空调风管一吹热风就析出，出风口一股怪味。低气味没选对，风管就是污染源。
一句话结论：空调风管，低气味是硬门槛
空调风管直接对着乘客吹气，气味是头一条红线。
TPE 做风管，低气味、耐温、可挤出成型是三个硬指标——结论先给：乘员舱空调风管用低气味 SEBS 基 TPE；耐温苛刻段（靠近机舱），
TPV 或复合结构优先。
空调风管的投诉多是气味：吹出来的风有塑料味，乘客投诉、车企召回。气味等级（按车企标准）写进验收——气味不过，整批退回。
认证不齐，出不了口：出口空调风管要过材料认证（如欧盟、北美标准）。认证周期长，提前规划——别等订单来了才补证。
为什么 TPE：低气味加可成型
空调风管用 TPE 的理由：低气味配方、挤出成型效率高、耐温够用、可回收——四条合起来，适合空调风管。
低气味不是靠香精遮，是靠源头树脂加脱挥——油品等级、助剂、脱挥工艺三样决定气味，VOC 和气味等级按车企标准验。
耐温要看位置：空调风管靠近机舱段温度高。按段选料或复合——一段一料，别一刀切。
工况拆解：气流、温度、凝露
气流工况：长期吹风，材料表面要稳定——析出物会随气流进车厢，析出测试别漏。
温度工况：夏天制冷管道温度低、靠近机舱段温度高。冷热两头验——凝露水长期泡着，耐水要验。
凝露工况：制冷段常年凝露，水汽长期接触。耐水解、不发霉——水汽场景，材料不能软塌。
对比表：TPE vs PP 做空调风管
| 维度 | TPE | PP |
|---|
| 气味 | 低气味可做 | 需助剂控制 |
| 柔软度 | 好 | 硬 |
| 密封性 | 好（弹性） | 需密封结构 |
| 耐温 | 100℃+ | 100℃+ |
| 成本 | 中高 | 低 |
| 回收 | 可回收 | 可回收 |
表格读法：PP 便宜但硬、密封要结构补；TPE 弹性密封好、气味可控——要密封和低气味的段位，TPE 有优势。
风管结构常是复合：骨架 PP 加密封 TPE。复合材料，各用所长——别指望一种料解决所有问题。
常见坑：气味报告过时和剥离不牢
坑一：气味报告过时。配方一改，气味等级就变——报告要跟配方同步，别拿旧报告撑门面。
坑二：复合风管剥离不牢。PP 骨架和 TPE 密封层剥离力不够，用久分层——剥离力测试（按标准）写进验收。
坑三：忽略析出。风管内壁析出，白粉吹进车厢——析出测试，和气味一样重要。
空调风管到货三笔账，气味等级必测
三问：气味按什么标准、剥离力多少、认证齐不齐。一验：按实际气流打样吹风验证——三问一验，供应商底细清楚。
气味测试要按车企标准：不同车企标准不同（如气味等级 1-6 级）。按客户标准测——标准对齐，报告才有效。
留样要成习惯：每批留样，气味和剥离按批次复测。批次换料先对比再放量——批次稳，客诉少。
延伸判断：空调风管的析出测试，别只测气味
风管内壁析出白粉，随风吹进车厢就是投诉——高温烘箱析出测试和气味一样重要，别只测气味不测析出。
析出测试要按气流场景：风管内壁析出，随风吹出。按实际风道条件测——场景对齐，数据才可信。
风管漏风漏味先查卡箍和密封圈，别先怪料——接头配合不对，密封再好也漏，结构是看不见的漏点。
耐凝露要单独测：制冷段常年凝露。耐水解、不发霉——凝露场景，别漏。
空调风管的成本账，算总账：单价、气味投诉、返工、召回。气味投诉伤品牌——总账算清，贵料不贵。
供应商问四句：什么体系、气味按什么标准、认证齐不齐、变更会不会通知。四句问完，底细清楚——问对问题，比压价有用。
空调风管的密封结构，一起设计
空调风管的密封结构，一起设计：风管与接头、风管的卡箍配合。结构配合对了，密封才稳——材料与结构，两头都要对。
空调风管的追溯，写进合同
风管析出白粉，先查批次追溯——批次、原料、生产日期写进合同，三证不齐出口就卡关。
空调风管的合规，按三证查：气味报告、认证文件、批次数据。三证齐全，出口才不卡关。
| 气味等级（1-6 级） | 说明 | 应用 |
|---|
| 1-2 级 | 几乎无味 | 高端车型 |
| 3 级 | 轻微、可接受 | 主流车型 |
| 4 级 | 明显 | 低端/非内饰 |
| 5-6 级 | 强烈 | 不适用内饰 |
表2读法：气味等级是车企验收的硬指标。等级对不上，整批退回——先对齐等级，再谈价格。
| 风管段位 | 温度 | 材料建议 |
|---|
| 出风口段 | 常温 | SEBS 基低气味 |
| 中间段 | 60-80℃ | SEBS/TPO |
| 机舱过渡段 | 100℃+ | TPV |
| 接头密封段 | 按环境 | 弹性密封体系 |
表3读法：风管分段选料，一段一料。别指望一种材料通吃全管。
科隆客户案例：成品异味被退回，匹配基材良率98%
台州一家汽车零部件厂，空调风管成品异味被下游退回，货压在仓库。科隆配合重新匹配包胶基材与加工温度，异味消除，量产良率稳定在 98%。异味是基材和温度的匹配问题——匹配对了，气味自然合格。
小结
如果你正卡在汽车空调风管的选型上，把工况发过来，我们对一遍，收藏起来备查。
As soon as the air conditioner duct blows hot air, it precipitates, and the air outlet emits a strange smell. If the low-odor option is not chosen correctly, the duct itself becomes a source of pollution.
One-sentence conclusion: For air conditioning ducts, low odor is a strict requirement.
The air conditioner vents blow directly at the passengers, and the smell is the first red flag.
TPE for air ducts: low odor, temperature resistance, and extrudability are three hard requirements — here’s the conclusion first: for the passenger cabin air conditioning ducts, use low-odor SEBS-based TPE; for sections with strict temperature requirements (near the engine compartment),
TPV or composite structures are preferred.
Most complaints about air conditioning ducts are about the smell: the air blowing out has a plastic odor, passengers complain, and car companies issue recalls. The odor level (according to the car company's standards) is written into the inspection acceptance—if the smell doesn't pass, the whole batch is returned.
Incomplete certification, can't be exported: Export air conditioner ducts need to pass material certification (such as EU and North American standards). Certification takes a long time, plan in advance—don't wait until orders come to complete the certification.
Why TPE: low odor and moldable
Reasons for using TPE in air conditioning ducts: low-odor formula, high extrusion efficiency, adequate temperature resistance, recyclable—combined, these four make it suitable for air conditioning ducts.
Low odor is not masked by fragrance; it relies on source resin plus degassing — the odor is determined by three factors: oil grade, additives, and degassing process. VOC and odor levels are tested according to automaker standards.
Temperature resistance depends on the location: the air conditioning ducts near the cabin section have high temperatures. Choose materials by section or composite—one material per section, don't use a one-size-fits-all approach.
Operating Condition Breakdown: Airflow, Temperature, Condensation
Airflow conditions: long-term blowing, the material surface must be stable — precipitates can enter the cabin with the airflow, and precipitation tests should not be missed.
Temperature conditions: In summer, the temperature of the cooling pipeline is low, while the temperature near the engine compartment section is high. Check both hot and cold ends — condensation water remains for a long time, so water resistance needs to be tested.
Dew Condensation Condition: The refrigeration section experiences year-round dew condensation, with long-term exposure to water vapor. Hydrolysis-resistant and mold-free—the material must not collapse in water vapor environments.
Comparison Table: TPE vs PP for Air Conditioning Ducts
| Dimension | TPE | PP |
|---|
| smell | Low odor, can be done | Requires additive control |
| Softness | Good | hard |
| Sealing performance | Good (flexible) | Requires a sealed structure |
| Temperature resistant | 100℃ | 100℃ |
| Cost | Medium-high | Low |
| Recycle | Recyclable | Recyclable |
Table reading: PP is cheap but hard, and sealing requires structural reinforcement; TPE has good elastic sealing and controllable odor — for levels requiring sealing and low odor, TPE has an advantage.
Duct structures are often composite: a PP frame with TPE sealing. Composite materials, each used for their strengths—don’t expect one material to solve all problems.
Common pitfalls: outdated odor reports and poor adhesion
Pitfall 1: Outdated odor report. Once the formula changes, the odor level changes too — the report must be updated in sync with the formula; don't use an old report to show off.
Pitfall 2: Composite air duct delamination is not secure. The PP skeleton and TPE sealing layer have insufficient adhesion, leading to delamination over time — perform peel strength tests (according to standards) and include the results in the inspection acceptance.
Pitfall Three: Ignoring deposition. Deposits on the inner wall of the air duct, white powder blown into the cabin — deposition testing is as important as odor.
Three records for air conditioning duct deliveries, odor level must be tested
Three questions: What standard is used for the odor, how much peeling force, and whether the certification is complete. One test: Verify by blowing air according to the actual airflow—three questions and one test make the supplier's details clear.
Odor testing must follow the automaker's standards: different automakers have different standards (such as odor levels 1-6). Testing according to the customer's standards—only when the standards are aligned is the report valid.
Making sample retention a habit: Retain samples of each batch, and re-test the odor and separation by batch. When changing material for a batch, compare first before scaling up — stable batches lead to fewer customer complaints.
Extended judgment: For the air conditioning duct precipitation test, don't just measure the odor
White powder deposits on the inner wall of the air duct, and when blown into the cabin with the wind, it leads to complaints — high-temperature oven deposition testing is just as important as odor testing, so don't just test for odor and neglect deposition.
Precipitation testing should follow the airflow scenario: precipitation occurs on the inner wall of the duct and is blown out with the wind. Measurements should be taken according to the actual duct conditions—only when the scenario aligns will the data be reliable.
If the air duct is leaking air or odor, first check the clamps and seals. Don't blame the material first—if the joints don't fit properly, even the best seal will leak. The structure is an invisible source of leaks.
Anti-condensation gel needs to be tested separately: condensation occurs year-round in the refrigeration section. Hydrolysis-resistant and mold-proof — in condensation scenarios, don’t miss it.
The cost account of the air conditioning ducts, calculate the general ledger: unit price, odor complaints, rework, recall. Odor complaints damage the brand—calculate the general ledger clearly, expensive materials are not costly.
The supplier asks four questions: What system, according to what standard is the odor, are all certifications complete, and will there be notification of changes. After these four questions, the details are clear—asking the right questions is more useful than squeezing the price.
Design the sealing structure of the air conditioning duct together
The sealing structure of the air conditioning duct should be designed together: the duct and its joints, and the duct's clamping cooperation. Only when the structures fit together properly will the seal be stable—both the materials and the structures need to be correct.
Traceability of air conditioning ducts, written into the contract
White powder appears on the air ducts; first check the batch for traceability—batch number, raw materials, and production date should be included in the contract. Without the three certificates, exports will be blocked.
The compliance of air conditioning ducts is checked according to the three certificates: odor report, certification documents, and batch data. Only when all three are complete can exports proceed smoothly.
| Odor Level (1-6) | Explanation | Application |
|---|
| Level 1-2 | Almost tasteless | high-end models |
| Level 3 | Slight, acceptable | mainstream models |
| Level 4 | Obvious | Low-end/Non-interior |
| Level 5-6 | Strong | Interior not applicable |
Table 2 Reading: The odor level is a strict criterion for automaker acceptance. If the level doesn't match, the entire batch is returned — first align the level, then discuss the price.
| Duct section | Temperature | Material Recommendation |
|---|
| air outlet section | room temperature | SEBS low odor |
| Middle section | 60-80℃ | SEBS/TPO |
| cabin transition section | 100℃ | TPV |
| Joint sealing section | According to the environment | Flexible sealing system |
Table 3 Reading: Select materials for each section of the duct, one material per section. Don’t expect one material to work for the entire duct.
Cologne Customer Case: Finished Product Odor Returned, Substrate Matching Yield 98%
A car parts factory in Taizhou had finished air conditioning ducts returned by downstream clients due to odor, with goods piled up in the warehouse. Cologne assisted in rematching the rubber-coated substrate and processing temperature, eliminating the odor, with mass production yield stabilizing at 98%. The odor was a matching issue between the substrate and temperature—once matched correctly, the smell naturally met the standard.
Summary
If you are stuck on selecting air conditioning ducts for cars, send over the working conditions, and we will review it; save it for reference.
