50 and 60/70 are 10 dmm wide, 85/100 is 15, 120/150 is 30, 200/300 is 100.
• EN 12591 uses a third set again, among them 35/50 (15 wide), 50/70 (20), 70/100 (30), 100/150 (50) and 160/220 (60).

Two practical consequences follow. First, a European 50/70 is the same width as a Chinese band but sits lower: a 50/70 cargo testing at 55 dmm is comfortably inside its own grade and outside 70#, and inside 50# instead. A buyer who treats 50/70 as the European name for 70# will receive material that is legitimately in grade and legitimately out of specification at the same time. Second, a wide European band can straddle two Chinese grades at once: EN 100/150 runs 100 to 150 dmm and so contains the whole of 110# and the whole of 130#. On that part of the series the European grade name cannot select a Chinese number at all, and only the measured value on the batch certificate can.

60/70 投70# 还要证明什么 · What an ASTM certificate still has to prove

Penetration containment is the easy half of offering an ASTM cargo against a Chinese project. A binder built to ASTM D946 60/70 and offered against 70# A级 has five further lines to clear, and its own standard asked for none of them at that level.

• Flash point. JTG F40 sets a floor of 260 °C at 70# by T 0611, where ASTM D946 requires 232 °C. A genuine, fully compliant 60/70 can flash below the Chinese floor and still be exactly what it was sold as.
• Solubility. Minimum 99.5 % by T 0607 against 99.0 % in ASTM D946 — half a point, and a real difference on filler-extended material.
• Ductility. Both documents ask for 100 cm and they ask for it at different temperatures: 15 °C by T 0605 in Chinese practice, 25 °C by ASTM D113. The binder is stiffer at 15 °C and far more likely to fail there, so a 25 °C result is not evidence of the 15 °C line.
• Wax content. By T 0615, with no counterpart anywhere in ASTM D946. This is the line that arrives absent rather than failing.
• The rheological pair. 60 °C dynamic viscosity, minimum 180 Pa·s at 70# A级 by T 0620, and the penetration index window, which is -1.5 to +1.0 at 70# A级. Neither appears on an ASTM paving certificate.

Every one of those is a test that was never ordered rather than a test that was failed, and a test that was never ordered cannot be added to a certificate afterwards. Order them on the batch before the cargo is nominated. Offering 60/70 into China takes the comparison line by line.

标号没有说的事 · What the number does not carry

A Chinese grade number is a single measurement expressed as a name. It carries no quality class, no governing standard, no edition of that standard, no climate zone and no pavement layer. Four of those five decide whether a cargo is accepted, and none of them can be inferred from the number. This is why an enquiry reading we need 5,000 MT of 70# is not yet a technical requirement: it has fixed one line of a table that the specification treats as a set.

合同里该怎么写 · What to write instead of 70#

Write the grade, the standard, the edition and the class as one string, and then reuse that string without paraphrase in the contract, the credit application, the invoice, the certificate of analysis and the customs declaration. Something of the form 70号道路石油沥青 to JTG F40-2004, A级, or where an ASTM cargo is being offered against a Chinese project, Bitumen 60/70 to ASTM D946, supplied against 70号道路石油沥青 to JTG F40-2004, A级. Naming both is not redundancy: it records exactly what is being claimed and against which document, so that a bank comparing an invoice with a credit, and an engineer comparing a certificate with a project specification, are reading the same sentence rather than two paraphrases of it. The grade equivalence chart sets out how the three naming systems line up across the whole series.

Every JTG F40 grade is divided into three quality classes (质量等级): A级, B级 and C级. The critical point is that penetration is identical across all three. You cannot read the class off the grade number, and a certificate showing a perfect penetration result tells you nothing about which class the material qualifies for.

What separates the classes is a different set of properties: wax content, ductility at 10 °C, penetration index and the requirements on the residue after ageing. A级 is permitted for all grades and all pavement layers; the lower classes are restricted to lower highway classes and lower layers.

Commercially this means a cargo can be genuinely good 70#, meet every line a Western buyer would check, and still be refused because the project specified A级 and the material only reaches B级. The class page sets out which properties decide it and what to state in an enquiry.

针入度合格不能证明等级 · A penetration pass is not evidence of a class

This deserves stating as an evidential rule rather than as a caution, because it is the specific reason certificates get sent back. Take a certificate reporting penetration 68 dmm, softening point 48 °C, flash point 265 °C and solubility 99.6 %. Every one of those is a pass against 70# A级. The document has still not evidenced the class, because the class is carried by properties that are not on it.

Sort the lines into three groups and the point becomes mechanical:

• Lines that are identical across the classes. Penetration by T 0604 is the first of them: it selects the grade and does nothing else, so a result of 68 dmm is 70# A级, 70# B级 and 70# C级 at the same time. Three more sit beside it at 70# — ductility at 15 °C, minimum 100 cm by T 0605; flash point, minimum 260 °C by T 0611; and solubility, minimum 99.5 % by T 0607. Those four are the lines an export certificate is most likely to carry, and not one of them discriminates between the classes.
• Lines that move a little with the class. Softening point at 70# is minimum 46 °C for A级, 45 °C for B级 and 43 °C for C级 by T 0606. A result of 48 °C therefore clears all three and discriminates between none of them.
• Lines that carry the class. Wax content by the distillation method T 0615, capped at 2.2 %, 3.0 % and 4.5 %; ductility at 10 °C by T 0605; the penetration index window, which is -1.5 to +1.0 at 70# A级; and the requirements applied to the residue after the rolling thin film oven test or thin film oven test. These are the four the certificate above is silent on.

So the rule for reading an incoming certificate is: count the class-carrying lines, not the passes. A report with ten passing values and no wax result has demonstrated a grade and left a class entirely unproven, and a Chinese project engineer is entitled to say so after the cargo has landed.

等级是许可，不是评价 · The class is a permission, not a rating

The permitted-use provision is written per highway class and per pavement layer rather than as a general quality ranking. A级 carries the widest permission: every grade in the series, every layer, on any class of highway. B级 goes into the lower layers of expressways (高速公路) and class-1 highways (一级公路), and into any layer of a highway below that class. C级 is confined to class-2 highways (二级公路) and below.

Read that way, the question a buyer has to answer before an offer can be prepared is not which class do you have but which layer of which highway class is this binder going into. Those two facts fix the class; the class then fixes which lines the certificate has to carry. An expressway surface course is A级 and nothing else will be approved for it, however good the penetration looks. It follows that a binder which cannot reach A级 is not a failed binder but one with a narrower set of permitted applications: a more paraffinic cargo at 2.8 % wax is incapable of A级 and entirely capable of the lower layers of an expressway or of every layer of a class-2 road. Measure the wax figure before quoting and offer into the class that number actually supports, rather than quoting A级 and letting a destination laboratory find the gap.

Chinese specifications limit wax content (蜡含量) by the distillation method, with maximum limits that tighten by quality class. ASTM D946 and EN 12591 do not specify wax content at all. That single gap is the most consequential difference between the export specification a Middle East supplier normally works to and the one a Chinese buyer is holding.

Wax matters because it reduces adhesion to aggregate and widens temperature susceptibility: the binder softens more readily when hot and turns brittle more readily when cold. Naphthenic crudes produce naturally low-wax bitumen and are the domestic quality benchmark in China. More paraffinic crudes produce higher wax.

限值 · The numbers, and which document sets them

Under JTG F40-2004 the distillation-method limits are 2.2 % for A级, 3.0 % for B级 and 4.5 % for C级, by method T 0615 of JTG E20-2011. They are set by class, so they are the same at 50#, 70#, 90# and every other grade in the series. Under GB/T 15180 the limit for AH-70 is a flat 3.0 % with no class structure behind it, which places AH-70 at the B级 level on this line. The practical reading is direct: a cargo measured at 2.8 % is compliant against GB/T 15180 and cannot be offered as JTG F40 A级, and a cargo measured at 3.4 % fails both.

方法 · The method with no ASTM counterpart

T 0615 is a distillation procedure. The nearest European method is EN 12606. There is no counterpart in ASTM D946 at all, which is why the usual situation is not a failing wax result but an absent one: the export laboratory was never asked to run the test, so the technical data sheet has no line for it. An absent figure is not a pass, and a Chinese buyer reading a certificate with no wax line is reading a certificate that cannot support a class.

The practical consequence for a buyer is simple and worth insisting on: obtain a measured wax content figure on the batch Certificate of Analysis before shipment, by T 0615, or by EN 12606 with the method named on the certificate so the engineer can judge the comparison. A supplier who cannot produce one has not tested for it, and material that is high in wax cannot reach A级 however good its penetration and softening point look. Because the wax fraction travels from the crude through the refinery into the residue, this is a property of the crude slate rather than of refinery diligence, and no amount of process control removes it. The wax content page covers the limits, the test method and how to raise it in an enquiry.

China is largely self-sufficient in bitumen from domestic refining. Imported cargo is not filling a shortage; it serves coastal demand where sea freight beats inland haulage, quality arbitrage where a particular specification is easier to source abroad, and specific project requirements.

Two practical consequences follow. First, price and specification discipline are tight, because a domestic alternative always exists. Second, seasonality matters more than in most markets: construction in the north largely stops through winter and northern ports can freeze, so shipment timing is part of the commercial discussion rather than an afterthought. The ports page covers the regional picture, and the climate zone page covers how the same geography drives grade choice.

There is a third consequence that decides where a cargo can profitably land. An imported parcel competes at the point of discharge, where its advantage is coastal proximity against domestic material that has to be moved from a refinery. That advantage erodes with every inland kilometre, which is why the inland leg belongs in the commercial conversation at the same time as the berth, and why the same tonnage can be competitive in one province and uncompetitive two hundred kilometres behind it.

气候分区代码 · The three-digit climate zone code

JTG F40 assigns every project location a three-part climate zone code (气候分区), written as three digits such as 1-4-1 or 2-2-2. Each digit is drawn from a different climate variable and each is read separately:

• First digit — summer high temperature, from the mean maximum air temperature of the hottest month. 1 is above 30 °C, 2 is 20–30 °C, 3 is below 20 °C.
• Second digit — winter low temperature, from the extreme minimum air temperature. 1 is below -37 °C, 2 is -37 to -21.5 °C, 3 is -21.5 to -9 °C, 4 is above -9 °C.
• Third digit — rainfall, from annual precipitation. 1 is humid above 1000 mm, 2 is moist 500–1000 mm, 3 is semi-arid 250–500 mm, 4 is arid below 250 mm.

Note the direction, because it runs against intuition in the middle position: in every digit, 1 marks the most demanding end of its variable — the hottest summer, the coldest winter, the wettest climate. A second digit of 4 is a mild winter, not a severe one.

代码往哪个标号推 · Which grade each digit pushes toward

The first two digits select the grade between them; the third does not select it at all.

• A leading 1 pushes toward the hard end. Rutting is the governing risk, so the selection moves to 50#, or to the harder half of the 70# band, with 30# considered for heavy-duty and high-modulus base layers. The lines that then decide the cargo are softening point by T 0606 and 60 °C dynamic viscosity by T 0620 — minimum 180 Pa·s at 70# A级 — because 60 °C approximates the temperature of a hot surface layer in service and is a far more direct rutting indicator than penetration measured at 25 °C.
• A second digit of 1 or 2 pushes toward the soft end. Thermal cracking governs, so the selection moves to 90#, 110# and 130#, and the gatekeeping lines become ductility at 10 °C by T 0605, the residue ductility after ageing and the penetration index window rather than anything at the high-temperature end.
• Both at once cannot be solved along the penetration series. A site with hot summers and winter minima below -21.5 °C demands high-temperature stiffness and low-temperature flexibility of the same binder. That is the combination where 改性沥青 — modified binder — becomes necessary rather than preferable, and where an unmodified grade of any number is the wrong answer.
• The third digit changes the mix, not the grade. No amount of rain turns 70# into 90#. A humid zone drives binder–aggregate adhesion provisions, anti-stripping treatment and mixture water sensitivity testing, and a semi-arid or arid zone shifts the weight onto oxidative ageing and the diurnal temperature swing, which means the ageing residue block and the penetration index carry more of the decision.

代码属于工点，不属于城市 · The code belongs to the site

Two cautions before the code is used commercially. It is a property of the project location rather than of the nearest city: elevation, terrain and distance from the coast move it within a short distance, which is why this site describes regional climate qualitatively and does not assign codes to provinces. And the grade selection itself belongs to the project design, applying the selection provisions of the edition of JTG F40 named in the tender together with traffic loading, highway class and pavement layer. A supplier's job is to establish which grade and class the project has selected and prove the binder against it line by line — not to select on the project's behalf. Ask for the code as it appears in the project documents, and quote it back in the offer in the same form.