[Federal Register Volume 86, Number 182 (Thursday, September 23, 2021)]
[Rules and Regulations]
[Pages 52833-52837]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: C1-2021-05306]
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ENVIRONMENTAL PROTECTION AGENCY
40 CFR Parts 9, 59, 60, 85, 86, 88, 89, 90, 91, 92, 94, 1027, 1033,
1036, 1037, 1039, 1042, 1043, 1045, 1048, 1051, 1054, 1060, 1065,
1066, 1068, and 1074
[EPA-HQ-OAR-2019-0307; FRL-10018-52-OAR]
RIN 2060-AU62
Improvements for Heavy-Duty Engine and Vehicle Test Procedures,
and Other Technical Amendments
Correction
In rule document 2021-05306, appearing on pages 34308-34590, in the
issue of Tuesday, June 29, 2021, make the following corrections:
Sec. 1037.565 [Corrected]
0
1. On page 34486, beginning in the first column, Section 1037.565 is
corrected to read as follows:
1037.565 Transmission efficiency test.
This section describes a procedure for mapping transmission
efficiency through a determination of transmission power loss.
(a) You may establish transmission power loss maps based on testing
any number of transmission configurations within a transmission family
as specified in Sec. 1037.232. You may share data across any
configurations within the family, as long as you test the transmission
configuration with the lowest efficiency from the transmission family.
Alternatively, you may ask us to approve analytically derived power
loss maps for untested configurations within the same transmission
family (see Sec. 1037.235(h)).
(b) Prepare a transmission for testing as follows:
(1) Select a transmission with less than 500 hours of operation
before testing.
(2) Mount the transmission to the dynamometer such that the geared
shaft in the transmission is aligned with the input shaft from the
dynamometer.
(3) Add transmission oil according to the transmission
manufacturer's instructions. If the transmission manufacturer specifies
multiple transmission oils, select the one with the highest viscosity
at operating temperature. You may use a lower-viscosity transmission
oil if we approve it as critical emission-related maintenance under
Sec. 1037.125. Fill the transmission oil to a level that represents
in-use operation. You may use an external transmission oil conditioning
system, as long as it does not affect measured values.
(4) Include any internal and external pumps for hydraulic fluid and
lubricating oil in the test. Determine the work required to drive an
external pump according to 40 CFR 1065.210.
(5) Install equipment for measuring the bulk temperature of the
transmission oil in the oil sump or a similar location.
(6) If the transmission is equipped with a torque converter, lock
it for all testing performed in this section.
(7) Break in the transmission using good engineering judgment.
Maintain transmission oil temperature at (87 to 93) [deg]C for
automatic transmissions and transmissions having more than two friction
clutches, and at (77 to 83) [deg]C for all other transmissions. You may
ask us to approve a different range of transmission oil temperatures if
you have data showing that it better represents in-use operation.
(c) Measure input and output shaft speed and torque as described in
40 CFR 1065.210(b). You must use a speed measurement system that meets
an accuracy of 0.05% of point. Accuracy requirements for
torque transducers depend on the highest loaded transmission input and
output torque as described in paragraph (d)(2) of this section. Use
torque transducers for torque input measurements that meet an accuracy
requirement of 0.2% of the highest loaded transmission
input for loaded test points and 0.1% of the highest loaded
transmission input torque for unloaded test points. For torque output
measurements, torque transducers must meet an accuracy requirement of
0.2% of the highest loaded transmission output torque for
each gear ratio. Calibrate and verify measurement instruments according
to 40 CFR part 1065, subpart D. Command speed and torque at a minimum
of 10 Hz, and record all data, including bulk oil temperature, at a
minimum of 1 Hz mean values.
(d) Test the transmission at input shaft speeds and torque
setpoints as described in this paragraph (d). You may exclude lower
gears from testing; however, you must test all the gears above the
highest excluded gear. GEM will use default values for any untested
gears. The test matrix consists of test points representing
transmission input shaft speeds and torque setpoints meeting the
following specifications for each tested gear:
[[Page 52834]]
(1) Test at the following transmission input shaft speeds:
(i) 600.0 r/min or transmission input shaft speed when paired with
the engine operating at idle.
(ii) The transmission's maximum rated input shaft speed. You may
alternatively select a value representing the highest expected in-use
transmission input shaft speed.
(iii) Three equally spaced intermediate speeds. The intermediate
speed points may be adjusted to the nearest 50 or 100 r/min. You may
test any number of additional speed setpoints to improve accuracy.
(2) Test at certain transmission input torque setpoints as follows:
(i) Include one unloaded (zero-torque) setpoint.
(ii) Include one loaded torque setpoint between 75% and 105% of the
transmission's maximum rated input shaft torque. However, you may use a
lower torque setpoint as needed to avoid exceeding dynamometer torque
limits, as long as testing accurately represents in-use performance. If
your loaded torque setpoint is below 75% of the transmission's maximum
rated input shaft torque, you must demonstrate that the sum of time for
all gears where demanded engine torque is between your maximum torque
setpoint and 75% of the transmission's maximum rated input shaft torque
is no more than 10% of the time for each vehicle drive cycle specified
in subpart F of this part. This demonstration must be made available
upon request.
(iii) You may test at any number of additional torque setpoints to
improve accuracy.
(iv) Note that GEM calculates power loss between tested or default
values by linear interpolation, except that GEM may extrapolate outside
of measured values to account for testing at torque setpoints below 75%
as specified in paragraph (d)(2)(ii) of this section.
(3) In the case of transmissions that automatically go into neutral
when the vehicle is stopped, also perform tests at 600 r/min and 800 r/
min with the transmission in neutral and the transmission output fixed
at zero speed.
(e) Determine transmission efficiency using the following
procedure:
(1) Maintain ambient temperature between (15 and 35) [deg]C
throughout testing. Measure ambient temperature within 1.0 m of the
transmission.
(2) Maintain transmission oil temperature as described in paragraph
(b)(7) of this section.
(3) Use good engineering judgment to warm up the transmission
according to the transmission manufacturer's specifications.
(4) Perform unloaded transmission tests by disconnecting the
transmission output shaft from the dynamometer and letting it rotate
freely. If the transmission adjusts pump pressure based on whether the
vehicle is moving or stopped, set up the transmission for unloaded
tests to operate as if the vehicle is moving.
(5) For transmissions that have multiple configurations for a given
gear ratio, such as dual-clutch transmissions that can pre-select an
upshift or downshift, set the transmission to operate in the
configuration with the greatest power loss. Alternatively, test in each
configuration and use good engineering judgment to calculate a weighted
power loss for each test point under this section based on field data
that characterizes the degree of in-use operation in each
configuration.
(6) For a selected gear, operate the transmission at one of the
test points from paragraph (d) of this section for at least 10 seconds.
Measure the speed and torque of the input and output shafts for at
least 10 seconds. You may omit measurement of output shaft speeds if
your transmission is configured to not allow slip. Calculate arithmetic
mean values for mean input shaft torque, Tin, mean output
shaft torque, Tout, mean input shaft speed, fnin,
and mean output shaft speed, fnout, for each point in the
test matrix for each test. Repeat this stabilization, measurement, and
calculation for the other speed and torque setpoints from the test
matrix for the selected gear in any sequence. Calculate power loss as
described in paragraph (f) of this section based on mean speed and
torque values at each test point.
(7) Repeat the procedure described in paragraph (e)(6) of this
section for all gears, or for all gears down to a selected gear. This
section refers to an ``operating condition'' to represent operation at
a test point in a specific gear.
(8) Perform the test sequence described in paragraphs (e)(6) and
(7) of this section three times. You may do this repeat testing at any
given test point before you perform measurements for the whole test
matrix. Remove torque from the transmission input shaft and bring the
transmission to a complete stop before each repeat measurement.
(9) You may need to perform additional testing at a given operating
condition based on a calculation of a confidence interval to represent
repeatability at a 95% confidence level at that operating condition. If
the confidence interval is greater than 0.10% for loaded tests or
greater than 0.05% for unloaded tests, perform another measurement at
that operating condition and recalculate the repeatability for the
whole set of test results. Continue testing until the confidence
interval is at or below the specified values for all operating
conditions. As an alternative, for any operating condition that does
not meet this repeatability criterion, you may determine a maximum
power loss instead of calculating a mean power loss as described in
paragraph (g) of this section. Calculate a confidence interval
representing the repeatability in establishing a 95% confidence level
using the following equation:
[GRAPHIC] [TIFF OMITTED] TR23SE21.000
Where:
[sigma]Ploss = standard deviation of power loss values at
a given operating condition (see 40 CFR 1065.602(c)).
N = number of repeat tests for an operating condition.
Prated = the transmission's rated input power for a given
gear. For testing in neutral, use the value of Prated for
the top gear.
Example:
[sigma]Ploss = 0.1200 kW
N = 3
Prated = 314.2000 kW
[[Page 52835]]
[GRAPHIC] [TIFF OMITTED] TR23SE21.001
Confidence Interval = 0.0432%
(f) Calculate the mean power Ploss, at each operating
condition as follows:
(1) Calculate Ploss for each measurement at each
operating condition as follows:
[GRAPHIC] [TIFF OMITTED] TR23SE21.008
Where:
Tin = mean input shaft torque from paragraph (e)(6) of
this section.
fnin = mean input shaft speed from paragraph (e)(6) of
this section in rad/s.
Tout = mean output shaft torque from paragraph (e)(6) of
this section. Let Tout = 0 for all unloaded tests.
fnout = mean output shaft speed from paragraph (e)(6) of
this section in rad/s. Let fnout = 0 for all tests with
the transmission in neutral. See paragraph (f)(2) of this section
for calculating fnout as a function of fnin
instead of measuring fnout.
(2) For transmissions that are configured to not allow slip, you
may calculate fnout based on the gear ratio using the
following equation:
[GRAPHIC] [TIFF OMITTED] TR23SE21.002
Where:
kg = transmission gear ratio, expressed to at least the
nearest 0.001.
(3) Calculate Ploss as the mean power loss from all
measurements at a given operating condition.
(4) The following example illustrates a calculation of
Ploss:
Tin,1 = 1000.0 N[middot]m
fnin,1 = 1000 r/min = 104.72 rad/sec
Tout,1 = 2654.5 N[middot]m
fnout,1 = 361.27 r/min = 37.832 rad/s
Ploss,1 = 1000.0[middot]104.72-2654.5[middot]37.832
Ploss,1 = 4295 W = 4.295 kW
Ploss,2 = 4285 W = 4.285 kW
Ploss,3 = 4292 W = 4.292 kW
[GRAPHIC] [TIFF OMITTED] TR23SE21.003
(g) Create a table with the mean power loss, Ploss,
corresponding to each operating condition for input into GEM. Also
include power loss in neutral for each tested engine's speed, if
applicable. Express transmission input speed in r/min to one decimal
place; express input torque in N[middot]m to two decimal places;
express power loss in kW to four decimal places. Record the following
values:
[GRAPHIC] [TIFF OMITTED] TR23SE21.009
(2) For any operating condition not meeting the repeatability
criterion in paragraph (e)(9) of this section, record the maximum value
of Ploss for that operating condition along with the
corresponding values of Tin and fnin.
(h) Record declared power loss values at or above the corresponding
value calculated in paragraph (f) of this section. Use good engineering
judgment to select values that will be at or above the mean power loss
values for your production transmissions. Vehicle manufacturers will
use these declared mean power loss values for certification.
Sec. 1037.570 [Corrected]
0
2. On page 34488, beginning in the first column, Section 1037.570 is
corrected to read as follows:
Sec. 1037.570 Procedures to characterize torque converters.
GEM includes input values related to torque converters. This
section describes a procedure for mapping a torque converter's capacity
factors and torque ratios over a range of operating conditions. You may
ask us to approve analytically derived input values based on this
testing for additional untested configurations as described in Sec.
1037.235(h).
(a) Prepare a torque converter for testing as follows:
(1) Select a torque converter with less than 500 hours of operation
before the start of testing.
(2) If the torque converter has a locking feature, unlock it for
all testing performed under this section. If the torque converter has a
slipping lockup clutch, you may ask us to approve a different strategy
based on data showing that it represents better in-use operation.
(3) Mount the torque converter with a transmission to the
dynamometer in series or parallel arrangement or mount the torque
converter without a transmission to represent a series configuration.
(4) Add transmission oil according to the torque converter
manufacturer's
[[Page 52836]]
instructions, with the following additional specifications:
(i) If the torque converter manufacturer specifies multiple
transmission oils, select the one with the highest viscosity at
operating temperature. You may use a lower-viscosity transmission oil
if we approve that as critical emission-related maintenance under Sec.
1037.125.
(ii) Fill the transmission oil to a level that represents in-use
operation. If you are testing the torque converter without the
transmission, keep output pressure and the flow rate of transmission
oil into the torque converter within the torque converter
manufacturer's limits.
(iii) You may use an external transmission oil conditioning system,
as long as it does not affect measured values.
(5) Install equipment for measuring the bulk temperature of the
transmission oil in the oil sump or a similar location and at the
torque converter inlet. If the torque converter is tested without a
transmission, measure the oil temperature at the torque converter
inlet.
(6) Break in the torque converter and transmission (if applicable)
using good engineering judgment. Maintain transmission oil temperature
at (87 to 93) [deg]C. You may ask us to approve a different range of
transmission oil temperatures if you have data showing that it better
represents in-use operation.
(b) Measure pump and turbine shaft speed and torque as described in
40 CFR 1065.210(b). You must use a speed measurement system that meets
an accuracy of 0.1% of point or 1 r/min,
whichever is greater. Use torque transducers that meet an accuracy of
1.0% of the torque converter's maximum rated input and
output torque, respectively. Calibrate and verify measurement
instruments according to 40 CFR part 1065, subpart D. Command speed and
torque at a minimum of 10 Hz. Record all speed and torque data at a
minimum of 1 Hz mean values. Note that this section relies on the
convention of describing the input shaft as the pump and the output
shaft as the turbine shaft.
(c) Determine torque converter characteristics based on a test
matrix using either constant input speed or constant input torque as
follows:
(1) Constant input speed. Test at constant input speed as follows:
(i) Select a fixed pump speed, [fnof]npum, between (1000
and 2000) r/min.
(ii) Test the torque converter at multiple speed ratios, v, in the
range of v = 0.00 to v = 0.95. Use a step width of 0.10 for the range
of v = 0.00 to 0.60 and 0.05 for the range of v = 0.60 to 0.95.
Calculate speed ratio, v, as turbine shaft speed divided by pump speed.
(2) Constant input torque. Test at constant input torque as
follows:
(i) Set the pump torque, Tpum, to a fixed positive value
at [fnof]npum = 1000 r/min with the torque converter's
turbine shaft locked in a non-rotating state (i.e., turbine's speed,
ntur, = 0 r/min).
(ii) Test the torque converter at multiple speed ratios, v, in the
range of v = 0.00 up to a value of [fnof]ntur that covers
the usable range of v. Use a step width of 0.10 for the range of v =
0.00 to 0.60 and 0.05 for the range of v = 0.60 to 0.95.
(3) You may limit the maximum speed ratio to a value below 0.95 if
you have data showing this better represents in-use operation. You must
use the step widths defined in paragraph (c)(1) or (2) of this section
and include the upper limit as a test point. If you choose a value less
than 0.60, you must test at least seven evenly distributed points
between v = 0 and your new upper speed ratio.
(d) Characterize the torque converter using the following
procedure:
(1) Maintain ambient temperature between (15 and 35) [deg]C
throughout testing. Measure ambient temperature within 1.0 m of the
torque converter.
(2) Maintain transmission oil temperature as described in paragraph
(a)(6) of this section. You may use an external transmission oil
conditioning system, as long as it does not affect measured values.
(3) Use good engineering judgment to warm up the torque converter
according to the torque converter manufacturer's specifications.
(4) Test the torque converter at constant input speed or constant
input torque as described in paragraph (c) of this section. Operate the
torque converter at v = 0.00 for (5 to 60) seconds, then measure pump
torque, turbine shaft torque, angular pump speed, angular turbine shaft
speed, and the transmission oil temperature at the torque converter
inlet for (5 to 15) seconds. Calculate arithmetic mean values for pump
torque, Tpum, turbine shaft torque, Ttur, angular
pump speed, fnpum, and angular turbine shaft speed,
fntur, over the measurement period. Repeat this
stabilization, measurement, and calculation for the other speed ratios
from the test matrix in order of increasing speed ratio. Adjust the
speed ratio by increasing the angular turbine shaft speed.
(5) Complete a test run by performing the test sequence described
in paragraph (d)(4) of this section two times.
(6) Invalidate the test run if the difference between the pair of
mean torque values for the repeat tests at any test point differ by
more than 1 N[middot]m or by more than 5% of
the average of those two values. This paragraph (d)(6) applies
separately for mean pump torque and mean turbine shaft torque at each
test point.
(7) Invalidate the test run if any calculated value for mean
angular pump speed does not stay within 5 r/min of the
speed setpoint or if any calculated value for mean pump torque does not
stay within 5 N[middot]m of the torque setpoint.
(e) Calculate the mean torque ratio, l, at each tested speed ratio,
v, as follows:
(1) Calculate at each tested speed ratio as follows:
[GRAPHIC] [TIFF OMITTED] TR23SE21.004
Where:
Ttur = mean turbine shaft torque from paragraph (d)(4) of
this section.
Tpum = mean pump torque from paragraph (d)(4) of this
section.
(2) Calculate l as the average of the two values of l at each
tested speed ratio.
(3) The following example illustrates a calculation of l:
Ttur,v=0,1 = 332.4 N[middot]m
Tpum,v=0,1 = 150.8 N[middot]m
Ttur,v=0,2 = 333.6 N[middot]m
Tpum,v=0,2 = 150.3 N[middot]m
[GRAPHIC] [TIFF OMITTED] TR23SE21.005
(f) Calculate the mean capacity factor, k, at each tested speed
ratio, v, as follows:
(1) Calculate K at each tested speed ratio as follows:
[GRAPHIC] [TIFF OMITTED] TR23SE21.006
Where:
fnpum = mean angular pump speed from paragraph (d)(4) of
this section.
Tpum = mean pump torque from paragraph (d)(4) of this
section.
[[Page 52837]]
(2) Calculate k as the average of the two values of K at each
tested speed ratio.
(3) The following example illustrates a calculation of k:
fnpum,v=0,1 = fnpum,v=0,2 = 1000.0 r/min
Tpum,v=0,1 = 150.8 N[middot]m
[GRAPHIC] [TIFF OMITTED] TR23SE21.007
(g) Create a table of GEM inputs showing l and k at each tested
speed ratio, v. Express l to two decimal places; express k to one
decimal place; express v to two decimal places.
[FR Doc. C1-2021-05306 Filed 9-22-21; 8:45 am]
BILLING CODE 0099-10-D