diesel engines charge air pressure will be higher than its design pressure
If you mean the fact that a ‘90’s era 6.5 diesel was designed for a pressure up to about 10 lbs max and I regularly hit 20 with mine then what happens is you get almost double the horsepower.
However you can also get an increase head gasket failure rate. To combat this we use head studs from ARP when we rebuild these engines. We also use top grade head gaskets and sometimes we might even ring the cylinder at the top. These upgrades can be expensive but almost always guarantee the top end will easily handle over 30 psi. Not bad for an old lightweight diesel. The big question is will the bottom end stay together.
Now for newer duramaxes and to some extent the other brands of newer diesel trucks coming out with stock engines pushing 600 HP their engines are already designed to handle much higher pressures and tunes. Often being pushed over 800 HP. With some mods they are pushed over 1000 HP. However the Lifespan of one of these engines pushing 1200HP is sometimes so short it only lasts for 2 dyno pulls. And don’t even consider asking that truck to pull a load up a long grade at that power level. The lifespan of the engine starts getting shorter and shorter the more power you pull out of it. If you want your engine to last literally forever then take that stock 600hp engine and derate it down to 450 HP. Then it will probably outlast you and still get the work done just fine that you are asking of it.
Low charge air pressure
Possible Turbocharger-Related Causes
Heavily fouled filter silencer.
Compressor fouled.
Compressor damaged.
Turbine blade damaged.
Nozzle ring damaged.
Cover ring eroded.
Possible Non-Turbocharger-Related Causes
Turbine back pressure too high.
Air/Gas leaks.
Ambient pressure of engine room reduced.
Defective manometer indication
Damage Limitation Procedures
If the above is noticed please contact our service team.
High charge air pressure for clean engines
One of the first installation of A175-L turbochargers is onboard the Alexander Maersk, a 1068 TEU container ship, chosen as a demonstrator for the ‘Green Ship of the Future’ project, run under the auspices of the Danish government to targets development of emissions-reducing technologies. This installation also benefits from an experimental exhaust gas recirculation installation, which necessitates use of ABB’s variable turbine geometry (VTG) technology.
The exact designation of the turbocharger is A175-L34T with “T” denoting VTG technology - and according to ABB Turbocharging application engineer Klaus Fusstetter, there are three distinct sets of benefits.
“First, due to its very high efficiency, this state-of-the-art turbocharger gives significant improvements in fuel consumption and the formation of oxides of nitrogen (NOx)compared to the older unit it has replaced, “ Fusstetter notes. “Second, the inclusion of VTG technology allows close matching of the quantity of charge air reaching the combustion chamber to the amount of fuel injected. And, third, VTG is an essential part of the EGR system fitted on the Alexander Maersk’s main engine to significantly reduce NOx.”
In the VTG turbochargers, the normal fixed nozzle ring upstream of the turbine is replaced by a nozzle ring with adjustable vanes. Under electronic control, the adjustable vanes allow the pressure of the exhaust gases impinging on the turbocharger turbine to be regulated. This varies the speed of the compressor wheel and so allows the quantity of charge air delivered to the engine’s combustion chambers to be varied.
“VTG technology thus allows close matching of the power the engine produces to the power needed to propel the ship at a given time and under prevailing load and sea conditions,” Fusstetter adds. “The benefits are optimised fuel consumption and related exhaust emissions. Further, the ability to regulate charge air delivery across the engine’s complete operating profile gives improved engine response under load changes.”
EGR is common on smaller distillate-burning diesel engines, but hitherto has not been suitable for use with HFO. On the Alexander Maersk, VTG technology gives the necessary control over combustion air delivery needed to supply the correct amounts of air, fuel and exhaust gas into the combustion chamber, Fusstetter explains. “In an EGR system, the engine exhaust gases serve as a source of inert gases. Cleaned and cooled, they are re-introduced into the combustion chamber where they serve to reduce the combustion temperature peaks responsible for well over 90% of NOx formation. A key factor is achieving the correct proportions of inert gas, fuel and charge air. The level of control we can achieve with our VTG technology makes it an ideal tool for regulating the level of charge air delivery.”
Fixed price servicing
ABB Turbocharging has successfully offered its OPAC operation performance package to end users of engines fitted with ABB turbochargers for some time. The company has now extended the package to include engine builders.
OPAC offers delegation of responsibility for maintenance, repair and planned overhauls of turbochargers to ABB’s network of service outlets. For a fixed price, covering an agreed number of operating hours, ABB says it can ensure prompt, well planned servicing and preventive maintenance using only original ABB Turbocharger service parts, carried out by qualified personnel.
The first OPAC agreement with an engine builder covers ABB Turbocharging’s TPL69A turbochargers on type LH46LA/6L35MC engines from Hanshin Diesel of Japan, and thus offers the OPAC service to Hanshin’s new engine customers. Like all OPAC agreements, the arrangement with Hanshin is customised to the specific needs of the turbocharger or turbochargers in question, based on a detailed assessment of the turbocharger’s operating profile by ABB’s service department. This appraisal includes its condition at the outset of OPAC servicing, its previous service history, its expected annual running hours and the planned ports of call of the ship.
Under the Hanshin agreement, OPAC is integrated into the diesel engine builder’s own Hanasys-Expert (HS-EX) control system, which supplies additional input to the OPAC service event planning process. HS-EX transmits engine operating data from ship to shore where, together with other information relevant to the ship, it is monitored and analysed by Hanshin’s customer support team to work out suitable service schedules. This solution underlines a key feature of OPAC – its adaptability for working together with the customers’ own maintenance systems.
ABB Turbocharging offers two OPAC modules. OPAC base covers regular overhauls and service needs related to wear and tear while OPAC premium allows a number of unforeseen circumstances to be included into an agreement, for example foreign object damage.
The first OPAC agreement to be signed was with Rotterdam-based Stolt Nielsen Transportation Group and has been running since 2006. The contract covers 74 VTR turbochargers on 20 ships, all with diesel-electric propulsion systems, and has proved satisfying for the customer.
Subsequent OPAC agreements have been concluded with K Line in Japan, and China Shipping Container Lines (CSCL) and COSCO Dalian Ocean Shipping Company in China.
On the end user side, an OPAC agreement was recently signed with French ferry operator SNCM.
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