COSTS OF SELECTED HEAVY-DUTY
DIESEL ENGINE EMISSION CONTROL
COMPONENTS
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COSTS OF SELECTED HEAVY-DUTY
DIESEL ENGINE EMISSION CONTROL
COMPONENTS
FINAL REPORT
February 8, 1985
Submitted to:
Submitted by:
Standards Development and Support Branch
Office of Mobile Sources
U.S. Environmental Protection Agency
2565 Plymouth Road
Ann Arbor, Michigan 48105
Jack Faucett Associates, Inc.
5454 Wisconsin Avenue
Suite 1155
Chevy Chase, Maryland 20015
and
Mueller Associates, Inc.
Consulting Engineers
1401 S. Edgewood Street
Baltimore, Maryland 21227
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TABLE OF CONTENTS
Paqe
I. INTRODUCTION 1
II. TURBOCHARGING 3
III. ENGINE COOLANT AIR-TO-LIQUID 6
INTERCOOLING
IV. SEPARATE SYSTEM AIR-TO-LIQUID 8
INTERCOOLING
V. AIR-TO-AIR INTERCOOLING 10
VI. UNIT INJECTOR FUEL INJECTION SYSTEM 12
VII. HIGH PRESSURE FUEL INJECTION (JERK-PUMP) 14
SYSTEM
VIII. ELECTRONIC CONTROLS • 17
IX. CERAMIC MONOLITH TRAP 21
X. CATALYTIC MATERIAL 31
XI. BURNER HOUSING AND IGNITION SYSTEM 33
XII. REFERENCES/SOURCES OF INFORMATION 36
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I. INTRODUCTION
Background
The Environmental Protection Agency (EPA) is currently
developing rules applicable to the control of NO and particulate
emissions from heavy-duty engines (HDE). The cost of emission
control components and/or systems is one of the factors which is
considered during the development of these rules. This report
presents some estimated costs of selected heavy-duty diesel
engine emission control components. The effort was conducted for
Jack Faucett Associates under their prime contract with the U.S.
Environmental Protection Agency (EPA Contract No. 68-03-3244).
The remainder of this section provides some considerations
surrounding the approach to estimating costs, while the remaining
sections of the report describe the systems or system configura-
tions considered and the components that were costed. The sys-
tems/components addressed include: turbocharging a naturally
aspirated engine, engine coolant air-to-liquid intercooling (also
referred to as aftercooling), separate air-to-liquid intercool-
ing, air-to-air intercooling, high pressure unit injectors, high
pressure injection pump, electronic controls, ceramic monolith
particulate trap with electrical heat regeneration, catalytic
material for ceramic fiber trap, and burner housing and ignition
system for a diesel fuel burner regeneration system.
Cost Estimation Methodology
The method used to generate cost estimates draws heavily on
previous experience in estimating new component costs. Develop-
ing engineering estimates of finished product costs is a
predictive exercise similar to other types of forecasting
commonly performed. Engineering cost analysis has an advantage
over most other types of forecasting in that more "hard"
information is usually at hand and very analogous manufacturing
activities have been performed in the past for which information
is available. The best approach would have been to perform a
rigorous "bottom-up" engineering and cost analysis which
addressed each part of every component. However, the time and
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effort committed to this task precluded such a rigorous approach.
Experience has shown that the most straightforward approach is
to utilize analogous hardware for cost estimating and contacting
several industrial and/or commercial sources for cost quotations.
Two types of prices are considered here. One is a retail price
which is essentially an aftermarket selling price and the other
is a manufacturer's price equivalent (MPE). The MPE is a cost
that is representative of that incurred by a manufacturer or
charged by a vendor for a specific component or part of a
vehicle. (Lindgren has estimated this cost to be about one-
fourth to one-fifth of the retail price.(1)* For estimating
purposes within this report, a markdown factor of 0.225 is used
in going from retail to MPE cost.) The MPE is not the retail
price equivalent (RPE) of the component or part in an assembled
vehicle. However, the MPE can be used to derive an RPE by using
an appropriate markup factor, that is: MPE x Markup Factor =
RPE, where the markup factor accounts for the asembler's
corporate overhead and profit. A discussion of this markup
factor and its components can be found in (2).
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II. TURBOCHARGING
Most heavy-duty diesel engines are now turbocharged
primarily because of the increased power output turbocharging
provides. A turbocharger is a device which increases the density
of the charge air by compressing it before it enters the
combustion chamber. By forcing a greater mass of air into the
cylinder, the output of the engine can be increased since it is
proportional to the energy released by burning that particular
mass of fuel and air.
Turbocharger designs vary from one manufacturer to another,
but basically all have a compressor on one end and a turbine on
the other, supported by bearings in between. The turbine is the
device which converts the energy of the engine exhaust gases to
shaft power. Figure 1 schematically illustrates a generic turbo-
charger installation.
AIR CLEANER
Figure 1. Turbocharger Installation
Source: Maclnnes, H., Turbochargers,
H. P. Books, Tucson, Arizona (Ref.3)
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Virtually all current new model heavy-heavy duty (HHD)
trucks have turbocharged diesel engines. Therefore, the addition
of turbocharging is not an option for emission control for virtu-
ally all :HHD trucks. Turbocharging is not being applied as
universally to light and medium heavy duty (LHD and MHD) trucks
and may be added to these trucks as part of an overall strategy
for particulate control without sacrificing significant power
output.
Turbocharging an engine involves far more than the
incorporation of the turbocharger and its related hardware. Many
internal engine modifications are usually required as well.
These modifications include piston redesign, increased oil system
capacity (to spray cool the undersides of the pistons), increased
cooling system capacity, strengthened connecting rods and/or
crankshaft, redesigned exhaust valves, larger injectors, and
revised injection pump calibration. The extent of the modifica-
tions depends on the particular engine design. Some engine lines
were designed from inception to incorporate naturally aspirated
and turbocharged versions. The cost differential between natu-
rally aspirated and turbocharged versions of these engines will
understate the true cost of adding turbocharging because design
and R&D expenditures will likely be written-off over all the
engines produced. Those engines not designed from inception to
incorporate turbocharged versions will cost more to develop
turbocharged versions.
Because of the difficulty in itemizing the cost of internal
engine component design changes, and the fact that most current
engines are designed from inception to incorporate turbocharging,
the only accurate method of estimating the cost of turbocharging
is to compare complete engines. This is the approach used to
develop the rough estimate noted in Table 1.
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Table 1. Estimated Turbocharger Cost
System/
Component
Description
Estimated
Retail Price
Reference(s)
Turbocharging
a Naturally
Aspirated
Engine
Includes turbo-
charger, modified
manifolds, oil
lines, piping,
hoses, clamps, gas-
kets, modified pis-
tons, high capacity
oil system, and re-
vised injection pump
and injectors.
$1000-$3000
4,5,6
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III. ENGINE COOLANT AIR-TO-LIQUID INTERCOOLING
An intercooler, sometimes referred to as an aftercooler, is
a heat exchanger which is installed somewhere between the com-
pressor discharge of a turbocharger and the engine to cool the
inlet air (see Figure 2). By reducing the temperature of the
air, the density of the charge to the engine is increased, thus
allowing more fuel to be burned with a resultant increase in
power output. Intercooling is also a means of allowing leaner
operation which reduces peak flame temperatures and lowers NO
emissions. This may also have a beneficial effect on particulate
emissions. It also has the generally beneficial effect of
reducing the overall engine operating temperature (relative to
non-intercooled engines).
Current production air-to-liquid intercoolers use engine
coolant as the cooling medium. This limits the temperature drop
of the inlet air to some value slightly above that of the temper-
ature of the engine coolant (how much depends on the efficiency
of the intercooler). Estimated retail prices for an intercooler
which uses the engine coolant as a heat sink are provided in
Table 2.
TWWOCHAROEH
Figure 2. Turbocharged Engine with Intercooler
Source: Alpha United, Inc., El Segundo, California
(Ref. 7)
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Table 2. Estimated Costs of Engine Coolant
Air-to-Liquid Intercooling
System/
Component
Description
Manufacturer's
Price Equivalent
Reference(s)
Intercooler
Silicone
Hose
Clamps (2)
Coolant
Supply
Tubing
Intake
Manifold
Furnace-brazed core $325-$475
with headers and
fittings (assuming
$30,000 of tooling
and 2500 units/year
volume)
Six (6) inch hose $1.20
(2 three inch coup-
lings) between
turbocharger and
intake manifold
Stainless steel for $0.23
silicone hose
Six (6) foot, 5/8 $0.68
inch I.D. rubber
reinforced hose
Assumes revised $16
casting with no
increase in material
requirements.
8,9
10,11
10
12
1,13
Assumes intercooler is mounted in the intake manifold.
Incremental Cost.
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IV. SEPARATE SYSTEM AIR-TO-LIQUID INTERCOOLING
As noted in the previous section, an intercooler using the
engine coolant as the heat sink is limited in its ability to
reduce the charge temperature. A separate cooling circuit using
2 air-to-liquid heat exchangers could attain lower temperatures.
This system is the same as the system in Section III except that
the coolant flowing through the intercooler is cooled by a second
air-to-liquid heat exchanger mounted in front of the engine
radiator (see Figure 3). An external pump is required to circu-
late the coolant. The performance of this system is limited by
the temperature of the ambient air and the efficiency of the two
heat exchangers. Although such systems are not currently commer-
cially available, Table 3 provides estimated costs for components
required for such a system.
CHARGE
COOLING
AJR
PUM>
lURBOCHAROER
Figure 3. Separate Liquid Loop Intercooler System
Source: Alpha United, Inc., El Segundo, California
(Ref. 7)
8
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Table 3. Estimated Costs of Separate System
Air-to-Liquid Intercooler
System/
Component
Description
Manufacturer1s
Price Equivalent
Reference(s)
Intercooler
Furnace-brazed core
with headers and
fittings (assuming
$30,000 of tooling
and 2500 units/year
volume)
$325-$475
8,9
Silicone
Hose
Coolant
Supply
Tubing
Water Pump
Belt
Radiator
Mounting
Brackets
Misc.
Fasteners
Modified
Intake
Manifold
Six (6) inch hose (2
three inch couplings)
between turbocharger
and intake manifold
Twelve (12) foot,
5/8 inch I.D. rubber
reinforced hose
Belt-driven from
the engine
To drive water
pump
Automotive-grade
cross flow
For intercooler
water pump
Clamps, gaskets,
screws, bolts
Assumes a revised
casting with no
increase in
material requirements
$1.20 10,11
$1.40 12
$11-$17 14,15
$1.40 16
$14-$16 12
$3.60-$6.80 17
$2.30 18
$16b 1,13
Assumes intercooler is mounted in the intake manifold.
Incremental Cost.
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V. AIR-TO-AIR INTERCOOLING
Air-to-air intercoolers can also be used on turbocharged
engines. Air-to-air intercooling uses a single heat exchanger to
cool the inlet air. As depicted in Figure 4, ambient air is the
cooling medium. The intercooler is mounted in front of the truck
radiator, and the inlet air is ducted to it from the turbocharger
compressor on one side, and from it to the intake manifold on the
other side. Because only one heat exchanger is involved (the
intercooler) and the cooling medium is ambient air, this system
offers the best performance in terms of heat rejection and de-
crease in inlet air temperature. Air-to-air intercooling is fast
becoming standard on all HHD highway trucks.
The estimated costs for components required for such a
system are noted in Table 4.
CHAROE
AIR
COOLING
AIR
s1
o
o
u
5
V
TURBOCHAROER
ENOINE
WATER
PUMP
Figure 4. Air-to-Air Intercooler System
Source: Alpha United, Inc., El Segundo,
California (Ref. 7)
10
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Table 4. Estimated Costs of Air-to-Air
Intercooler
System/
Component
Description
Manufacturer's
Price Equivalent
Reference(s)
Intercooler
Steel Tubing
Silicone
Hose
Clamps
Intake
Manifold
Air-to-air furnace
brazed with headers
(assumed $25,000
for tooling and
2500 units/year
volume)
2-1/2" to 3" tubing
to go to and from
intercooler; some
45° bends
To connect steel
tubing and allow
movement between
engine and inter-
cooler; 2-1/2'
to 31
Stainless steel
clamps for silicon
hose (6-8)
Assumes a revised
casting with no
increase in material
requirements
$315-$465
$4.50-$6.80
$3.20-$3.80
8,9,19
20
10,11
$0.68-$0.90
$16C
10
1,13
Incremental Cost
11
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VI. UNIT INJECTOR FUEL INJECTION SYSTEM
All diesel engines use injection systems to meter and inject
the fuel at the appropriate time during the compression stroke.
The diesel engine requires that the fuel be injected directly
into each cylinder just before maximum cylinder compression
pressure. Because of this requirement, diesel injection systems
must be capable of generating extremely high injection pressures
relative to gasoline fuel injection systems. The following tasks
must be accomplished by all diesel injection systems:
• Meter the amount of fuel demanded by the speed of
(and load on) the engine,
• Distribute the metered fuel equally among all
cylinders,
• Inject the fuel at the correct time during the
cycle,
• Inject the fuel at the correct rate,
• Inject the fuel with the correct spray pattern and
atomization demanded by the design of the combustion
chamber, and
• Begin and end the injection sharply without
dribbling or after-injections.
The following components are necessary for diesel fuel
injection systems to perform the activities listed above:
• Pumping elements to move the fuel from the fuel tank
to the cylinder (plus associated piping, etc.),
• Metering elements to measure and supply the fuel at
the rate demanded by the speed and load,
• Metering controls to adjust the rate of the metering
elements for changes in load and speed of the en-
gine,
• Distributing elements to divide the metered fuel
equally among the cylinders,
• Timing controls to adjust the start and stop of
injection.
12
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There are many types of fuel injection systems, and they vary
from one manufacturer to another, but they all have the basic
elements listed above (in one form or another). Two such fuel
injection systems which are common for trucks and buses are the
jerk-pump system (see Section VII) and the unit injector system.
The unit injector system is used almost exclusively by
General Motors (Detroit Diesel Allison), and specifically con-
sists of the following items:
• A low pressure gear pump which is used to move the
fuel from the tank, through the fuel filter, and to
the camshaft operated unit injectors.
• The injectors which are used to meter, time, and
pressurize the fuel. The injector is operated by
the camshaft through a push rod and rocker arm
assembly. One injector is used for each cylinder<>
• The fuel filters which are used throughout the
system to protect the highly machined parts from
water and dirt.
• The governor (hydraulic or mechanical) which is
connected to the fuel control rack that controls the
position of the injection plunger.
The unit injector system is also known as the individual
pump system since this system does not have one central fuel
injection pump, and the individual injectors act as injection
pumps. While actual pressures vary with each specific design,
some systems are capable of injection pressure up to 40,000 psi.
Cost estimates for the unit injectors (only) are provided in
Table 5.
Table 5. Estimated Costs of Unit Injectors
System/
Component
Unit Injector
Description
Detroit Diesel
Allison (6 cyl. )
Detroit Diesel
Manufacturer's
Price Equivalent
$6.50 ea.
$7.20 ea.
Reference
21
21
(s)
Allison (8 cyl.)
13
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VII. HIGH PRESSURE FUEL INJECTION (JERK-PUMP) SYSTEM
As discussed in Section VI, all diesel engines use some type
of fuel injection system. One common type of fuel injection
system is the high pressure jerk-pump system. This system, as
shown schematically in Figure 5, consists of the following ele-
ments :
• The engine-driven injection pump which is used to
meter, time, pressurize, and control the fuel being
delivered to each injection nozzle,
• The governor which controls fuel delivery to
regulate the fuel delivery at each engine speed
(variable speed governor) or controls high idle and
low idle only (limiting speed type),
• High pressure steel lines which deliver the fuel
from the injection pump to the injection nozzles,
• Injection nozzles (injectors) which are used to
atomize the injected fuel, and are spring-loaded,
hydraulically operated valves inserted into the
combustion chamber (see Figure 6), and
• Fuel filters (including water traps) which are used
throughout the system to prevent damage to the
system by dirt and water.
Until recently, most jerk-pump fuel injection systems
operated at a maximum injection pressure of 10,000 psi. In the
last few years, however, injection pumps with pressures up to
15,000 psi have become the norm. While for some systems, this
has not required significant changes in the injectors or lines
(which must also withstand the high pressure) due to their ini-
tial safety factors, some injectors and lines have had to be re-
designed.
Estimated costs of both high and low pressure fuel injection
pumps and injectors appear in Table 6.
14
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Nozzle and Holder Assembly
Overflow Line
Fuel Filters
Timing Device-
Drive from Engine -fjL._
\J
Fuel-Injection Pump
Supply
Pump
Fuel Tank
Figure 5. Diesel Fuel Injection System
15
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1. Cup
2. Metering orifice
3. Plunger
4. Plug
5. O-ring seals
6. Injector spring
7. Injector link
8. Plugs
9. Stop
10. Check ball
11. Fuel out
12. Fuel in
13. Fuel screen
14. Orifice plug
15. O-ring seal
16. Cup retainer
Figure 6. Cummins Diesel Fuel Injector
Source: Goetz, W. A., et al., Methanol
Substitution and Control Technology
for a Cummins NTC Engine, presented
at the VI International Symposium on
Alcohol Fuels Technology, Ottawa,
Canada, May 21-25, 1984 (Ref. 22)
Table 6. Estimated Costs of Fuel Injection
Pumps and Injectors
System/
Component
Description
Manufacturer s
Price Equivalent Reference(s)
Fuel Pump High-Pressure Jerk- $250 (6 cyl.)
type (13,000-15,000 $320 (8 cyl.)
psi)
Lower-Pressure Jerk- $200 (6 cyl.)
type (10,000-11,000 $270 (8 cyl.)
psi)
Injection High-Pressure $5.60 ea.
Nozzles (Fuel (13,000-15,000 psi)
Injectors)
Lower-Pressure $5.60 ea.
(10,000-11,000 psi)
23
23
23
23
16
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VIII. ELECTRONIC CONTROLS
This section addresses some general components which are
likely to be used as parts of various particulate trap oxidizer
systems.: In an earlier report, cost estimates were developed for
an exhaust back pressure sensor, exhaust temperature sensor,
engine speed sensor, rack position sensor, throttle angle sensor,
and electronic control unit (24). Components for which cost
estimates were developed in this current study includes
• Engine Temperature Sensor
• Sensor/Control Wiring Harness
• Fuel Injector (including Solenoid)
• Exhaust Bypass Damper Actuator
• Air Injection Control Valve and Solenoid
Engine Temperature Sensor
The function of the engine temperature sensor is to prevent
operation of the trap regenerator until the engine is at normal
operating temperature. For example, if the engine were just
started and the back pressure sensor were to signal the need for
a regeneration cycle, the electronic control unit (ECU) would
permit the trap bypass to open but would not permit the regenera-
tion cycle to proceed until a signal is received from the engine
temperature sensor indicating that the engine temperature was
near normal.
The engine temperature sensor is usually mounted on an
accessory mounting bolt on the engine cylinder head. It is
usually a bimetallic, factory-calibrated, snap-action electrical
switch. When the set temperature is reached, the switch would
snap closed, grounding a digital circuit from the ECU.
Sensor/Control Wiring Harness
A durable wiring harness is necessary to interconnect the
various components of the trap/regenerator system. It appears
that a harness with 5-10 wires with standard automotive connec-
tors would suffice. Existing wiring harnesses for trucks cost
from $75 to $150 and involve from 15 to 40 wires. This was used
as the surrogate to estimate the wiring harness.
17
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Fuel Injector
The fuel injector is used to spray diesel fuel into the
burner assembly which is used to heat the trap to a sufficient
temperature to combust the accumulated particulate matter. This
is a light-duty, low-pressure application which can be adequately
handled by injectors typically used in automotive applications
with port-injected gasoline engines.
Exhaust Bypass Damper Actuator
When the trap is being regenerated, the exhaust flow must be
diverted around it until regeneration is completed. This system
receives an electrical signal from the ECU which actuates a
solenoid valve which in turn admits pressurized air to move a
piston or bellows which moves the bypass damper. The bypass
damper itself it not part of this subsystem but is described
later in Section IX.
Air Injection Control Valve and Solenoid
After the regeneration process is started by actuating the
exhaust bypass damper actuator, the air injection control valve
is actuated to admit air into the trap. The fuel injector also
is actuated, and the ignition system then ignites the air/fuel
mixture to begin the regeneration process. This subsystem is
composed of an electrical solenoid which is actuated by the ECU.
This bleeds pressurized air into a bellows that admits combustion
air into the burner.
Cost Estimates
The cost estimates for the components discussed above are
presented in Table 7. These estimates were developed through
direct contact with manufacturers of analogous subassemblies and
comparisons to prices of similar automotive parts in high volume
production.
18
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Table 7. Estimated Costs of Electronic Control Components
System/Component
Description
Manufacturer's
Price Equivalent
Reference(s)
Electronic Controls
Engine Temperature Sensor
Sensor/Control Wiring
Harness
Fuel Injector
(Including Solenoid)
Bimetal electric switch that
grounds and opens a logic line
for the ECU to monitor engine
operating temperature to allow
regenerator operation only after
engine warmup. Mounted to
engine block.
5-10 wires with end fittings
designed to be integrated with
the existing 12 volt vehicle
harness. Provides a wiring
assembly for electrically inter-
connecting all of the regenerator
components. Located in engine
compartment,exhaust system, and
particulate trap. External
components should be armored.
A low pressure fuel injector
similar to the type used in
gasoline fuel injection systems.
Sprays fuel into particulate
trap. Approximately 1 minute
on per 20-30 minutes of opera-
tion. Flow rate is modulated
by variation of square wave
pulses from the ECU, if
necessary. Located in upstream
area of the particulate trap.
$1.60-$2.30
25
$11-14'
12,26
$9
12
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Table 7. Estimated Costs of Electronic Control Components (Cont.)
System/Component
Description
Manufacturer's
Price Equivalent
Reference(s)
Exhaust Bypass Damper
Actuator
Air Injection Control
Valve and Solenoid
12-volt solenoid and three-way $15
air valve located at junction
between regenerator bypass pipe.
Controls the flow of pressurized
air to the bypass actuator.
12-volt solenoid and two-way $11
air valve that controls the flow
of air to the trap during
regeneration.
27
27
This is the unit cost of a separate 5-10 wire harness connecting the data acquisition
system and the various sensors and controls. The low end of the range reflects the Light
Heavy-Duty class, while the upper end of the range is representative of the Medium to
Heavy Heavy-Duty classes.
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IX. ELECTRIC REGENERATION WITH CERAMIC MONOLITH TRAP
In this section, cost and other information is provided on a
ceramic monolith particulate trap with an electrical heat regen-
eration system. As depicted in the block diagram in Figure 7,
this system captures particulates on a ceramic monolith which is
regenerated using electric resistance heaters to increase the
exhaust gas temperature high enough to combust the accumulated
particulates. Components discussed include:
• Ceramic Monolith
• Ceramic Mat
• Trap Housing
• Baffles, Flanges, and Piping
• Exhaust Bypass Valve and Piping
• Regenerator Power Supply System (Alternator,
Mounting Hardware, Batteries, Wiring Harness, Bat-
tery Box, Relays, Cable, Circuit Breakers, and
Electric Heaters)
Cost estimates are also provided for three general classes of
vehicles, namely, light-heavy duty, medium-heavy duty, and heavy-
heavy duty.
Ceramic Monolith
The particulate trap uses an extruded ceramic monolith to
filter the exhaust gases as they leave the engine. The monolith
is a matrix of alternatively open and closed cells as illustrated
in Figure 8. The cell walls are porous to allow the exhaust
gases to pass through them. Presently, the extrusion of the
monoliths is limited to sizes of about six (6) inches in diame-
ter; however, equipment to produce sizes up to 12 inches in
diameter is under development. Costs shown are based upon 12
inch diameter components.
Ceramic Mat
The monolith is securely attached to the trap body by a
surrounding ceramic mat that also cushions and insulates the
monolith. These mats are similar to those used in automotive
catalytic converters.
21
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EXHAUST
ENGINE
ALTERNATOR
I
BATTERY
RELAY
/
TRAP/HEATER
/ /
/ /
/ I
CONTROLLER
•tt
BYPASS PIPE
\
BYPASS
/
EXHAUST
GAS
Pressure
Switch
Temperature
Sensor
Figure 7. Electric Regeneration System Block Diagram
22
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ENGINE
EXHAUST
LINE
r
PARTICULATE
LADEN
EXHAUST
POROUS WALLS
V
t l\ X
* ' -V S >.
1 N s N.
TT* ' ^«- '
' s
;/
i N ^ X / -
\ f •/
,f
c\.enn
EXHAUS
— »>
PARTICULATE
BU.LO-UP
^
CERAMIC PLUGS
Figure 8. Ceramic Monolith Trap
Source: Weaver, C.S., Particulate
Control Technology and
Particulate Standards for
Heavy Duty Diesel Engines,
SAE Paper 840174 (also in
Diesel Particulate Traps,
SAE P-140, February 1984)
(Ref. 27)
Trap Housing
In general, the trap housing consists of stainless steel
tubing, flanges and entrance/exit cones, and locations for
mounting sensors and other hardware. The actual size of the
housing will depend on the particular vehicle application (i.e.,
trap volume and monolith number and size). The trap housing
would be designed so that the monolith can be easily replaced if
it should fail structurally. This is accomplished by making one
end of the trap housing removable through the use of a bolted or
clamped flanged joint arrangement.
Baffles, Flanges, and Piping
These stainless steel components are used to connect the
trap housing to the truck exhaust system and the bypass valve
assembly. An interior flange is used to support the regenerator
heater. The piping size selected was 4 inches.
Bypass- Valve and Piping
The bypass valve and piping is used to control exhaust flow
through and around the particulate trap. The bypass valve can be
23
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a butterfly type valve and is controlled by a bypass actuator
(see Section VIII).
Regenerator Power Supply System
The.regeneration of the monolith is accomplished with
controlled energy input provided by electric heating elements.
The power supply for the trap regeneration requires an on board
source of electrical power. It should be noted that heavy duty
truck electrical systems are more complex than those of light
duty vehicles. The heavy duty truck category includes vehicles
that use 12, 24 or 36 volt charging systems. The 24 and 36 volt
charging systems allow the use of additional batteries which are
used only during engine starting. These batteries are combined
in series with a simple 12 volt battery (or two - 6 volt
batteries) to provide the 24 volts or 36 volts to the engine
starter motor. The higher voltage allows the use of a smaller,
lighter-weight starter motor. It also allows greater battery
capacity to be utilized. For example, a heavy-heavy duty truck
might use a 24 volt charging system and two sets of 6 volt
batteries. This additional capacity guarantees the necessary
starting power is available during low temperature conditions.
The required 12 volts for vehicle light and accessories is
available through tapping one half of the vehicle's battery
system. Special 24/12 volt alternators are also used on medium-
heavy and heavy-heavy duty trucks. This system uses a 12 volt
alternator with an "add on" or built-in transformer-rectifier
unit. This additional unit steps up the 12 volt AC to 24 volt
AC, then converts it to 24 volts DC. The 12 volt output is
delivered to the vehicle system 12 volt battery. The
transformer-rectifier charges another 12 volt battery which is
connected in series with the system battery to provide 24 volts
to the starter motor. When the engine is running, the additional
battery system "floats on the line" and receives a low charge
rate tt> maintain its full state of charge.
With the various charging system hardware available and the
different systems configured by the many manufacturers, it is
difficult to select a system which represents a true baseline
24
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upon which to develop a cost estimate for the regenerate! power
supply system. The approach taken in this costing effort was to
assure that the required power for electrical regeneration would
be provided by an "add-on" system. This baseline approach does
not require a detailed knowledge of the specifics of each of the
existing electrical systems of the heavy duty diesel truck
classes. The "add-on" approach also results in the greatest cost
situation, since an additional alternator and a separate battery
system is required. It is very difficult to anticipate the
approach the different manufacturers will take, but it can be
safely assumed that they will attempt to integrate the
regenerator power requirements into their standard "on-board"
power systems. If this approach is properly handled for a
portion of the heavy truck classes, an on-board power system with
an upgraded alternator, an increased battery capacity (through
the use of two 6 volt batteries to replace 12 volt batteries),
and a fusible link to replace circuit breakers could substan-
tially reduce the overall system cost. The costs for this
integrated approach were also estimated to provide the lower
bound for the system cost of the electrical regeneration
approach. Descriptions of the individual components are provided
below.
Regenerator Power Supply Components - Baseline
Alternator - A standard truck alternator is driven by existing
truck engine drive pulleys. The alternator contains an internal
regulator and rectifier to supply 24 V dc to charge the batter-
ies.
Mounting Hardware - The alternator is mounted to the engine using
hardware specific to each engine. This will include mounting
brackets, flanges, pulleys and/or idlers, and belts.
Batteries - Two 12-volt batteries in series will provide storage
of energy for the resistance heating elements. A typical size
for the 3 to 7 kW power requirement is a 908-D battery (1000 cold
cranking amps and 42 minute reserve capacity).
Wiring Harness - The wiring will connect the alternator windings
to the control unit and ignition switch in the truck. This
25
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wiring will be similar to conventional truck charging system
wiring.
Battery Box - This component also will be similar to conventional
truck hardware. However, ample space will need to be allocated
to mount the batteries on the chassis.
Relays, Cable, and Circuit Breakers - The power supply to the
electric heater is controlled by an electromechanical relay
energized by the control system. Conventional truck type cables
connect the battery, relay, and circuit breakers to the heaters.
The circuit breakers protect the batteries and charging system in
the event of a short circuit.
Electric Heaters - The energy addition to the exhaust gas stream
is provided by resistance heating elements. These will be either
wound wire or ribbon elements attached to a support structure.
The heating assembly could be placed in the front of the trap
housing and secured in place by the flange. Each element will be
about 1000 watts and the number used will depend on the capacity
required.
Regenerator Power Supply Components - Integrated System
Alternator - A modified alternator with an increased amperage
rating would be used in an integrated system. This 24 volt
alternator would replace the existing 12 or 24 volt alternator.
The increase in the power rating of the alternator would have to
be sufficient to handle the additional regeneration power
requirements based on the required regeneration duty cycle. The
modified alternator system can be treated as an incremental cost
above the standard alternator.
Mounting Hardware - Since a larger alternator will be utilized,
the standard mounting hardware may require modification. The
modification should be relatively minor and can be treated as an
incremental cost.
Batteries - No change from the baseline battery system should be
necessary, except in the light-heavy duty situation where one
additional 12 volt battery could be combined with the standard 12
26
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volt battery to supply required power to the electrical resist-
ance heaters. Additional battery cables (for connecting together
the batteries) will be required in cases where additional
batteries are used.
Wiring Harness - No change.
Battery Box - One battery box and mount will be required for the
light-heavy duty class; see batteries.
Relays, Cable, and Circuit Breakers - Instead of using resettable
circuit breakers to protect the batteries and the alternator, a
fusible link may be used in the connecting cable from the
batteries to the electrical resistance heaters.
Electric Heaters - No change.
Cost Estimates
The cost estimates for the components discussed above are
presented in Table 8. These estimates were developed through
direct contact with manufacturers of analogous subassemblies and
comparisons to prices of similar automotive parts in high volume
production.
27
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Table 8. Estimated Costs of Selected Components for an Electrically Regenerated
Ceramic Monolith Trap - Baseline and Integrated Systems
System/Component
Description
Retail Price
.Estimated MPE
LHDd MHD HHDa Ref(s)
to
CD
Ceramic Monolith
Ceramic Mat
Trap Housing
Housing Baffles,
Flanges, and
Piping Connectors
Exhaust Bypass
Valve and Piping
Power Supply
System
• Alternator
• Alternator
Mounting
Hardware
Caldorite mullite
material
Insulating mat
attaching monolith
to trap housing
Stainless steel
cylindrical housing
Stainless steel
piping and flow
diverter valve
New accessory
alternator, 60-
105 amp, 24 V dc
Mounting brackets,
flanges, pulleys,
idlers, belts
$4.65/literD
(based on MPE
cost of $140/30
liter unit)
$.22/literb
(based on $7/30
liter unit)
$51C $98C $183°
$2
$19
$6
$38
$150
t$56](
$7
[$!]'
$5
$24
$7
$41
$150
[$56](
$8
t$l](
$8
$45
29
$9 30,31
$27 11,32
11
32,33
$160°
l$60]
$9
[$1.50]'
17,34
17
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Table 8. Estimated Costs of Selected Components for an Electrically Regenerated
Ceramic Monolith Trap - Baseline and Integrated Systems (Cont.)
System/Component
Description
Retail Price
LHD
Estimated MPE
1 MHD
HHD Ref(s)
VO
Power Supply System
© Batteries
Wiring
Harness
Battery Box
• Relay -
low amp
• Cable
Cable
• Circuit
Breaker
® Fusible Link
Electric
Heater (with
mounting hdw.)
(cont.)
12 volt, heavy duty; $170/unit
one for LHD and two
for MHD and HHD
Alternator wiring $25
to battery and cab
Container and
mounting hardware
Heavy duty, 24 V dc, $15/unit
600 amp rating
#2 gage, from
battery to relays
$38d'S $77d'e $77d'e 17,33
#2 gage, from
relays to heaters
Heater protection;
fused disconnect,
circuit breaker, or
timer; 50 amp
Circuit protection,
replaces circuit
breaker
$3/unit
$6.50/unit
Wound wire or $4/unit
ribbon type;
3-7 kW
$5.60d'e $5.60d'6 $5.60dfG
$9d,e $1Qd,e $nd,e
$10d'e'f $17d'e'g $24d'e'h
$2.30d $2.50d $2.70d
$0.75/unit $0.60e'f $1.00e'g $1.40e'h
34
34
34
34
$2.00d $3.40d $4.70d 34
$4.50d'f $7.40d'g $10d'h 35
$2
.70d'e'f $4.50d'e'g $6.30d'e'h 36
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Table 80 Estimated Costs of Selected Components for an Electrically Regenerated
Ceramic Monolith Trap - Baseline and Integrated Systems (Cont.)
System/Component
Description
Retail Price
Estimated MPE
LHDa MHD HHDa Ref(s)
Exhaust Back
Pressure Sensor
Low voltage,
pressure activated
switch
$60/unit
$13
$13
$13 1,37,38
U)
o
Exhaust Temp-
erature Sensor
Controller
Control Wiring
Heavy-duty thermo- $20/unit
couple
High temperature $120/unit
or temperature rise,
high pressure
activated controller
for heater relay and
bypass valve actuator
Sensors, actuator, $25
relay, and con-
troller wiring
$4.00 $4.00 $4.00
$27
$27
$27
39
40
$5.60 $5.60 $5.60 11,32
rLHD - light heavy duty; MHD - medium heavy duty; HHD - heavy heavy duty.
MPE Price
^Cost dependent on size. Assumed 11 liters for LHD, 21 liters for MHD, and 39 liters for HHD.
Baseline System
^Integrated System
3-1000 kW units
JJ5-1000 kW units
7-1000 kW units
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X. CATALYTIC MATERIAL
In an earlier report (24), cost estimates were provided for
a number of components associated with a ceramic fiber trap metal
catalyst: which is illustrated in Figure 9. In this current
study, the cost of the catalytic material, copper chloride, was
estimated. In bulk quantities (>24,000 Ib in 300 Ib. fiber
drums), copper chloride can be obtained for approximately
$1.16/lb (41). Repackaging costs (e.g., 50 Ib fiber drums) can
add another $0.10/lb to the bulk cost. For small orders (<4,000
Ib), the cost increases to approximately $1.46/lb in 300 Ib
drums.
For the system considered here, it was assumed that the
units produced would consist of a throw-away container approxi-
mately six tenths of a gallon in size. Such a container would
contain approximately 12 Ib. of copper chloride. Assuming a cost
of approximately $5 for a structural plastic throwaway container,
the estimated cost can be calculated as:
12 Ib. x $1.46/lb. + $5.00 = $22.52
Table 9. Estimated Cost of Catalytic Material
System/
Component
Catalytic
Material
Manufacturer ' s
Description Price Equivalent
Reference (s)
Solid Catalyst
Plus Container
Solid catalyst
(copper chloride)
is produced in a
sealed 1-gallon
throwaway plastic
container. Solid
catalyst is sprayed
into the trap during
regeneration to
reduce the particu-
late combustion
temperature.
Located at rear of
tractor, near the
trap.
$5oOO
41
31
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Filter Outlet
Temp. Sensor
Silica Fiber
Trap
Crank Pulley or
Flywheel
Compressed Air
Line to Catalyst
Fluidiser/Injector
(Uses Existing Vehicle
Compressed Air System)
Engine Speed Sensor
Figure 9. Ceramic Fiber Trap Metal Catalyst
Source: Ref. 24
32
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XI. BURNER HOUSING AND IGNITION SYSTEM
In an earlier report (24), cost estimates were provided for
several components (fuel injector, fuel pump and combustion air
blower) associated with a diesel fuel burner regeneration system.
This system is illustrated schematically in Figure 10. Two
additional components for which cost estimates were developed in
this current study are a burner can and ignition system.
Burner Can
The burner can is designed to hold the flame of the fuel
burner and to direct the flames and heated air into the trap.
Since it is subject to relatively high temperatures (>1200 F),
materials used largely are made of a high-grade stainless steel
for strength, corrosion resistance, and long life. Heat output
necessary for reliable ignition of the trap is approximately
100,000 Btu/hr.
Ignition System
A continuous spark is necessary to initiate and maintain
combustion in the regenerator burner can during the regeneration
cycle. A high-voltage (12 kV+) AC power is needed. Also, a
flame sensor and sensor relay are necessary to assure that igni-
tion has occurred. Otherwise, the ECU must cut off the fuel flow
to the burner.
Cost Estimates
The cost estimates for the two components noted above are
presented in Table 10.
33
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Trap Outlet Teat> Sensor
Bypass Muffler
Paniculate
Trap
Bypass Piping
AP Sensor
Hot Wire
to Burner
Air Solenoid
Valve
Fuel reed line
to Burner Injector
Bypass
Damper
Actuator
r_
Hat Wire
to Utay
Solenoid
Valve (Cont-
rol! Air to
Bypass Daaper)-
L— Hot Hire to
Burner Fuel Feed
Solenoid Valve
Injection Pump
Fuel Injection Line,
(Typical)
Crank Pulley
Figure 10. Diesel Fuel Burner Regeneration System
Schematic Diagram
Source: Ref. 24
34
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Table 10. Estimated Costs of Burner Can and Ignition System
for Diesel Fuel Burner Regeneration System
System/
Component
Description
Manufacturer's
Price Equivalent Reference(s)
Burner Housing
and Ignition
System
Burner Can
Ignition System
Outer steel tube— $16
4-6 inches in
diameter, 24 inches
long. Inner stain-
less steel flame
holder, various
heat shields.
Provides an enclosed
space for the mixing
of air and fuel and
subsequent ignition
and combustion.
Located upstream of
trap.
Inverter, transformer, $34
electrode, flame
sensor, and sensor
relay. Provides
spark ignition and
flame control for
the burner. Located
at rear of tractor.
37
37
35
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XII. REFERENCES/SOURCES OF INFORMATION
1. Lindgren, L. H., Cost Estimations for Emission Control
Related Components'/Systems and Cost Methodology Description,
EPA 460/3-78-002, prepared for U.S.Environmental Protection
Agency, December 1977.
2. Putman, Hayes & Bartlett, Inc., Report on EPA's Retail Price
Equivalent Methodology, Memorandum to Will Smith, Economic
Analysis Division, U.S. Environmental Protection Agency,
September 28, 1984.
3. Maclnnes, H., Turbochargers, H. P. Books, Tucson, Arizona,
1976.
4. Albin Engine Power (Caterpillar Engine Dealer), Elkridge,
Maryland, telephone conversation, January 9, 1985.
5. Johnson & Towers Baltimore, Inc. (Detroit Diesel Allison
Engine Dealer), Baltimore, Maryland, telephone conversation,
January 10, 1985.
6. Cummins Mid-Atlantic, Inc. (Cummins Engine Dealer),
Baltimore, Maryland, telephone conversation, January 24,
1985.
7. Intercooling Turbocharged Engines, Alpha United, Inc., 1983
Brochure,El Segundo,California.
8. Alpha United, Inc. (Intercooler Manufacturer), El Segundo,
California, telephone conversation, January 9, 1985.
9. Modine Manufacturing Co. (Intercooler Manufacturer), Racine,
Wisconsin, telephone conversation, January 9, 1985.
10. M & J Associates (Industrial Supplier), Baltimore, Maryland,
telephone conversation, January 11, 1985.
11. Scheiber Automotive, Inc. (Truck Parts Supplier), Baltimore,
Maryland, telephone conversation, January 11, 1985.
12. J. C. Whitney & Co., Chicago, Illinois, Automotive Parts and
Accessories Catalog, 1984.
13. Ir_o_n Castings Handbook, Iron Castings Society, Inc., 1981.
14. 40-West Volkswagen, Inc., Baltimore, Maryland, telephone
conversation, January 11, 1985.
15. Nationwide AMC Jeep Renault, Baltimore, Maryland, telephone
conversation, January 11, 1985.
16. Grainger's, Chicago, Illinois, Wholesale Net Price Motorbook
Catalog No. 363, Spring 1983.
36
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17. Wayne Manock, President, Manock's Services, Annapolis,
Maryland, telephone conversation, January 16, 1985.
18. Engineering estimate based on miscellaneous fasteners used
on heavy-duty trucks.
19. Russ Rhoades, Mack Truck, Harrisburg, Pennsylvania,
telephone conversation, January 17, 1985.
20. Means Electrical Cost Data, Kingston, Massachusetts, 1984.
21. Johnson & Towers Baltimore, Inc., Detroit Diesel Allison
Authorized Distributor, Baltimore, Maryland, telephone
conversation, February 4, 1985.
22. Goetz, W. A., et al., Methanol Substitution and Control
Technology for a Cummins NTC Engine, presented at the VI
International Symposium on Alcohol Fuels Technology, Ottawa,
Canada, May 21-25, 1984.
23. Jack O'Donnell, American Bosch, Division of United
Technologies Corporation, Springfield, Massachusetts, Janu-
ary, 1985.
24. Mueller Associates, Inc., Cost of Selected Trap-Oxidizer
System Components for Heavy-Duty Vehicles, prepared for the
U.S.Environmental Protection Agency,September 28, 1984.
25. Chrysler Corporation dealer, Baltimore, Maryland, telephone
conversation, January 1985.
26. International Harvester (IH) dealer, Baltimore, Maryland,
telephone conversation, January 1985.
27. Automatic Switch Co., Florham Park, New Jersey, Solenoid
Valve Catalog.
28. Weaver, C. S., Particulate Control Technology and
Particulate Standards for Heavy Duty Diesel Engines, SAE
Paper 840174 (also in Diesel Particulate Traps, SAE P-140,
February 1984).
29. Jim Gibson, Project manager, Manufacturing, Corning Glass
Works, Corning, New York, telephone conversation, January
4, 1985.
30. Suresh Gulati, Research Scientist, Corning R&D Laboratories,
Corning, New York, telephone conversation, January 4, 1985.
31. Richard Merry, Senior Product Development Engineer,
Materials Department/3M, St. Paul, Minnesota, telephone
conversation, February 4, 1985.
37
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32. International Harvester, Baltimore, Maryland, telephone
conversation, January 1985.
33. Sears, Roebuck and Co., Automotive Catalog, 1984.
34. Vince Chesis, Parts Manager, Automotive Electric & Parts
Co., Baltimore, Maryland, telephone conversation, January 9,
1985.
35. Bill Wright, Sales Engineer, Airpax, North American Phillips
Controls Co., Cambridge, Maryland, telephone conversation,
January 16, 1985.
36. David Kangas, Manager Product Development, Hartford
Eichenaurer, Newport, New Hampshire, telephone conversation,
January 16, 1985.
37. R. E. Michel Company, Inc. (Industrial Products Supplier),
1983 Catalog, Baltimore, Maryland.
38. Mark Winters, Belfab Corporation, Daytona Beach, Florida,
telephone conversation, September 24, 1984.
39. Telephone conversation with local automotive and truck parts
vendors (Volkswagen, Saab, GM, Ford) in local Baltimore-
Washington, D.C. area.
40. Berry Philips, Metro Byte Corporation, Stroughton,
Massachusetts, telephone conversation, January 17, 1985.
41. Chemetals, Incorporated, Baltimore, Maryland, telephone
conversation, January 1985.
38
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