GB/T 18881-2017Catalyst for light-duty petrol vehicle exhaust purification (English PDF)

Foreword

This Standard was drafted in accordance with the rules given in GB/T 1.1-2009.

This Standard replaces GB/T 18881-2009 "Catalyst for petrol vehicle exhaust purification".

Compared with GB/T 18881-2009, in addition to the editorial modifications, the main technical changes are as follows.

- added the pollutant emission limit and measurement method of light-duty petrol vehicle (China V-stage) (see Clause 2);

- modified the hole density value in product classification table 1 (see Clause 4);

- modified the engine bench performance conversion rate requirements of fresh catalyst (see 5.6);

- added the terms and definitions of space velocity, precious metal content, coating weight loss ratio, back pressure, nominal back pressure, percentage of plugged hole of catalyst (see 3.5~3.10);

- added the requirements and test methods of precious metal content and proportion (see 5.3, 6.3);

- added the requirements and test methods of coating weight loss ratio (see 5.4, 6.4);

- added the product requirements and test methods of back pressure (see 5.5, 6.5).

1 Scope

This Standard specifies the requirements, test methods, inspection rules, marks, packaging, transport, storage and quality certificate of catalyst for light-duty petrol vehicle exhaust purification.

This Standard is applicable to the catalyst for light-duty petrol vehicle exhaust purification which uses cordierite honeycomb ceramic carrier as matrix and loads with rare earth, precious metal or other metal and other active components.

2 Normative references

The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.

GB/T 2828.1, Sampling procedures for inspection by attribute - Part 1. Sampling schemes indexed by acceptance quality limit (AQL) for lot-by-lot inspection

GB/T 5181, Automotive emission - Terms and definitions

GB/T 8170, Rules of rounding off for numerical values & expression and judgement of limiting values

GB/T 17803, Designation system for rare earth products

GB 18352.3, Limits and measurement methods for emissions from light-duty vehicles

GB 18352.5, Limits and measurement methods for emissions from light-duty vehicles (CHINA 5)

GB/T 18377, Requirements and measurement methods of catalytic converters for petrol vehicles

GB/T 23277, Chemical analysis methods of catalysts containing precious metals - Determination of platinum palladium and rhodium in automobile exhaust-purifying catalysts - Spectrophotometry

6 Test methods

7 Inspection rules

7.5.3 When the inspection results of precious metal content and proportion, coating weight loss ratio, back pressure and catalytic performance engine bench are unqualified, take double samples for re-inspection of failed items. If there are still unqualified items, the product shall be determined as unqualified.

7.5.4 When the inspection results of overall vehicle performance and durability are unqualified, it shall be settled by the supplier and the purchaser via negotiation.

8 Marks, packaging, transport, storage and quality certificate