ANNEX VIIU.K. VERIFYING THE DURABILITY OF ENGINE SYSTEMS
1.INTRODUCTIONU.K.
1.1.This Annex sets out the procedures for selecting engines to be tested over a service accumulation schedule for the purpose of determining deterioration factors. The deterioration factors shall be applied in accordance with the requirements of point 3.6 of this Annex to the emissions measured according to Annex III.U.K.
1.2.This Annex also sets out the emission and non-emission-related maintenance carried out on engines undergoing a service accumulation schedule. Such maintenance shall conform to the maintenance performed on in-service engines and shall be communicated to owners of new engines and vehicles.U.K.
2.SELECTION OF ENGINES FOR ESTABLISHING USEFUL LIFE DETERIORATION FACTORSU.K.
2.1.Engines shall be selected from the engine family defined in accordance with point 6 of Annex I for emission testing in order to establish useful life deterioration factors.U.K.
2.2.Engines from different engine families may be further combined into families based on the type of exhaust after-treatment system utilised. In order to place engines with different numbers of cylinders and different cylinder configuration but having the same technical specifications and installation for the exhaust after-treatment systems into the same engine-aftertreatment system family, the manufacturer shall provide data to the approval authority that demonstrates that the emissions reduction performance of such engine systems is similar.U.K.
2.3.One engine representing the engine-aftertreatment system family as determined in accordance with point 2.2, shall be selected by the engine manufacturer for testing over the service accumulation schedule defined in point 3.2, and shall be reported to the approval authority before any testing commences.U.K.
2.3.1.If the approval authority decides that the worst case emissions of the engine-aftertreatment system family can be characterised better by another engine then the test engine shall be selected jointly by the approval authority and the engine manufacturer.U.K.
3.ESTABLISHING USEFUL LIFE DETERIORATION FACTORSU.K.
3.1. General U.K.
Deterioration factors applicable to an engine-aftertreatment system family are developed from the selected engines based on a service accumulation schedule that includes periodic testing for gaseous and particulate emissions over the WHTC and WHSC tests.
3.2. Service accumulation schedule U.K.
Service accumulation schedules may be carried out at the choice of the manufacturer by running a vehicle equipped with the selected engine over an in-service accumulation schedule or by running the selected engine over a dynamometer service accumulation schedule.
3.2.1. In-service and dynamometer service accumulation U.K.
3.2.1.1.The manufacturer shall determine the form and extent of the distance, the service accumulation and the ageing cycle for engines, consistent with good engineering practice.U.K.
3.2.1.2.The manufacturer shall determine the test points where gaseous and particulate emissions will be measured over the hot WHTC and WHSC tests. The minimum number of test points shall be three, one at the beginning, one approximately in the middle and one at the end of the service accumulation schedule.U.K.
3.2.1.3.The emission values at the start point and at the useful life end point calculated in accordance with point 3.5.2 shall meet the limit values specified in the table of Annex I to Regulation (EC) No 595/2009 but individual emission results from the test points may exceed those limit values.U.K.
3.2.1.4.At the request of the manufacturer and with the agreement of the approval authority, only one test cycle (either the hot WHTC or WHSC test) needs to be run at each test point, with the other test cycle run only at the beginning and at the end of the service accumulation schedule.U.K.
3.2.1.5.Service accumulation schedules may be different for different engine-aftertreatment system families.U.K.
3.2.1.6.Service accumulation schedules may be shorter than the useful life period, but shall not be shorter than shown in the table in point 3.2.1.8.U.K.
3.2.1.7.For engine dynamometer service accumulation, the manufacturer shall provide the applicable correlation between the service accumulation period (driving distance) and engine dynamometer hours, for example, fuel consumption correlation, vehicle speed versus engine revolutions correlation, etc.U.K.
3.2.1.8. Minimum service accumulation period U.K.
Table 1
Minimum service accumulation period
| Category of vehicle in which engine will be installed | Minimum service accumulation period | Useful life (Article of Regulation (EC) No 595/2009) |
|---|---|---|
| Category N1 vehicles | 160 000 km | Article 4(2)(a) |
| Category N2 vehicles | 188 000 km | Article 4(2)(b) |
| Category N3 vehicles with a maximum technically permissible mass not exceeding 16 tonnes | 188 000 km | Article 4(2)(b) |
| Category N3 vehicles with a maximum technically permissible mass exceeding 16 tonnes | 233 000 km | Article 4(2)(c) |
| Category M1 vehicles | 160 000 km | Article 4(2)(a) |
| Category M2 vehicles | 160 000 km | Article 4(2)(a) |
| Category M3 vehicles of classes I, II, A and B as defined in Annex I to Directive 2001/85/EC, with a maximum technically permissible mass not exceeding 7,5 tonnes | 188 000 km | Article 4(2)(b) |
| Category M3 vehicles of classes III and B as defined in Annex I to Directive 2001/85/EC with a maximum technically permissible mass exceeding 7,5 tonnes | 233 000 km | Article 4(2)(c) |
3.2.1.9.Accelerated ageing is permitted by adjusting the service accumulation schedule on a fuel consumption basis. The adjustment shall be based on the ratio between the typical in-use fuel consumption and the fuel consumption on the ageing cycle, but the fuel consumption on the ageing cycle shall not exceed the typical in-use fuel consumption by more than 30 %.U.K.
3.2.1.10.The service accumulation schedule shall be fully described in the application for type-approval and reported to the type-approval authority before the start of any testing.U.K.
3.2.2.If the type-approval authority decides that additional measurements need to be carried out on the hot WHTC and WHSC tests between the points selected by the manufacturer it shall notify the manufacturer. The revised service accumulation schedule shall be prepared by the manufacturer and agreed by the approval authority.U.K.
3.3. Engine testing U.K.
3.3.1. Engine system stabilisation U.K.
3.3.1.1.For each engine-aftertreatment system family, the manufacturer shall determine the number of hours of vehicle or engine running after which the operation of the engine-aftertreatment system has stabilised. If requested by the approval authority the manufacturer shall make available the data and analysis used to make this determination. As an alternative, the manufacturer may elect to run the engine between 60 and 125 hours or the equivalent mileage on the ageing cycle to stabilise the engine-aftertreatment system.U.K.
3.3.1.2.The end of the stabilisation period determined in point 3.3.1.1 will be deemed to be the start of the service accumulation schedule.U.K.
3.3.2. Service accumulation testing U.K.
3.3.2.1.After stabilisation, the engine shall be run over the service accumulation schedule selected by the manufacturer, as described in point 3.2. At the periodic intervals in the service accumulation schedule determined by the manufacturer, and, where appropriate, also stipulated by the approval authority according to point 3.2.2 the engine shall be tested for gaseous and particulate emissions over the hot WHTC and WHSC tests. In accordance with point 3.2.1.4, if it has been agreed that only one test cycle (hot WHTC or WHSC) be run at each test point, the other test cycle (hot WHTC or WHSC) shall be run at the beginning and end of the service accumulation schedule.U.K.
3.3.2.2.During the service accumulation schedule, maintenance shall be carried out on the engine according to the requirements of point 4.U.K.
3.3.2.3.During the service accumulation schedule, unscheduled maintenance on the engine or vehicle may be performed, for example if the OBD system has specifically detected a problem that has resulted in the malfunction indicator (hereinafter ‘MI’) being activated.U.K.
3.4. Reporting U.K.
3.4.1.The results of all emission tests (hot WHTC and WHSC) conducted during the service accumulation schedule shall be made available to the approval authority. If any emission test is declared to be void, the manufacturer shall provide an explanation of why the test has been declared void. In such a case, another series of emission tests over the hot WHTC and WHSC tests shall be carried out within the following 100 hours of service accumulation.U.K.
3.4.2.The manufacturer shall retain records of all information concerning all the emission tests and maintenance carried out on the engine during the service accumulation schedule. This information shall be submitted to the approval authority along with the results of the emission tests conducted over the service accumulation schedule.U.K.
3.5. Determination of deterioration factors U.K.
3.5.1.For each pollutant measured on the hot WHTC and WHSC tests at each test point during the service accumulation schedule, a ‘best fit’ linear regression analysis shall be made on the basis of all test results. The results of each test for each pollutant shall be expressed to the same number of decimal places as the limit value for that pollutant, as shown in the table of Annex I to Regulation (EC) No 595/2009, plus one additional decimal place. In accordance with point 3.2.1.4 of this Annex, if it has been agreed that only one test cycle (hot WHTC or WHSC) be run at each test point and the other test cycle (hot WHTC or WHSC) run only at the beginning and at the end of the service accumulation schedule, the regression analysis shall be made only on the basis of the test results from the test cycle run at each test point.U.K.
At the request of the manufacturer and with the prior approval of the approval authority a non-linear regression shall be permitted.
3.5.2.The emission values for each pollutant at the start of the service accumulation schedule and at the useful life end point that is applicable for the engine under test shall be calculated from the regression equation. If the service accumulation schedule is shorter than the useful life period, the emission values at the useful life end point shall be determined by extrapolation of the regression equation as determined in point 3.5.1.U.K.
3.5.3.The deterioration factor for each pollutant is defined as the ratio of the applied emission values at the useful life end point and at the start of the service accumulation schedule (multiplicative deterioration factor).U.K.
At the request of the manufacturer and with the prior approval of the approval authority, an additive deterioration factor for each pollutant may be applied. The additive deterioration factor shall be considered as the difference between the calculated emission values at the useful life end point and at the start of the service accumulation schedule.
If the calculation results in a value of less than 1,00 for a multiplicative DF, or less than 0,00 for an additive DF, then the deterioration factor shall be 1,0 or 0,00, respectively.
An example for determination of deterioration factors by using linear regression is shown in Figure 1.
Mixing of multiplicative and additive deterioration factors within one set of pollutants shall not be permitted.
In accordance with point 3.2.1.4, if it has been agreed that only one test cycle (hot WHTC or WHSC) be run at each test point and the other test cycle (hot WHTC or WHSC) run only at the beginning and end of the service accumulation schedule, the deterioration factor calculated for the test cycle that has been run at each test point shall be applicable also for the other test cycle.
3.6. Assigned deterioration factors U.K.
3.6.1.As an alternative to using a service accumulation schedule to determine deterioration factors, engine manufacturers may choose to use the following assigned multiplicative deterioration factors:U.K.
Table 2
Deterioration factors
Assigned additive deterioration factors are not given. It shall not be permitted to transform the assigned multiplicative deterioration factors into additive deterioration factors.
3.7. Application of deterioration factors U.K.
3.7.1.The engines shall meet the respective emission limits for each pollutant, as given in the table of Annex I to Regulation (EC) No 595/2009, after application of the deterioration factors to the test result as measured in accordance with Annex III (egas, ePM). Depending on the type of deterioration factor (DF), the following provisions shall apply:U.K.
(a)
Multiplicative: (egas or ePM) x DF ≤ emission limit
(b)
Additive: (egas or ePM) + DF ≤ emission limit
3.7.2.The manufacturer may choose to carry across the DFs determined for an engine after treatment system family to an engine system that does not fall into the same engine-aftertreatment system family. In such cases, the manufacturer shall demonstrate to the approval authority that the engine system for which the aftertreatment system family was originally tested and the engine system for which the DFs are being carried across have the same technical specifications and installation requirements on the vehicle and that the emissions of such engine or engine system are similar.U.K.
3.7.3.The deterioration factors for each pollutant on the appropriate test cycle shall be recorded in points 1.4.1 and 1.4.2 of the Addendum to Appendix 5 to Annex I and in points 1.4.1 and 1.4.2 of the Addendum to Appendix 7 to Annex I.U.K.
3.8. Checking of conformity of production U.K.
3.8.1.Conformity of production for emissions compliance shall be checked on the basis of the requirements of Section 7 of Annex I.U.K.
3.8.2.The manufacturer may choose to measure the pollutant emissions before any exhaust after-treatment system at the same time as the type-approval test is being performed. In doing so, the manufacturer may develop an informal deterioration factor separately for the engine and the aftertreatment system that may be used by the manufacturer as an aid to end of production line auditing.U.K.
3.8.3.For the purposes of type-approval, only the deterioration factors according to points 3.5 or 3.6 shall be recorded in points 1.4.1 and 1.4.2 of the Addendum to Appendix 5 and points 1.4.1 and 1.4.2 of the Addendum to Appendix 7 to Annex I.U.K.
4.MAINTENANCEU.K.
For the purpose of the service accumulation schedule, maintenance shall be performed in accordance with the manufacturer’s manual for service and maintenance.
4.1. Emission-related scheduled maintenance U.K.
4.1.1.Emission-related scheduled maintenance for purposes of conducting a service accumulation schedule shall occur at the same distance or equivalent intervals to those that will be specified in the manufacturer’s maintenance instructions to the owner of the engine or vehicle. This maintenance schedule may be updated as necessary throughout the service accumulation schedule provided that no maintenance operation is deleted from the maintenance schedule after the operation has been performed on the test engine.U.K.
4.1.2.The engine manufacturer shall specify for the service accumulation schedule the adjustment, cleaning and maintenance (where necessary) and scheduled exchange of the following items:U.K.
(a)
filters and coolers in the exhaust gas recirculation system;
(b)
positive crankcase ventilation valve, if applicable;
(c)
fuel injector tips (cleaning only);
(d)
fuel injectors;
(e)
turbocharger;
(f)
electronic engine control unit and its associated sensors and actuators;
(g)
particulate aftertreatment system (including related components);
(h)
deNOx system;
(i)
exhaust gas recirculation system, including all related control valves and tubing;
(j)
any other exhaust after-treatment system.