Appendix 7 – Checklist for an engine parameter check method (Refer to 6.2.2.5 of the NO_x Technical Code 2008)

  1 For some of the parameters listed below, more than one survey possibility exists. In such cases, as a guideline, any one of, or a combination of, the below listed methods may be sufficient to show compliance. As approved by the Administration, the shipowner, supported by the applicant for engine certification, may choose which method is applicable.

• .1 parameter 'injection timing and ignition timing':

  • .1 Fuel cam position (individual cam or camshaft if cams are not adjustable):

    • - optional (dependent on design): position of a link between the cam and the pump drive,

    • - optional for sleeve-metered pumps: variable injection timing (VIT) index and cam position or position of the barrel, or

    • - other sleeve metering device;

  • .2 start of delivery for certain fuel rack positions (dynamic pressure measurement);

  • .3 opening of injection valve for certain load points, e.g., using a Hall sensor or acceleration pick-up;

  • .4 load-dependent operating values for charge air pressure, combustion peak pressure, charge air temperature, exhaust gas temperature versus graphs showing the correlation with NO_x. Additionally, it shall be ensured that the compression ratio corresponds to the initial certification value (see 1.7) and

  • .5 timing indicator or timing light.

  • Note: To assess the actual timing, it is necessary to know the allowable limits for meeting the emission limits or even graphs showing the influence of timing on NO_x, based on the test-bed measurement results.

• .2 parameter “injection nozzle”:

  • .1 specification and component identification number;

• .3 parameter “injection pump”:

  • .1 component identification number (specifying plunger and barrel design);

• .4 parameter “fuel cam”:

  • .1 component identification number (specifying shape);

  • .2 start and end of delivery for a certain fuel rack position (dynamic pressure measurement);

• .5 parameter “injection pressure”:

  • .1 only for common-rail systems: load-dependent pressure in the rail, graph showing correlation with NO_x;

• .6 parameter “combustion chamber”:

  • .1 component identification numbers for the cylinder head and piston head;

• .7 parameter “compression ratio”:

  • .1 check for actual clearance;

  • .2 check for shims in piston rod or connecting rod;

• .8 parameter “turbocharger type and build”:

  • .1 model and specification (identification numbers);

  • .2 load-dependent charge air pressure, graph showing the correlation with NO_x;

• .9 parameter “charge air cooler, charge air heater”:

  • .1 model and specification;

  • .2 load-dependent charge air temperature corrected to reference conditions, graph showing the correlation with NO_x;

• .10 parameter “valve timing” (only for 4-stroke engines with inlet valve closure before bottom dead centre (BDC)):

  • .1 cam position;

  • .2 check actual timing;

• .11 parameter “water injection” (for assessment: graph showing influence on NO_x):

  • .1 load-dependent water consumption (monitoring);

• .12 parameter “emulsified fuel” (for assessment: graph showing influence on NO_x):

  • .1 load-dependent fuel rack position (monitoring);

  • .2 load-dependent water consumption (monitoring);

• .13 parameter “exhaust gas recirculation” (for assessment: graph showing influence on NO_x):

  • .1 load-dependent mass flow of recirculated exhaust gas (monitoring);

  • .2 CO₂ concentration in the mixture of fresh air and recirculated exhaust gas, i.e. in the “scavenge air” (monitoring);

  • .3 O₂ concentration in the “scavenge air” (monitoring);

• .14 parameter “selective catalytic reduction” (SCR):

  • .1 load-dependent mass flow of reducing agent (monitoring) and additional periodical spot checks on NO_x concentration after SCR (for assessment: graph showing influence on NO_x).

  2 For engines with selective catalytic reduction (SCR) without feedback control, optional NO_x measurement (periodical spot checks or monitoring) is useful to show that the SCR efficiency still corresponds to the state at the time of certification regardless of whether the ambient conditions or the fuel quality led to different raw emissions.