Document ID: EPA_FRDOC_0001-27340
Agency: epa
Document Type: Rule
Title: Improvements for Heavy-Duty Engine and Vehicle Test Procedures, and other Technical Amendments
Posted Date: 2021-09-23T04:00Z

[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