{"product_id":"φ305mm-12in-diesel-vehicle-scr-asc-filter","title":"φ305mm\/12in Diesel vehicle SCR\/ASC filter","description":"\u003cstyle\u003e\n  .cat-faq-module {\n    max-width: 100%;\n    margin: 30px 0;\n    font-family: 'Segoe UI', Roboto, Arial, sans-serif;\n    background: #ffffff;\n    border-radius: 28px;\n    box-shadow: 0 8px 30px rgba(0, 0, 0, 0.06);\n    border: 1px solid #edf2f7;\n    padding: 30px 32px 10px 32px;\n    box-sizing: border-box;\n  }\n  .cat-faq-module .module-header {\n    display: flex;\n    align-items: center;\n    gap: 14px;\n    padding-bottom: 18px;\n    border-bottom: 3px solid #f0f4fa;\n    margin-bottom: 20px;\n  }\n  .cat-faq-module .module-header h2 {\n    font-size: 28px;\n    font-weight: 700;\n    color: #0b1a33;\n    margin: 0;\n    letter-spacing: -0.3px;\n  }\n  .cat-faq-module .module-header .badge {\n    background: #0b1a33;\n    color: #fff;\n    font-size: 14px;\n    font-weight: 600;\n    padding: 2px 18px;\n    border-radius: 30px;\n    letter-spacing: 0.3px;\n  }\n  .cat-faq-module details {\n    display: block;\n    margin-bottom: 6px;\n    border-bottom: 1px solid #eef2f6;\n    padding: 8px 0;\n    transition: all 0.2s ease;\n  }\n  .cat-faq-module details:last-of-type {\n    border-bottom: none;\n  }\n  .cat-faq-module summary {\n    display: flex;\n    align-items: center;\n    cursor: pointer;\n    font-size: 17px;\n    font-weight: 600;\n    color: #0b1a33;\n    padding: 10px 4px 10px 0;\n    list-style: none;\n    position: relative;\n    user-select: none;\n    gap: 12px;\n  }\n  .cat-faq-module summary::-webkit-details-marker {\n    display: none;\n  }\n  .cat-faq-module summary::before {\n    content: \"▶\";\n    font-size: 14px;\n    color: #1a73e8;\n    transition: transform 0.25s ease;\n    display: inline-block;\n    width: 20px;\n    font-weight: 400;\n  }\n  .cat-faq-module details[open] \u003e summary::before {\n    transform: rotate(90deg);\n  }\n  .cat-faq-module summary .q-mark {\n    background: #eef5ff;\n    color: #1a73e8;\n    font-weight: 700;\n    font-size: 14px;\n    padding: 0 12px;\n    border-radius: 20px;\n    line-height: 26px;\n  }\n  .cat-faq-module .answer-wrap {\n    padding: 8px 20px 16px 36px;\n    color: #2c3e50;\n    font-size: 15.5px;\n    line-height: 1.75;\n  }\n  .cat-faq-module .answer-wrap p {\n    margin: 0 0 12px 0;\n  }\n  .cat-faq-module .answer-wrap p:last-child {\n    margin-bottom: 0;\n  }\n  .cat-faq-module .answer-wrap ul, \n  .cat-faq-module .answer-wrap ol {\n    padding-left: 22px;\n    margin: 6px 0 12px 0;\n  }\n  .cat-faq-module .answer-wrap li {\n    margin-bottom: 4px;\n  }\n  .cat-faq-module .answer-wrap strong {\n    color: #0b1a33;\n  }\n  .cat-faq-module .warning-box {\n    background: #f9fcff;\n    border-left: 5px solid #1a73e8;\n    padding: 14px 22px;\n    border-radius: 12px;\n    margin: 12px 0 4px 0;\n    font-size: 15px;\n  }\n  .cat-faq-module table {\n    width: 100%;\n    border-collapse: collapse;\n    font-size: 14.5px;\n    margin: 12px 0;\n  }\n  .cat-faq-module table th,\n  .cat-faq-module table td {\n    border: 1px solid #dce1e9;\n    padding: 8px 6px;\n    text-align: left;\n    vertical-align: middle;\n  }\n  .cat-faq-module table th {\n    background: #f0f4fa;\n  }\n  .cat-faq-module .contact-item {\n    margin-bottom: 10px;\n    padding-left: 4px;\n  }\n  .cat-faq-module .contact-item strong {\n    display: inline-block;\n    min-width: 60px;\n  }\n  @media (max-width: 640px) {\n    .cat-faq-module { padding: 18px 16px 6px 16px; }\n    .cat-faq-module .module-header h2 { font-size: 22px; }\n    .cat-faq-module summary { font-size: 15px; }\n    .cat-faq-module .answer-wrap { padding: 6px 8px 12px 20px; font-size: 14.5px; }\n    .cat-faq-module table { font-size: 12px; }\n    .cat-faq-module table th, .cat-faq-module table td { padding: 4px 3px; }\n  }\n\u003c\/style\u003e\n\n\u003cdiv class=\"cat-faq-module\"\u003e\n  \u003cdiv class=\"module-header\"\u003e\n    \u003ch2\u003e Product Description \u003c\/h2\u003e\n    \u003cspan class=\"badge\"\u003eClick to expand\u003c\/span\u003e\n  \u003c\/div\u003e\n\n  \u003c!-- Q1 – 什么是柴油车SCR\/ASC？ --\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003e\u003cspan class=\"q-mark\"\u003eQ1\u003c\/span\u003e What is a diesel SCR\/ASC system?\u003c\/summary\u003e\n    \u003cdiv class=\"answer-wrap\"\u003e\n      \u003cp\u003e\u003cstrong\u003eSCR (Selective Catalytic Reduction)\u003c\/strong\u003e is an exhaust after‑treatment system that reduces nitrogen oxide (NO\u003csub\u003ex\u003c\/sub\u003e) emissions by injecting urea (AdBlue\/DEF) into the exhaust stream, which decomposes into ammonia (NH₃) and reacts with NO\u003csub\u003ex\u003c\/sub\u003e over a catalyst to produce harmless nitrogen (N₂) and water (H₂O).\u003c\/p\u003e\n      \u003cp\u003e\u003cstrong\u003eASC (Ammonia Slip Catalyst)\u003c\/strong\u003e is a secondary catalyst installed downstream of the SCR. Its sole purpose is to oxidise any excess ammonia that passes through the SCR, preventing it from being released into the atmosphere.\u003c\/p\u003e\n      \u003cp\u003eTogether, the SCR + ASC system:\u003c\/p\u003e\n      \u003cul\u003e\n        \u003cli\u003eReduces NO\u003csub\u003ex\u003c\/sub\u003e emissions by over 95%\u003c\/li\u003e\n        \u003cli\u003eEliminates ammonia slip, ensuring no pungent smell or environmental damage\u003c\/li\u003e\n        \u003cli\u003eMeets Euro 6d and EPA emission standards\u003c\/li\u003e\n      \u003c\/ul\u003e\n      \u003cp\u003eThe ASC is typically a 2‑inch coated substrate containing precious metals (platinum, palladium) that selectively oxidise NH₃ to N₂ and H₂O.\u003c\/p\u003e\n    \u003c\/div\u003e\n  \u003c\/details\u003e\n\n  \u003c!-- Q2 – SCR\/ASC涂钒\/铜\/铁分子筛的区别？ --\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003e\u003cspan class=\"q-mark\"\u003eQ2\u003c\/span\u003e Difference between vanadium, copper‑zeolite, and iron‑zeolite SCR\/ASC coatings?\u003c\/summary\u003e\n    \u003cdiv class=\"answer-wrap\"\u003e\n      \u003cp\u003eSCR catalysts are classified by the active metal used in the coating. The three main types are \u003cstrong\u003evanadium‑based\u003c\/strong\u003e, \u003cstrong\u003ecopper‑zeolite (Cu‑zeolite)\u003c\/strong\u003e, and \u003cstrong\u003eiron‑zeolite (Fe‑zeolite)\u003c\/strong\u003e. Each has distinct characteristics:\u003c\/p\u003e\n      \u003ctable\u003e\n        \u003cthead\u003e\n          \u003ctr\u003e\n            \u003cth\u003eProperty\u003c\/th\u003e\n            \u003cth\u003eVanadium‑based\u003c\/th\u003e\n            \u003cth\u003eCopper‑Zeolite (Cu)\u003c\/th\u003e\n            \u003cth\u003eIron‑Zeolite (Fe)\u003c\/th\u003e\n          \u003c\/tr\u003e\n        \u003c\/thead\u003e\n        \u003ctbody\u003e\n          \u003ctr\u003e\n            \u003ctd\u003e\u003cstrong\u003eActive metal\u003c\/strong\u003e\u003c\/td\u003e\n            \u003ctd\u003eVanadium pentoxide (V₂O₅)\u003c\/td\u003e\n            \u003ctd\u003eCopper (Cu) exchanged in zeolite\u003c\/td\u003e\n            \u003ctd\u003eIron (Fe) exchanged in zeolite\u003c\/td\u003e\n          \u003c\/tr\u003e\n          \u003ctr\u003e\n            \u003ctd\u003e\u003cstrong\u003eOperating temperature range\u003c\/strong\u003e\u003c\/td\u003e\n            \u003ctd\u003e250°C – 450°C\u003c\/td\u003e\n            \u003ctd\u003e180°C – 500°C\u003c\/td\u003e\n            \u003ctd\u003e250°C – 600°C\u003c\/td\u003e\n          \u003c\/tr\u003e\n          \u003ctr\u003e\n            \u003ctd\u003e\u003cstrong\u003eLow‑temperature activity\u003c\/strong\u003e\u003c\/td\u003e\n            \u003ctd\u003eModerate\u003c\/td\u003e\n            \u003ctd\u003eExcellent (active below 200°C)\u003c\/td\u003e\n            \u003ctd\u003eModerate\u003c\/td\u003e\n          \u003c\/tr\u003e\n          \u003ctr\u003e\n            \u003ctd\u003e\u003cstrong\u003eHigh‑temperature durability\u003c\/strong\u003e\u003c\/td\u003e\n            \u003ctd\u003eLimited above 450°C\u003c\/td\u003e\n            \u003ctd\u003eGood up to 650°C\u003c\/td\u003e\n            \u003ctd\u003eExcellent up to 700°C\u003c\/td\u003e\n          \u003c\/tr\u003e\n          \u003ctr\u003e\n            \u003ctd\u003e\u003cstrong\u003eSulfur tolerance\u003c\/strong\u003e\u003c\/td\u003e\n            \u003ctd\u003eGood\u003c\/td\u003e\n            \u003ctd\u003eModerate (sulfur‑sensitive)\u003c\/td\u003e\n            \u003ctd\u003eGood\u003c\/td\u003e\n          \u003c\/tr\u003e\n          \u003ctr\u003e\n            \u003ctd\u003e\u003cstrong\u003eHydrothermal ageing\u003c\/strong\u003e\u003c\/td\u003e\n            \u003ctd\u003eSusceptible at high temp\u003c\/td\u003e\n            \u003ctd\u003eGood durability\u003c\/td\u003e\n            \u003ctd\u003eExcellent durability\u003c\/td\u003e\n          \u003c\/tr\u003e\n          \u003ctr\u003e\n            \u003ctd\u003e\u003cstrong\u003eCost\u003c\/strong\u003e\u003c\/td\u003e\n            \u003ctd\u003eLow\u003c\/td\u003e\n            \u003ctd\u003eMedium\u003c\/td\u003e\n            \u003ctd\u003eMedium‑High\u003c\/td\u003e\n          \u003c\/tr\u003e\n          \u003ctr\u003e\n            \u003ctd\u003e\u003cstrong\u003eTypical application\u003c\/strong\u003e\u003c\/td\u003e\n            \u003ctd\u003eOlder Euro 4\/5 systems\u003c\/td\u003e\n            \u003ctd\u003eEuro 6 light‑duty and heavy‑duty\u003c\/td\u003e\n            \u003ctd\u003eEuro 6 heavy‑duty, high‑load applications\u003c\/td\u003e\n          \u003c\/tr\u003e\n        \u003c\/tbody\u003e\n      \u003c\/table\u003e\n      \u003cp\u003eFor ASC coatings, platinum (Pt) or palladium (Pd) is typically used to oxidise NH₃, with formulations optimised for high selectivity toward N₂ rather than N₂O.\u003c\/p\u003e\n    \u003c\/div\u003e\n  \u003c\/details\u003e\n\n  \u003c!-- Q3 – SCR\/ASC的工作原理？ --\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003e\u003cspan class=\"q-mark\"\u003eQ3\u003c\/span\u003e Working principle of SCR\/ASC\u003c\/summary\u003e\n    \u003cdiv class=\"answer-wrap\"\u003e\n      \u003cp\u003eThe SCR\/ASC system operates through two sequential stages:\u003c\/p\u003e\n      \u003cp\u003e\u003cstrong\u003eStage 1 – SCR (NO\u003csub\u003ex\u003c\/sub\u003e reduction):\u003c\/strong\u003e\u003c\/p\u003e\n      \u003cul\u003e\n        \u003cli\u003eUrea (AdBlue\/DEF) is injected upstream of the SCR catalyst.\u003c\/li\u003e\n        \u003cli\u003eExhaust heat decomposes urea into ammonia (NH₃) and CO₂: CO(NH₂)₂ + H₂O → 2 NH₃ + CO₂\u003c\/li\u003e\n        \u003cli\u003eNH₃ reacts with NO\u003csub\u003ex\u003c\/sub\u003e (NO + NO₂) over the SCR catalyst (Cu‑zeolite, Fe‑zeolite, or vanadium):\u003c\/li\u003e\n        \u003cul\u003e\n          \u003cli\u003e\n\u003cstrong\u003eStandard SCR:\u003c\/strong\u003e 4 NO + 4 NH₃ + O₂ → 4 N₂ + 6 H₂O\u003c\/li\u003e\n          \u003cli\u003e\n\u003cstrong\u003eFast SCR:\u003c\/strong\u003e NO + NO₂ + 2 NH₃ → 2 N₂ + 3 H₂O\u003c\/li\u003e\n        \u003c\/ul\u003e\n        \u003cli\u003eThis achieves up to 95‑98% NO\u003csub\u003ex\u003c\/sub\u003e conversion under optimal conditions.\u003c\/li\u003e\n      \u003c\/ul\u003e\n      \u003cp\u003e\u003cstrong\u003eStage 2 – ASC (Ammonia slip control):\u003c\/strong\u003e\u003c\/p\u003e\n      \u003cul\u003e\n        \u003cli\u003eAny NH₃ that passes through the SCR unreacted enters the downstream ASC.\u003c\/li\u003e\n        \u003cli\u003eThe ASC (coated with Pt\/Pd) selectively oxidises NH₃:\u003c\/li\u003e\n        \u003cul\u003e\n          \u003cli\u003e\n\u003cstrong\u003eDesired reaction:\u003c\/strong\u003e 4 NH₃ + 3 O₂ → 2 N₂ + 6 H₂O\u003c\/li\u003e\n          \u003cli\u003e\n\u003cstrong\u003eAvoided reaction:\u003c\/strong\u003e 2 NH₃ + 2 O₂ → N₂O + 3 H₂O (produces greenhouse gas)\u003c\/li\u003e\n        \u003c\/ul\u003e\n        \u003cli\u003eHigh‑quality ASC ensures that \u0026gt; 90% of slip NH₃ is converted to N₂, eliminating odour and meeting emission limits.\u003c\/li\u003e\n      \u003c\/ul\u003e\n      \u003cp\u003eNO\u003csub\u003ex\u003c\/sub\u003e sensors before and after the SCR, and NH₃ sensors (or virtual sensing) after the ASC, enable closed‑loop control of urea dosing.\u003c\/p\u003e\n    \u003c\/div\u003e\n  \u003c\/details\u003e\n\n  \u003c!-- Q4 – 链接产品CPSI？ --\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003e\u003cspan class=\"q-mark\"\u003eQ4\u003c\/span\u003e What is the cell density (CPSI) of this product?\u003c\/summary\u003e\n    \u003cdiv class=\"answer-wrap\"\u003e\n      \u003cp\u003eOur SCR catalyst features a cell density of \u003cstrong\u003e400 CPSI\u003c\/strong\u003e (cells per square inch).\u003c\/p\u003e\n      \u003cp\u003e\u003cstrong\u003eWhy 400 CPSI is optimal:\u003c\/strong\u003e\u003c\/p\u003e\n      \u003cul\u003e\n        \u003cli\u003e\n\u003cstrong\u003eBalanced flow and efficiency:\u003c\/strong\u003e Provides a high geometric surface area for catalytic reactions while maintaining low exhaust backpressure.\u003c\/li\u003e\n        \u003cli\u003e\n\u003cstrong\u003eDurability:\u003c\/strong\u003e Thick enough cell walls to withstand thermal cycling and mechanical stress, yet thin enough for efficient gas diffusion.\u003c\/li\u003e\n        \u003cli\u003e\n\u003cstrong\u003eCoating retention:\u003c\/strong\u003e Ensures the SCR washcoat (Cu‑zeolite) adheres well and remains stable under high‑temperature operation.\u003c\/li\u003e\n        \u003cli\u003e\n\u003cstrong\u003eIndustry standard:\u003c\/strong\u003e 400 CPSI is the most common specification for heavy‑duty and light‑duty SCR applications.\u003c\/li\u003e\n      \u003c\/ul\u003e\n      \u003cp\u003eIf you require a different cell density for a specific application, please contact our technical team for custom solutions.\u003c\/p\u003e\n    \u003c\/div\u003e\n  \u003c\/details\u003e\n\n  \u003c!-- Q5 – 是否可以批量采购？ --\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003e\u003cspan class=\"q-mark\"\u003eQ5\u003c\/span\u003e Can I place bulk orders?\u003c\/summary\u003e\n    \u003cdiv class=\"answer-wrap\"\u003e\n      \u003cp\u003e\u003cstrong\u003eYes, we support bulk purchasing.\u003c\/strong\u003e\u003c\/p\u003e\n      \u003cp\u003eWe welcome both small‑volume and large‑volume orders. Our production capacity is scalable to meet your demand, whether you are a workshop, a fleet operator, or a distributor.\u003c\/p\u003e\n      \u003cp\u003eFor bulk orders, we offer:\u003c\/p\u003e\n      \u003cul\u003e\n        \u003cli\u003eCompetitive volume pricing\u003c\/li\u003e\n        \u003cli\u003eFlexible lead times\u003c\/li\u003e\n        \u003cli\u003eConsistent quality across batches\u003c\/li\u003e\n        \u003cli\u003eCustom packaging options\u003c\/li\u003e\n      \u003c\/ul\u003e\n      \u003cp\u003ePlease \u003cstrong\u003econtact our customer service team\u003c\/strong\u003e with your required quantity, product specifications, and delivery timeline. We will provide you with a tailored quotation and production schedule.\u003c\/p\u003e\n    \u003c\/div\u003e\n  \u003c\/details\u003e\n\n  \u003c!-- Q6 – ASC氨逃逸催化器专属痛点 --\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003e\u003cspan class=\"q-mark\"\u003eQ6\u003c\/span\u003e What are the specific pain points of ASC (Ammonia Slip Catalyst)?\u003c\/summary\u003e\n    \u003cdiv class=\"answer-wrap\"\u003e\n      \u003cp\u003eThe ASC is installed downstream of the SCR. Its core function is to decompose excess ammonia that escapes from the SCR. When the ASC fails or degrades, the following issues arise:\u003c\/p\u003e\n      \u003cul\u003e\n        \u003cli\u003e\n\u003cstrong\u003e1. Pungent ammonia smell from the exhaust:\u003c\/strong\u003e\u003cbr\u003e\n        Excessive urea injection, SCR ageing, or reduced SCR conversion efficiency allows NH₃ to pass through. A failed ASC can no longer oxidise this ammonia, resulting in a strong ammonia odour that leads to complaints from freight forwarders, drivers, and surrounding communities.\u003c\/li\u003e\n\n        \u003cli\u003e\n\u003cstrong\u003e2. Secondary pollution and emission test failure:\u003c\/strong\u003e\u003cbr\u003e\n        A degraded ASC cannot effectively oxidise slip NH₃, causing exhaust ammonia content to exceed legal limits during annual inspections. Under certain conditions, the failed ASC may also generate N₂O (a potent greenhouse gas), making it impossible to meet Euro 6d or EPA emission requirements.\u003c\/li\u003e\n\n        \u003cli\u003e\n\u003cstrong\u003e3. SCR is fine, but ASC ageing triggers after‑treatment faults:\u003c\/strong\u003e\u003cbr\u003e\n        A common repair mistake is replacing only the SCR without replacing the ASC. After installing a new SCR, the ammonia smell persists, and the fault light cannot be cleared because the aged ASC is still unable to handle the slip.\u003c\/li\u003e\n\n        \u003cli\u003e\n\u003cstrong\u003e4. ASC blockage, thermal ageing, and poisoning – a chain reaction:\u003c\/strong\u003e\u003cbr\u003e\n        Ammonia reacts with sulfur oxides to form sulfate deposits that block the ASC substrate. Prolonged high‑temperature operation causes precious metal sintering (loss of active surface area). Oil vapour contamination also leads to rapid loss of ASC decomposition capability.\u003c\/li\u003e\n\n        \u003cli\u003e\n\u003cstrong\u003e5. Imbalance in the entire after‑treatment system:\u003c\/strong\u003e\u003cbr\u003e\n        Replacing the SCR with a non‑matched unit creates a urea dosing strategy mismatch. This exacerbates ammonia slip and quickly consumes the remaining ASC life, leading to premature system failure.\u003c\/li\u003e\n      \u003c\/ul\u003e\n    \u003c\/div\u003e\n  \u003c\/details\u003e\n\n  \u003c!-- Q7 – 如何避免SCR\/ASC中毒？ --\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003e\u003cspan class=\"q-mark\"\u003eQ7\u003c\/span\u003e How to prevent SCR\/ASC catalyst poisoning?\u003c\/summary\u003e\n    \u003cdiv class=\"answer-wrap\"\u003e\n      \u003cp\u003eCatalyst poisoning is one of the leading causes of SCR\/ASC failure. To minimise the risk and extend system life, follow these guidelines:\u003c\/p\u003e\n      \u003cul\u003e\n        \u003cli\u003e\n\u003cstrong\u003eUse high‑quality diesel fuel:\u003c\/strong\u003e Always use low‑sulfur diesel (EN 590 standard, sulfur \u0026lt; 10 ppm). High‑sulfur fuel produces sulfates that poison both SCR and ASC catalysts.\u003c\/li\u003e\n        \u003cli\u003e\n\u003cstrong\u003eUse ISO 22241‑compliant urea (AdBlue\/DEF):\u003c\/strong\u003e Never use cheap or non‑certified urea. Impurities such as aldehydes, biuret, heavy metals, and alkali metals accumulate on the catalyst surface, permanently reducing activity.\u003c\/li\u003e\n        \u003cli\u003e\n\u003cstrong\u003eMaintain the engine properly:\u003c\/strong\u003e Fix misfires, injector leaks, and excessive oil consumption immediately. Oil ash (phosphorus, zinc) and unburned fuel cause deposits on the catalyst.\u003c\/li\u003e\n        \u003cli\u003e\n\u003cstrong\u003eAvoid overheating:\u003c\/strong\u003e Ensure the DPF regeneration process does not cause uncontrolled temperature spikes above 650°C. Sustained high temperatures cause thermal sintering of precious metals.\u003c\/li\u003e\n        \u003cli\u003e\n\u003cstrong\u003eReplace ASC when replacing SCR:\u003c\/strong\u003e If the SCR is being replaced due to failure or ageing, always replace the ASC as well. A degraded ASC will be overwhelmed by the slip from a new SCR with different dosing characteristics.\u003c\/li\u003e\n        \u003cli\u003e\n\u003cstrong\u003eRegular diagnostic checks:\u003c\/strong\u003e Use an OBD scanner to monitor SCR efficiency, NH₃ slip, and backpressure. Early detection of efficiency loss allows for intervention before permanent damage occurs.\u003c\/li\u003e\n      \u003c\/ul\u003e\n    \u003c\/div\u003e\n  \u003c\/details\u003e\n\n  \u003c!-- Q8 – SCR\/ASC催化器堵塞常见是什么原因？ --\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003e\u003cspan class=\"q-mark\"\u003eQ8\u003c\/span\u003e What are the common causes of SCR\/ASC catalyst blockage?\u003c\/summary\u003e\n    \u003cdiv class=\"answer-wrap\"\u003e\n      \u003cp\u003eSCR\/ASC catalyst blockage (increased backpressure) can occur due to several reasons. The most common causes are:\u003c\/p\u003e\n      \u003cul\u003e\n        \u003cli\u003e\n\u003cstrong\u003eUrea deposit formation (crystallisation):\u003c\/strong\u003e When urea is not fully decomposed due to low exhaust temperatures or poor atomisation, it forms solid deposits (melamine and cyanuric acid) inside the catalyst channels.\u003c\/li\u003e\n        \u003cli\u003e\n\u003cstrong\u003eSoot accumulation:\u003c\/strong\u003e If the upstream DPF is failing or regeneration is incomplete, excessive soot particles pass through and accumulate on the SCR\/ASC, blocking the pores.\u003c\/li\u003e\n        \u003cli\u003e\n\u003cstrong\u003eSulfate deposits:\u003c\/strong\u003e Sulfur from high‑sulfur diesel reacts with ammonia to form ammonium sulfate and ammonium bisulfate, which condense and block the substrate.\u003c\/li\u003e\n        \u003cli\u003e\n\u003cstrong\u003eAsh buildup:\u003c\/strong\u003e Metallic ash from engine oil additives (especially zinc, calcium, and phosphorus) accumulates in the SCR\/ASC over time, reducing available surface area.\u003c\/li\u003e\n        \u003cli\u003e\n\u003cstrong\u003ePoor urea quality:\u003c\/strong\u003e Low‑quality urea contains impurities (biuret, aldehydes) that form solid precipitates at high temperatures.\u003c\/li\u003e\n        \u003cli\u003e\n\u003cstrong\u003eFaulty urea injector:\u003c\/strong\u003e A dripping or stuck‑open injector leads to over‑dosing, causing excess urea to crystallise inside the catalyst.\u003c\/li\u003e\n        \u003cli\u003e\n\u003cstrong\u003eLeaking turbocharger oil seals:\u003c\/strong\u003e Oil contamination can cause sticky deposits that block the catalyst channels.\u003c\/li\u003e\n      \u003c\/ul\u003e\n      \u003cp\u003e\u003cstrong\u003ePrevention:\u003c\/strong\u003e Use ISO 22241‑compliant urea, maintain low‑sulfur diesel, keep the engine and DPF in good condition, and avoid short trips that prevent the SCR from reaching operating temperature.\u003c\/p\u003e\n    \u003c\/div\u003e\n  \u003c\/details\u003e\n\n  \u003c!-- Q9 – 我们在哪里？ --\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003e\u003cspan class=\"q-mark\"\u003eQ9\u003c\/span\u003e Where are you located?\u003c\/summary\u003e\n    \u003cdiv class=\"answer-wrap\"\u003e\n      \u003cp\u003eOur company headquarters is located at:\u003c\/p\u003e\n      \u003cp\u003e\u003cstrong\u003eBuilding C, Zhongguan Innovation Center, Dongcheng 2nd Road, Pujiang Town, Minhang District, Shanghai, China\u003c\/strong\u003e\u003c\/p\u003e\n      \u003cp\u003eWe welcome business visits by appointment. Please contact us in advance to arrange a suitable time.\u003c\/p\u003e\n      \u003cp\u003eFor international customers, we offer global shipping and can arrange sample delivery for product evaluation prior to bulk orders.\u003c\/p\u003e\n    \u003c\/div\u003e\n  \u003c\/details\u003e\n\n  \u003c!-- Q10 – 如何联系我们？ --\u003e\n  \u003cdetails\u003e\n    \u003csummary\u003e\u003cspan class=\"q-mark\"\u003eQ10\u003c\/span\u003e How can I contact you?\u003c\/summary\u003e\n    \u003cdiv class=\"answer-wrap\"\u003e\n      \u003cp\u003eYou can reach our team directly via WhatsApp or email. We are happy to assist with any questions about products, sizing, orders, compatibility, or technical support.\u003c\/p\u003e\n\n      \u003cdiv class=\"contact-item\"\u003e\n        \u003cstrong\u003eDavin\u003c\/strong\u003e\u003cbr\u003e\n        WhatsApp: \u003ca href=\"https:\/\/wa.me\/8613335696939\" target=\"_blank\"\u003e+86 133 3569 6939\u003c\/a\u003e\u003cbr\u003e\n        E-mail: \u003ca href=\"mailto:KSRCAT@proton.me\"\u003eKSRCAT@proton.me\u003c\/a\u003e\n      \u003c\/div\u003e\n\n      \u003cdiv class=\"contact-item\"\u003e\n        \u003cstrong\u003eAlison\u003c\/strong\u003e\u003cbr\u003e\n        WhatsApp: \u003ca href=\"https:\/\/wa.me\/8615082475717\" target=\"_blank\"\u003e+86 150 8247 5717\u003c\/a\u003e\u003cbr\u003e\n        E-mail: \u003ca href=\"mailto:Ksrcatalytic@gmail.com\"\u003eKsrcatalytic@gmail.com\u003c\/a\u003e\n      \u003c\/div\u003e\n\n      \u003cdiv class=\"contact-item\"\u003e\n        \u003cstrong\u003eMia\u003c\/strong\u003e\u003cbr\u003e\n        WhatsApp: \u003ca href=\"https:\/\/wa.me\/8613681711685\" target=\"_blank\"\u003e+86 136 8171 1685\u003c\/a\u003e\u003cbr\u003e\n        E-mail: \u003ca href=\"mailto:Kesairay@proton.me\"\u003eKesairay@proton.me\u003c\/a\u003e\n      \u003c\/div\u003e\n\n      \u003cp\u003eWe typically respond within 24 hours (Monday–Saturday). Please include your order number or vehicle details for faster assistance.\u003c\/p\u003e\n    \u003c\/div\u003e\n  \u003c\/details\u003e\n\u003c\/div\u003e","brand":"SVIPCAT Store","offers":[{"title":"305x76mm \/ V - Euro5 \/ SCR+ASC(2in）coating","offer_id":54591810339162,"sku":null,"price":0.0,"currency_code":"GBP","in_stock":false},{"title":"305x76mm \/ Cu - Euro6 \/ SCR+ASC(2in）coating","offer_id":54591810371930,"sku":null,"price":0.0,"currency_code":"GBP","in_stock":false},{"title":"305x76mm \/ Fe - Euro6 \/ SCR+ASC(2in）coating","offer_id":54591810404698,"sku":null,"price":0.0,"currency_code":"GBP","in_stock":false},{"title":"305x100mm \/ V - Euro5 \/ SCR+ASC(2in）coating","offer_id":54591810437466,"sku":null,"price":0.0,"currency_code":"GBP","in_stock":false},{"title":"305x100mm \/ Cu - Euro6 \/ SCR+ASC(2in）coating","offer_id":54591810470234,"sku":null,"price":0.0,"currency_code":"GBP","in_stock":false},{"title":"305x100mm \/ Fe - Euro6 \/ SCR+ASC(2in）coating","offer_id":54591810503002,"sku":null,"price":0.0,"currency_code":"GBP","in_stock":false},{"title":"305x127mm \/ V - Euro5 \/ SCR+ASC(2in）coating","offer_id":54591810535770,"sku":null,"price":0.0,"currency_code":"GBP","in_stock":false},{"title":"305x127mm \/ Cu - Euro6 \/ SCR+ASC(2in）coating","offer_id":54591810568538,"sku":null,"price":0.0,"currency_code":"GBP","in_stock":false},{"title":"305x127mm \/ Fe - Euro6 \/ SCR+ASC(2in）coating","offer_id":54591810601306,"sku":null,"price":0.0,"currency_code":"GBP","in_stock":false},{"title":"305x152mm \/ V - Euro5 \/ SCR+ASC(2in）coating","offer_id":54591810634074,"sku":null,"price":0.0,"currency_code":"GBP","in_stock":false},{"title":"305x152mm \/ Cu - Euro6 \/ SCR+ASC(2in）coating","offer_id":54591810666842,"sku":null,"price":0.0,"currency_code":"GBP","in_stock":false},{"title":"305x152mm \/ Fe - Euro6 \/ SCR+ASC(2in）coating","offer_id":54591810699610,"sku":null,"price":0.0,"currency_code":"GBP","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0958\/5164\/3226\/files\/1_4bc64615-23a3-4be5-aee5-367e4e8a61ee.jpg?v=1786870653","url":"https:\/\/www.svipcat.com\/products\/%cf%86305mm-12in-diesel-vehicle-scr-asc-filter","provider":"SVIPCAT Store","version":"1.0","type":"link"}