Gilson HM-382 User manual

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INTRODUCTION
The Gilson model HM-382 Digital Pneumatic Direct
Shear Machine is a tabletop unit that provides direct or
direct/residual shear values for evaluating the strength
and stability of soils. This device utilizes a pneumatic
loading piston for applying the vertical load to the sam-
ple. A calibration chart is included for setting the high
load or the low load via the Fairchild Regulator while a
built-in digital readout displays the vertical load in psi.
This Direct/Residual Shear Device has a strain rate
of 0.0001 – 0.3 in/min (0.0025 – 7.62 mm/min) with a
maximum shear displacement of 0.8in (20.3mm) and
the travel speed is set with the thumbwheels on the left
side of the unit. The residual shear force is determined
by a load cell and while real time load settings and
peak load are displayed on the digital readout. Con-
solidation and shear displacement are measured with
Displacement transducers and displayed on a digital
readout.
FEATURES
• Total shear capacity of 1,500lbf (6.67kN)
• Stepper motor controls strain rates to +/- 1% from
0.0001 – 0.3in/min (0.0025 – 7.62mm/min
• Teoncoatedanodized aluminumwater chamber
with drainage port included.
• Meets requirements for ASTM D3080 and
AASHTO T 236
REQUIRED ACCESSORIES (purchased separately)
• Direct shear boxes are sold separately and are
available in a wide range of inch and metric sizes
with round or square shapes. See all options at
www.gloabalgilson.com and in chart below.
Direct Shear Boxes & Accessories
Description Shear Box Cutters Extruders
Porous
Stones
Round Direct Shear Boxes
50mm (1.97in) Diameter
2.0in (50.8mm) Diameter
60mm (2.36in) Diameter
2.42in (61.4mm) Diameter
2.5in (63.5mm) Diameter
100mm (3.94in) Diameter
4in (101.6mm) Diameter
HMA733M
HMA733
HMA734M
HMA734
HMA735
HMA737
HMA736
HMA743M
HMA743
HMA744M
HMA744
HMA745
HMA747
HMA746
HMA763M
HMA763
HMA764M
HMA764
HMA765
HMA767
HMA766
GSA208
GSA210
GSA213
GSA217
GSA219
GSA231
GSA232
Square Direct Shear Boxes
50mm (1.97in) Square
2.0in (50.8mm) Square
60mm (2.36in) Square
2.42in (61.4mm) Square
2.5in (63.5mm) Square
100mm (3.94in) Square
4in (101.6mm) Square
HMA733MS
HMA733S
HMA734MS
HMA734SA
HMA735S
HMA737S
HMA736S
HMA743MS
HMA743S
HMA744MS
HMA744SA
HMA745S
HMA747S
HMA746S
HMA763MS
HMA763S
HMA764MS
HMA764SA
HMA765S
HMA767S
HMA766S
GSA208S
GSA210S
GSA213S
GSA217S
GSA219S
GSA231S
GSA232S
• A constant supply of compressed air at 90psi
(6.2 bar) is required for use.
• A computer or laptop for connecting to the data
readout.
UNPACKING & SETUP
• Inspect your Direct/Residual Shear Machine for
damage, remove from the pallet.
• Place Direct Shear Machine on a sturdy, level sur-
face, such as a bench top or Model HMA-95 Rolling
Cart for Shear Machines.
• Review the Connections section and install neces-
sary components.
HM-382 & HM-382F Digital Pneumatic Direct
Shear Machine
OPERATING MANUAL
Rev: 2/2021
PHONE: [phone] P.O. Box 200, Lewis Center, Ohio 43035-0200
740-548-7298 E-mail: [e-mail] Product Web Page: www.globalgilson.com
FAX: [phone]
740-548-5314
HM-382

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CONNECTIONS
Vertical Displacement Transducer Rod – Screws
into the top platform to the right of the rear pull-down
rod.
Vertical Displacement Transducer Clamping Arm –
Attach to the above rod.
Vertical Displacement Transducer – Consolidation –
Attach to the clamping arm with the screw provided.
Connection is made at the rear of the readout box.
Horizontal Displacement Transducer – Shear – At-
tach to the threaded rod on the angle bracket-top plat-
form, right front. Connection is made at the rear of the
readout box.
Air Line – A constant supply of clean, dry air is re-
quired. The air inlet air pressure should not exceed 200
psi, nor should it ever be less than 20 psi higher than
the highest pressure setting. The connection is a ¼”
Swagelok, located in the rear of the cabinet. Insert the
tubingintothettinguntilitbottomsout.Withthenut
ngertight,tightenthetting1¼turnswithawrench.
Do not over tighten.
Pressure Transducer – The internal pressure trans-
ducer measures the output of the pneumatic loading
system. The external wire that is at the back of the di-
rect shear unit is plugged into channel four of the Data
Readout system.
Load Cell – Connect the load cell to the support cast-
ing at the right end of the direct shear using the two
knobs. Adjust the knobs so that the load cell is as far
to the right as possible. This will allow room for assem-
bling the water chamber and the shear rings with min-
imum interference. Connection is made at the rear of
the readout box.
Mini USB 2.0 Port – Connection is made at the rear of
the readout box to a computer.
Water Chamber – Special care should be taken to
see that the four (4) roller bearings between the water
chamber and the base slide tracks are properly cleaned
and contain a slight amount of oil during and after use.
We advise using a cover over the direct shear after
use to eliminate dust from entering the precision slide
assembly. The main drive shaft should be at its home
position. This will place the sample load pad in the cen-
ter of the crossarm for consolidation.
Shear Boxes (sold separately) – The shear rings are
held together with (2) stainless steel screws boxes.
There are also (4) screws for adjusting the gap be-
tween the rings once consolidation has been reached.
The gap is adjusted by turning the screws clockwise
from the nger tight position. One full turn will give
.031” gap. There is a line scribed on the adjusting knob
for determining how much gap each screw has provid-
ed. The screws should be turned evenly to maintain
a proper gap. At the bottom of each screw is a nylon
glide which keeps the top shear ring from dropping
during the test.
FRONT PANEL CONTROLS
The consolidation load settings and strain rates
are controlled from the front panel. Machine
must be plugged in to a properly wired ground-
ed receptable with appropriate electrical current.
PANEL CONTROLS — LOAD SETTING
Readout and Data Acquisition – See manual for
Data Readout System. This is a four channel device for
monitoring shear load (channel 1), horizontal displace-
ment (channel 2), vertical displacement (channel 3),
and pressure (channel 4) for setting the vertical load
on the sample. See the load table for the proper load
setting.
Load Regulator – A precision Fairchild regulator is
used to set and maintain the air pressure to the pis-
tons which provides load to the sample. The regulator
is sensitive to 1/8” variations in water column. Select
the load required from the load setting table.
Note: The consolidation load pad, porous stone, and
stainless-steel ball have not been included in the load
setting calibrations.
High Load/Low Load Selector Valve – This valve
hastwopositions.TheLOWLOADpositionisusedfor
loads up to 100lbs. The HIGH LOAD position is used
for loads up to 1500lbs.
Load Valve – This valve is actuated by 90-degree ro-
tation of the handle. When open it allows air to ow
fromtheregulatortothepistons(HIGHorLOWLOAD)
selected.
PANEL CONTROLS — POWER & SHEAR RATE
Power Switch – An indicator light is present when
power is turned on.
Strain Rate Selector – The strain rate is set with
thumbwheel selectors. The switches are direct read-
ing in inches/minute (or mm/min for HM-382F) with an
implied leading decimal point. Once the rate is set and

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the test is started, the switch setting is ignored until the
stop switch is pressed or a limit switch is tripped.
Limit Switches – These switches are located on the
platform behind the water chamber.
Adjustment of the limit switches is made by loosening
the Phillips-head screws and moving the limit switch
assembly in the direction desired. The home position
has been set so that the load crossarm is in the middle
of the shear rings.
Note: The limit of travel of the drive shaft is dependent
on the limit switch settings. Do not operate the drive
motor with the water chamber disconnected because
this will make the limit switches inoperable.
Stop Switch – Push button to stop the
motor.
Direction Switch – Momentary (spring loaded) switch.
After setting the desired shear rate, moving the switch
in the desired direction will initiate movement. This
switch will then become inactive until the stop button is
pressed, or a limit switch is activated. The left position
will move the water chamber to the left. It will continue
until the water chamber activates the limit switch. At
this time, the limit indicator light will be lit. The right
switch position will move the shear box to the right until
the home limit switch is made. See above note…
Residual Counter – Two-digit thumbwheel is used for
setting the number of residual shear passes required.
One shear pass will allow the shear box to travel from
the home position to the limit switch setting. Two pass-
es will travel from the home position out to the limit
switch and then return to the home position. Each
pass completed will register on the digital readout to
the right of the thumbwheels. Choose between 0-99
passes.
Home & Limit Indicators – Used to indicate the limit
of travel of the shear box.
Fuse – 4 amp SLO BLO fuse located in the cabinet
rear.
OPERATING INSTRUCTIONS
Read all operating instructions before performing a test
and refer to ASTM D3080 or AASHTO T 236 for com-
plete test procedures and calculations.
Set Up
1. Place the shear box into the water chamber and se-
cure the load cell shaft to the top of the shear box.
2. Tighten the two shear ring clamping knobs located
on the left side of the water chamber.
3. Install the counterbalance, Model 2000-75, if nec-
essary.
4. Tare the load cell by pressing the “Tare” button on
the digital readout.
5. Adjust the top cross arm and dial gauge so there is
1/8in gap between the cross arm and loading ball.
Align the cross arm pin so it is above the loading
ball. Make sure the cross arm is level.
6. Adjust the LVDT by raising or lowering the indicator
rod and holder so the tip of the LVDT is resting on
the cross arm pin.
Consolidation
1. Select a seating load with the load setting calibration
chart.SettheHIGHLOADorLOWLOADknobto
LOWandtheLoadValveto“LOAD.”
2. Adjust the Fairchild Pressure Regulator to the de-
sired seating load per the load setting calibration
chart, this value is displayed on the digital readout
box, channel 4.
3. Turn the “LOAD” knob to “OFF” and adjust the Pres-
sure Regulator to the desired normal load based
on the load calibration chart. If reading from the
“LOW”calibrationchartkeeptheknobontheLOW
LOAD position. If reading from the “HIGH” calibra-
tion chart, turn the knob to “HIGH LOAD”
4. Tare the LVDT on channel 3 before beginning con-
solidation.
5. Turn the Load Valve to “LOAD” to begin consolida-
tion.
6. Load and swell readings will be displayed on chan-
nels 3 and 4 of the readout box and transferred to
an Excel le or the Direct Shear DataAcquisition
Software on the users connected computer.
Direct Shear
1. After consolidation phase is complete, add a small
seating shear load by adjusting the two knurled nuts
on the load cell support.
2. Tare the shear load cell which is displayed on chan-
nel 1 of the digital readout box.
3. Remove the two holding screws on the shear box
to separate the top and bottom sections. Adjust the
four adjusting screws on the shear box to set the
gap between the top and bottom of the shear box.
One full turn of these adjusting screws will give a
0.031in (0.78mm) gap.

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4. Set the shear/strain rate with the thumbwheels on
the left side of the machine. Each number is set by
pushing the thumbwheel button, the rate is in inches
per minute (0001 = 0.0001 in/min).
5. Tare the horizontal displacement LVDT on channel
2 of the readout box. To begin shear, switch the DI-
RECTION toggle switch to the left towards the LIMIT
light.
6. The water chamber with shear box will continue to
move at the set rate until the limit switch is activated
or the STOP button is pressed.
7. Load and Shear Displacement will be displayed
on channels 1 and 2 of the digital readout box and
transferredtoanExcelleortheDirectShearData
Acquisition Software on the users connected com-
puter.
8. At the test completion, switch the DIRECTION tog-
gle to the right towards the HOME light. Press the
stop button when Zero load is reached on the load
cell, channel 1 of the readout box.
8A. If Residual Shear values are needed, these can be
determined during this time.
9. Reduce the vertical load to Zero by adjusting the
Fairchild Pressure Regulator until Zero psi is
reached on the digital readout box.
10. The Shear Box can now be removed from the wa-
ter chamber and the sample can be inspected.
MAINTENANCE
Special care should be taken to see that the four roll-
er bearings between the water chamber and the base
slide track are properly cleaned and contain a slight
amount of oil during and after use. It is recommended
to cover the Direct Shear machine when not in use to
prevent dust buildup.
Empty the water chamber after each test to prevent
soil and sand buildup inside the chamber. The water
can be drained from the port or the chamber can be
removed from the Direct Shear Machine for thorough
cleaning.
ACCESSORIES
HMA-95 Pneumatic Shear Machine Rolling Cart
HMA-739 Shear Box Counterbalance
HMA-610 Direct/Residual Shear Data Acquisition
Software