Ref: PRCSHNA                                                                                          Date: 3rd December 2010

EU STAGE 3B– THE BOLDEST MOVE YET IN EMISSION TECHNOLOGY

January 1^st, 2011 will see the implementation of EU stage 3b engine emission norms for off-road engines in the power range of 130kW – 560 kW. This also happens to coincide with the US Environmental Protection Agency (EPA) Tier 4i emission controls on the same date. With the smallest size engine within the Konecranes range at 147 kW, this means an immediate engine change across the range of forklifts, container handlers and reachstackers. EU rules governing implementation allow a certain run-over into 2011 with the current EU stage 3a engines however; this is simply a timing issue. Fortunately, Konecranes have been working towards these norms for many months and are fully prepared for full and immediate implementation.

EU stage 3b is the latest landmark in the control of exhaust emissions which stretch back to EU stage 1 that was first introduced in 1995. The legislated and measured emissions are Nitrogen Oxides (NOx). Hydro Carbons (HC), Carbon Monoxide (CO) and Particle matters (PM) – the latter also known as soot or black smoke.

The early emission controls through EU stage 2 and the current EU stage 3a norms have seen all these elements fall in value from anything from 30 to 60% of the original EU stage 1 requirement. Stage 3b represents the most challenging and bold progression yet that will see a further 50% fall in NOx and HC and a massive 90% in PM over the current EU stage 3a levels. Emissions will therefore present a tiny fraction of the machines supplied as recently as 2002 when EU stage 2 was first introduced. In fact NOx and PM will be reduced as much as over 95% with EU stage 4 (implementation in 2014).

Being of Scandinavian origin, and with close links to both Scania and Volvo Konecranes have introduced a Selective Catalytic Reduction (SCR) emission control system that has been used on road going vehicles for a number of years. The problem engine manufacturers have faced is that by the effect of minimising PM during the in-cylinder combustion process has the effect of increasing the NOx proportionally. Therein lies the need of a trade-off and a conundrum for the engine suppliers. Do they minimise NOx and allow PM to flow freely and catch the soot in a filtration system or do they control the PM with a much cleaner burn and treat the NOx post burn?

The SCR system adopts the latter. Exhaust gases leave the engine and pass through a single catalytic converter. PM already satisfies Stage 3b requirements at this point. Once passed the catalyser, UREA (ad-blue) is injected into the gases which negate the NOx. A secondary SCR catalyst then gathers the combined gases / ad-blue mix before ejecting into the atmosphere. Ad-blue will therefore be part of the engine fuel system with its own separate tank and fuel gauge. Ad-blue will be used at a rate of 2,5 - 5% of diesel and the tank size has been designed around two diesel tankfills to one ad-blue tank. Naturally the Ad-blue filler is located in the same location as the diesel tank for convenience. In the event of Ad-blue gauges and alarms being ignored with levels falling below a pre-determined point, engine speed restrictions will then be automatically enforced.

The addition of ad-blue and the disciplines associated with filling will be something users will have to become accustomed in the same way on-road users have been. The advantages however are numerous. Engines have been released of the restrictions that have strangled their performance with emission control. Engines will have greater power and incredibly as much as 25 – 50 % extra torque depending on the engine speed (torque being the factor that controls hydraulic performance). Consequently engines will not have to work as hard thus reducing fuel consumption by a further 5-10%. Noise too has been reduced by app 2 dB(A). Such has been the increase in performance engine displacement has been reduced to 5 litres on the Volvo engines and yet both torque and power are higher. 4 cylinder engines are also available which seems unthinkable on machines so large – in the UK we will try to resist such changes. Unfortunately one victim of the EU stage 3b implementation will be the Scania 9 litre engine which has been the powerhouse of the SMV range for the past 16 years. The 12 litre DC-12 engine will be replaced with a DC-13 – 13 litre unit developing an incredible 1950Nm at just 1200 rpm (the old DC-12 produced 1544Nm @ 1400rpm). The Scania 13 litre will represent standard UK supply for lift trucks above 33 tonne capacity and the full range of laden reachstackers.

Electronic machine control is now a standard feature across the range of Konecranes lift trucks so this will allow machine and engine settings to be totally tailored around a specific customer application to optimise machine performance around the customer’s needs.

Cummins engines, which have represented an option on Konecranes equipment, it would appear, have adopted the opposite approach by reducing NOx during the burn process at the expense of allowing PM to increase. This is then trapped in traditional soot filters which, previously an option now becomes a compulsory fit.  Unlike the SCR system, the Cummins option does not adopt new technology with the same radicalism however, whilst engine figures have yet to be released, we can expect power and torque figures to be similar to that of the current 3a engines. Of course, soot filters will require additional extraction and cleaning via various methods.

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