NPK C2D User manual

Compactors
Compactors
!Oil Splash Lubrication
!Integrated Flow Control and
Pressure Relieving Valves
!Optional Backfill Blades
!Industry’s Most Comprehensive
Field Service Corps
!Extensive Parts Distribution
System
!Network of Over 350
Distributor Outlets
NPK ATTACHMENTS...designed, built and backed by NPK.
NPK ATTACHMENTS...designed, built and backed by NPK.

Greater impulse energy for more
compactor/driver productivity!
Greater impulse energy for more
compactor/driver productivity!
NPK Compactor/Drivers are designed and built to meet today’s demands for greater jobsite productivity, expanding
and enhancing the versatility of your backhoe or excavator.
The leader in trench compaction technology, NPK delivers the industry’s
greatest impulse forces with overall superior performance through
hydraulically operated rotating eccentric action. Greater vibration
forces generate stress waves in granular or loose soil material,
bringing the soil’s air to the surface and packing the particles
closer together. Greater impulse action works together with
the carrier’s downward forces to compact cohesive
clay-type soils.
Do more work safely a boom’s length away
NPK’s versatile Compactor/Driver can work productively virtually anywhere your excavator or backhoe boom can
reach. In trenches, over and around pipe, to the top of piling and sheeting. Next to foundations and around
obstructions. Even on steep slopes or rough terrain where conventional rollers and other machines either can’t work
or would be hazardous to try. In fact, NPK’s Compactor/Drivers can keep workers a full boom’s length from the
compaction or driving action, away from the danger of cave-ins or equipment contact.
Select the NPK Compactor/Driver
that’s right for your application
NPK’s full selection of Compactor/Drivers
gives you the exact power you need
for your jobs and jobsite conditions.
The right model for carriers
ranging from the smallest
mini-excavators and
backhoe/loaders
to the larger excavators.
Headlining the list of models
is NPK’s C-12C, largest
and most powerful
boom mounted plate
Compactor/Driver
available anywhere.
NPK’s Compactor/Drivers
deliver the industry’s
greatest impulse forces
with hydraulically
operated rotating
eccentric action.
Durable rubber shock
mounts, solid welds and self aligning,
double row, spherical roller bearings
guarantee overall superior performance.
Optional swivel top to minimize carrier repositioning
(not available on the Model C-2D), or optional dedicated
top brackets available for quick-attach applications.
Heavy-duty, high-efficiency gear motor.
Self-aligning, double row
spherical roller bearings.
Oil splash lubrication,
eliminates routine greasing.
Rubber shock
mounts to
isolate vibration.
Direct drive
eccentric
mass.

Cost saving versatility
that is more than a promise!
NPK Compactor/Drivers actually deliver on the promise of greater cost-efficiency and jobsite versatility -
operating advantages that are absolutely required by today’s contractors and budget-conscious
municipalities. Utilizing your carrier’s hydraulic system, you save on fuel as well as the need for other costly ma-
chines and equipment, using your versatile NPK Compactor/Driver for:
!Compacting or driving anywhere a boom can go, and often where a man cannot.
!Driving wood and aluminum sheeting, fence posts, guardrail posts,
rail and I-beams, piling and seawalls, etc.
!Soil and aggregate compaction.
!Trench compaction, as deep as a bucket can dig.
!Steep slope compaction.
!Waste compaction at transfer stations, etc.
!Breaking up frozen coal, salt and other material.
!Extracting piling and sheeting.
Swivel feature to avoid machine repositioning
NPK’s optional self-aligning swivel can align your Compactor/Driver to nearly any job from nearly any carrier
position. With an excavator positioned over, parallel or perpendicular to the job, you can work productively in tight
quarters, narrow trenches next to foundation walls and around manholes or other obstacles. When it’s not needed,
the swivel can be locked in place, either parallel or perpendicular to the boom.
Designed and built for reliability
NPK Compactor/Drivers are designed
and built for optimum dependability
on the most demanding jobsites.
Rugged welds, heavy-duty direct drive
gear motors, durable rubber shock
mounts and self aligning, double row,
spherical roller bearings with a
heavy-duty roller cage.
Cost saving versatility
that is more than a promise!
Integrated flow control
and pressure relieving valves
protect the motor from
excessive flow
and pressure.
Hoses are routed out of the
back of the compactor,
safely away from the
trench wall.
Internally
routed hoses
for maximum
protection.
Optional backfill blade-
available on all models.
Dual backfill blades also
available improving your
ability to push or pull soil,
gravel and debris without
having to rotate the compactor
or reposition the excavator.
These backfill blades are
bolt-on and can be
easily removed
for trenchwork and
transport (note:
when the backfill
blade(s) are
removed the
backfill blade
bracket
does not
extend past
the baseplate).

COMPACTORS
COMPACTORS
More compacting power with excavators and backhoes
NPK Construction Equipment, Inc.
7550 Independence Drive
Walton Hills, OH 44146-5541
Phone [phone]
Toll-free [phone]
Fax [phone]
Internet: www.npkce.com
Each product sold by NPK is subject to an express written warranty. NPK makes no other warranty, express or implied, including any warranty of merchantability or fitness for any
particular purpose. NPK is not liable for any incidental or consequential damages.
Printed in U.S.A. Form No. B06-0100 (05/19) © Copyright 2019, NPK Construction Equipment, Inc.
Sold and Serviced by:
NPK...All the Right Attachments! With innovation throughout construction’s most extensive line.
Hydraulic Hammers Concrete Crushers Material Processors Demolition Shears Demolition Grabs Sheet Pile Drivers Pedestal Breaker Systems
* Operating pressures shown are with standard hydraulic motor. Operating pressures will be different with optional hydraulic motors.
Options are available for special applications. Weight does not include mounting bracket. Specifications subject to change without notice.
Specifications
NPK Model
C-2D C-3D C-4C C-6C C-8C C-10C C-12C
Impulse Force 3,500 lbf 6,000 lbf 7,800 lbf 16,000 lbf 24,000 lbf 34,000 lbf 45,000 lbf
Cycles per Minute 2400 2200 2100 2200 2200 2200 2200
Oil Flow Required (Standard) 13 gpm 16 gpm 22 gpm 33 gpm 43 gpm 51 gpm 70 gpm
(Low Flow Option) Please Contact NPK
Operating Pressure* 1500-2000 psi 1950-2450 psi 1700-2200 psi 1800-2300 psi 2000-2500 psi 2000-2500 psi 2000-2500 psi
Relief Pressure Setting 2500 psi 2600 psi 2600 psi 2600 psi 2600 psi 2600 psi 2600 psi
Swivel Feature N/A Optional Optional Optional Optional Optional Optional
Baseplate Dimensions 12 x 25 in 17 x 28 in 23 x 34 in 29 x 40 in 34 x 46 in 40 x 52 in 45 x 58 in
Compaction Area 2.1 sq ft 3.3 sq ft 5.4 sq ft 8.1 sq ft 10.9 sq ft 14.5 sq ft 18.1 sq ft
Narrow Baseplate N/A N/A Special Order Special Order Special Order Special Order Special Order
Weight (Fixed) 390 lb 700 lb 800 lb 1535 lb 2100 lb 3400 lb 4000 lb
(Swivel) N/A 800 lb 960 lb 1715 lb 2325 lb 3615 lb 4475 lb
Height (Fixed) 28 in 29 in 30 in 39 in 45 in 50 in 55 in
Width 12 in 17 in 23 in 29 in 34 in 40 in 45 in
Recommended 2.5-6 tons 3.5-9 tons 5-12.5 tons 8-21 tons 15-32.5 tons 30-50 tons 40-70 tons
Carrier Weight

HYDRAULIC
COMPACTOR/DRIVER
OPERATORS MANUAL
MODELS:
C2D, C2C, C2
C3D
C4C, C4B, C4A, C4
C6C, C6B, C6
C8C, C8B, C8
C10C, C10
C12C, C12
“Use Genuine NPK Parts”
© Copyright 2020 NPK Construction Equipment, Inc. www.npkce.com C000-9610C Compactor
Operators Manual 9-20
7550 Independence Drive
Walton Hills, OH 44146-5541
Phone [phone]
Fax [phone]

CONTENTS
- 1 -
SAFETY........................................................................................................................................2
FORWARD ...................................................................................................................................4
COMPACTOR/DRIVER APPLICATIONS.....................................................................................4
MAINTENANCE............................................................................................................................5
STANDARD PRACTICES.................................................................................................5
CARRIER COMPATIBILITY .........................................................................................................6
SPECIFICATIONS........................................................................................................................7
COMPACTOR/DRIVER STRUCTURE.......................................................................................10
C2D THROUGH C12C COMPACTOR/DRIVERS...........................................................10
COMPACTOR/DRIVER SERIAL NUMBER LOCATION ............................................................14
UNDERSTANDING COMPACTION ...........................................................................................15
COMPACTION FORCES............................................................................................................16
SOIL MATERIAL.........................................................................................................................17
SOIL DENSITY TESTING...........................................................................................................19
LABORATORY TESTS ...................................................................................................19
FIELD TESTS..................................................................................................................21
FIELD TEST REPORT....................................................................................................23
CLASSIFICATION OF COMPACTION EQUIPMENT.................................................................24
COMPACTION METHODS AND EQUIPMENT SELECTION ....................................................25
COMPACTOR MODEL SIZE vs PERFORMANCE ....................................................................25
PRODUCTIVITY .........................................................................................................................26
HYDRAULIC INSTALLATION.....................................................................................................27
BACKHOE/EXCAVATOR COMPACTOR LINES............................................................27
SHUT-OFF VALVES .......................................................................................................27
COMPACTOR CONTROL VALVE..................................................................................28
RETURN OIL...................................................................................................................28
PREVENTION OF CONTAMINATION............................................................................29
CHANGING THE FILTER ELEMENT AND HYDRAULIC OIL .........................................29
HYDRAULIC QUICK DISCONNECTS ............................................................................30
BACKFILL ATTACHMENT .........................................................................................................33
BEFORE OPERATION...............................................................................................................34
DECIDE IF SWIVEL LOCK FEATURE WILL BE USED ..................................................34
BEFORE OPERATION...............................................................................................................35
LUBRICATION................................................................................................................35
MAINTENANCE AND INSPECTION..........................................................................................36
DAILY MAINTENANCE...................................................................................................36
LUBRICANT TERMS AND DEFINITIONS..................................................................................37
OPERATION...............................................................................................................................39
SOIL COMPACTION.......................................................................................................40
LEAVE IT RUNNING.......................................................................................................41
COMPACTION AROUND PIPE ......................................................................................41
NARROW TRENCH COMPACTION...............................................................................42
SHEET/PILE DRIVING AND EXTRACTING ...................................................................43
SHEET/PILE AND POST/PIPE ADAPTERS...................................................................43
SWIVEL FEATURE.........................................................................................................44
STORAGE OF THE COMPACTOR/DRIVER .............................................................................45
WARRANTY REGISTRATION FOR NEW UNITS......................................................................46
WARRANTY STATEMENTS ......................................................................................................47
NOTES AND RECORDS............................................................................................................49

NPK
- 2 -
SAFETY
Safety notices in NPK Instruction Manuals follow ISO and ANSI standards for
safety warnings:
DANGER (red) notices indicate an imminently hazardous situation
which, if not avoided, will result in death or serious injury.
WARNING (orange) notices indicate a potentially hazardous situation
which, if not avoided, could result in death or serious injury.
CAUTION (yellow) notices indicate a potentially hazardous situation,
which, if not avoided, may result in minor or moderate injury.
ATTENTION (blue) notices in NPK Instruction Manuals are an NPK
standard to alert the reader to situations which, if not avoided, could
result in equipment damage.
1. Operators and service personnel must read, understand and comply with the NPK
INSTRUCTION MANUAL.
2. Keep personnel and bystanders clear of the COMPACTOR/DRIVER while in
operation.
3. Do not operate the COMPACTOR/DRIVER without an impact resistant shield
between the COMPACTOR/DRIVER and the operator.
4. The COMPACTOR/DRIVER must not be operated unless the operator is in full
control of the carrier. Operate the COMPACTOR/DRIVER from the operator’s seat
only.
5. Match the COMPACTOR/DRIVER size to carrier according to NPK
recommendations. See the CARRIER MACHINE COMPATIBILITY section of this
manual.
6. Service personnel must be cautious handling pins and bushings when exchanging
the bucket for the COMPACTOR/DRIVER. The carrier machine operator must
move the stick or boom only when directed by service personnel.
7. If it is necessary to hammer the boom pins in or out, beware of flying metal chips.
Eye protection be worn!
8. Do not operate the COMPACTOR/DRIVER if the hydraulic oil temperature exceeds
180° F (80° C), or at higher than specified flow rates.
9. Be especially cautious around hydraulic lines. Hydraulic oil can be extremely HOT!
Avoid skin contact with hydraulic oil! It can cause severe burns!
10. Protect hands and body from hydraulic fluids under pressure. Escaping high
pressure fluid can penetrate the skin, causing serious injury. Avoid the hazard by
relieving the pressure form the hydraulic system before disconnecting any lines.
Search for leaks with a piece of cardboard or other object. If an accident occurs,
seek medical attention immediately! Hydraulic fluid injected into the skin
must be surgically removed immediately or gangrene may result!

NPK
- 3 -
SAFETY
11. Make daily visual inspections of all fasteners, boom pins, hoses, etc.
12. Do not make any alterations to the COMPACTOR/DRIVER without authorization
from NPK Engineering.
13. Use only NPK supplied replacement parts. NPK specifically disclaims any
responsibility for bodily injury or COMPACTOR/DRIVER damage that results from
the use of parts not sold or approved by NPK.
14. Be careful when you torque fasteners. An overstressed or damaged component
may fail.
15. Use the proper lifting equipment and tools when handling or servicing the
COMPACTOR/DRIVER or components.
16. Important safety and operating decals are included with each
COMPACTOR/DRIVER and HYDRAULIC INSTALLATION KIT. Keep them clean
and visible. NPK will replace decals free of charge as needed.

NPK
- 4 -
FORWARD
This manual has been written to give the necessary instructions for operating,
maintaining, and servicing the NPK Compactor/Driver. Read this manual before start-
up.
For help with any problems encountered, or additional information, contact your NPK
authorized Distributor.
Use replacement parts sold by NPK only. NPK is not responsible for failures resulting
from alterations not approved by NPK or substitution of parts not sold by NPK. Do not
operate the Compactor/Driver underwater without instructions from NPK Engineering.
COMPACTOR/DRIVER APPLICATIONS
The excavator mounted Compactor/Driver is a mobile, self-contained unit that operates
anywhere a boom can reach. This versatile attachment compacts in the trench, around
and over pipe, or reaches to the top of piling and sheeting for driving or extracting in the
toughest of conditions and in rough terrain areas. The mounted Compactor keeps the
workers out of the trench and safe from cave-ins. Even slopes that are too steep for a
conventional roller can be easily reached for compaction.
APPLICATIONS INCLUDE:
•HIGH PRODUCTION SOIL AND AGGREGATE COMPACTION.
•DEEP TRENCH COMPACTION, AS DEEP AS A BUCKET CAN DIG.
•SLOPE COMPACTION.
•WASTE COMPACTION AT TRANSFER STATIONS, ETC.
•BREAKING UP FROZEN MATERIAL, SUCH AS COAL, SALT, ETC.
•DRIVING PILE, SHEET, FENCE POSTS, GUARDRAIL POSTS, ETC.
•EXTRACTION OF PILING AND SHEETING.
•COMPACTING OR DRIVING ANYWHERE A BOOM CAN GO . . . AND MAN
CANNOT.

NPK
- 5 -
MAINTENANCE
STANDARD PRACTICES
Maintenance of and repairs to the COMPACTOR/DRIVER should be performed by an
experienced service technician, thoroughly familiar with all standard practices and
procedures, and most importantly, all safety precautions. The following is a review of
common standard practices to be followed when working with hydraulic equipment, and
is not meant to be all-inclusive. Rather, this review is presented as a reminder as to
some of the unique characteristics of hydraulic equipment.
•The prevention of foreign contaminant damage is critical when working with hydraulic
equipment. Protect exposed holes and parts to guard against entry of contaminants.
Install metal or plastic plugs/caps where applicable to prevent entry of debris into the
hydraulic system.
•Mark the location and position of mating parts as an aid to re-assembly. Mark
corresponding parts uniquely to reflect their relationship, including proper location,
position, orientation, and/or alignment.
DO:
•During assembly, observe all markings made during disassembly, and all
corresponding features of mating parts to ensure proper location, position, orientation
and alignment.
•During disassembly of a sub-assembly, place removed components on a clean, dry
surface, in proper relative position as an aid in re-assembly.
•Always inspect threaded areas on components. Repair or replace as required.
Never apply uncured thread adhesive to a fastener that has cured adhesive on it.
Clean the fastener and the threaded bore. A tap and die may be helpful for this task.
Be sure to remove loose debris from the threaded bore.
•Use care to avoid scratches, nicks, dents, or other damage to machined surfaces of
mating components.
•When securing a component, always tighten cap screws gradually in an opposing
pattern, applying the specific torque.
•Grease can be used to temporarily hold a part in place while the abutting part is
placed into position.
•Always use common sense and exercise standard safety precautions when working
with all tools and equipment required to maintain, repair or troubleshoot the
COMPACTOR/DRIVER.

NPK
- 6 -
CARRIER COMPATIBILITY
These carrier weight ranges are intended as a guideline only. Other factors, such as
stick length, counterweights, undercarriage, etc., must be taken into consideration.
Mounting a Compactor that is too heavy for the carrier machine is inefficient. The result
is an inadequate amount of downforce which can be dangerous and can damage the
carrier. Verify the carrier stability with the Compactor before transport or operation.
Mounting a Compactor that is too small for the carrier machine can damage the unit and
void the Warranty.
Consult NPK, if there is uncertainty whether the compactor model is compatible.
COMPACTOR/DRIVER
RECOMMENDED CARRIER WEIGHT
MODEL
lb.
(kg)
C2D, C2C, C2
5,000 - 12,000
(2,300 - 5,500)
C3D
7,000 - 18,000
(3,220 - 8,250)
C4C, C4B, C4A, C4
10,000 - 25,000
(4,500 - 11,500)
C6C, C6B, C6
16,000 - 42,000
(7,000 - 19,000)
C8C, C8
30,000 - 65,000
(14,000 - 29,500)
C8B
30,000 - 75,000
(14,000 - 34,400)
C10
35,000 - 60,000
(15,875 - 27,250)
C10C, C12
60,000 - 100,000
(27,000 - 45,000)
C12C
80,000 - 140,000
(36,000 - 63,500)
(Specifications subject to change without notice.)

NPK
- 7 -
SPECIFICATIONS
MODEL
CYCLES
OIL FLOW
OIL FLOW
OIL FLOW
PER
(standard)
(low flow option)
(high flow option)
MINUTE
gpm
(lpm)
gpm
(lpm)
gpm
(lpm)
C2D
2,400
13
(49)
CONTACT NPK
N/A
C2C
2,200
13
(49)
10
(38)
N/A
C2
2,200
15
(56)
10
(38)
N/A
C3D
2,200
16
(61)
N/A
N/A
C4C
2,100
22
(83)
CONTACT NPK
N/A
C4B
2,200
22
(83)
16
(61)
30
(114)
C4A/C4
2,200
22
(83)
15
(56)
N/A
C6C
2,200
33
(125)
25.5
(97)
N/A
C6B
2,200
33
(125)
28
(106)
40
(151)
C6
2,200
33
(125)
N/A
40
(151)
C8C
2,200
43
(160)
CONTACT NPK
N/A
C8B
2,200
43
(160)
33
(125)
55
(210)
C8
2,200
40
(151)
N/A
55
(210)
C10C
2,200
51
(210)
CONTACT NPK
N/A
C10**
N/A
N/A
N/A
N/A
N/A
C12C
2,200
70
(265)
CONTACT NPK
N/A
C12
2,400
55
(210)
40
(151)
62
(235)
**Contact NPK for assistance at [phone]
MODEL
IMPULSE
OPERATING
RELIEF VALVE
FORCE
PRESSURE₁
PRESSURE SETTING₂
lbf
(kgf)
psi
(bar)
psi
(bar)
C2D*
3,500
(1,590)
1500-2000
(105-140)
2500
(170)
C2C*
3,500
(1,590)
1500-2000
(105-140)
2500
(170)
C2
3,500
(1,590)
1500-2000
(105-140)
2500
(170)
C3D*
6,000
(2,720)
1700-2200
(117-150)
2500
(170)
C4C*
7,800
(3,550)
1700-2200
(117-150)
2600
(180)
C4B
7,800
(3,550)
1700-2200
(117-150)
2600
(180)
C4A, C4
7,800
(3,550)
1700-2200
(117-150)
2600
(180)
C6C*
16,000
(7,300)
1800-2300
(125-160)
2600
(180)
C6B
16,000
(7,300)
1800-2300
(125-160)
2600
(180)
C6
16,000
(7,300)
1800-2300
(125-160)
2600
(180)
C8C*
24,000
(11,000)
2000-2500
(140-170)
2600
(180)
C8B
24,000
(11,000)
2000-2500
(140-170)
2600
(180)
C8
24,000
(11,000)
2000-2500
(140-170)
2600
(180)
C10C*
34,000
(15,450)
2000-2500
(140-170)
2600
(180)
C10**
N/A
N/A
N/A
N/A
N/A
N/A
C12C*
45,000
(20,420)
2000-2500
(140-170)
2600
(180)
C12
38,000
(17,300)
2400-2800
(165-195)
3000
(207)
*Denotes NPK "C" and "D" model compactor/drivers that have built in relief valves.
The carrier circuit relief valve settings should be a minimum of 200 psi (14 bar) above the
compactor/driver relief settings.
"A" and "B" model NPK compactor/drivers rely on the carrier's circuit relief valve.
**Call NPK for assistance at [phone].
1. Operating pressures shown are with a standard hydraulic motor. Operating pressures will be
different with optional hydraulic motors.
2. Relief pressure setting shown is for a standard hydraulic motor. For a relief with different
motor options, contact NPK at [phone].
(Specifications subject to change without notice.)

NPK
- 8 -
SPECIFICATIONS
MODEL
WEIGHT (WITHOUT TOP BRACKET)
FIXED TOP
SWIVEL TOP
FIXED TOP
SWIVEL TOP
STANDARD BASE
STANDARD BASE
NARROW BASE
NARROW BASE
lb.
(kg)
lb.
(kg)
lb.
(kg)
lb.
(kg)
C2D
390
(177)
N/A
N/A
N/A
C2C
380
(170)
N/A
N/A
N/A
C2
380
(170)
N/A
N/A
N/A
C3D
700
(318)
800
(363)
N/A
N/A
C4C
800
(363)
960
(436)
870
(395)
920
(418)
C4B
850
(385)
875
(400)
N/A
N/A
C4A/C4
850
(385)
875
(400)
N/A
N/A
C6C
1535
(696)
1715
(778)
N/A
N/A
C6B
1450
(660)
1500
(680)
N/A
N/A
C6
1500
(680)
N/A
N/A
N/A
C8C
2100
(953)
2325
(1056)
N/A
N/A
C8B
1950
(890)
2000
(910)
N/A
N/A
C8
2000
(910)
N/A
N/A
N/A
C10C
3400
(1542)
3515
(1640)
N/A
N/A
C10**
N/A
N/A
N/A
N/A
C12C
4000
(1814)
4475
(2030)
N/A
N/A
C12
4040
(1835)
4120
(1870)
N/A
N/A
**Contact NPK for assistance at [phone].
MODEL
HEIGHTH
WIDTH
INSIDE BRACKET
WIDTH₃
in.
(mm)
in.
(mm)
in.
(mm)
C2D
28
(711)
12
(305)
7
(178)
C2C
28
(711)
14
(356)
7
(178)
C2
25
(635)
14
(356)
7
(178)
C3D
29
(737)
17
(432)
10-1/4
(260)
C4C
30
(762)
23
(584)
10-1/4
(260)
C4B
30
(762)
24
(610)
10-1/4
(260)
C4A/C4
30
(762)
24
(610)
10-1/4
(260)
C6C
39
(991)
29
(736)
12-1/2
(318)
C6B
39
(991)
29
(736)
12-1/2
(318)
C6
39
(991)
29
(736)
12-1/2
(318)
C8C
45
(1143)
34
(864)
14-9/16
(370)
C8B
45
(1143)
34
(864)
14-9/16
(370)
C8
45
(1143)
34
(864)
14-9/16
(370)
C10C
50
(1270)
40
(1016)
Varies with carrier
C10**
N/A
N/A
34
(864)
N/A
N/A
C12C
55
(1397)
45
(1143)
Varies with carrier
C12
47
(1195)
45
(1143)
14-9/16
(370)
**Contact NPK for assistance at [phone].
3. Options are available for special applications.
(Specifications subject to change without notice.)

NPK
- 9 -
SPECIFICATIONS
MODEL
SWIVEL
STANDARD BASEPLATE
NARROW BASEPLATE
FEATURE
Dimensions
Compaction
Dimensions
Compaction
Area
Area
in.
(cm)
sq.
ft.
(sq m)
in.
(cm)
sq.
ft.
(sq m)
C2D
N/A
12 x 25
(32 x 63.5)
2.1
(0.2)
N/A
N/A
C2C
N/A
14 x 22
(36 x 56)
2.1
(0.2)
N/A
N/A
C2
N/A
14 x 22
(36 x 56)
2.1
(0.2)
N/A
N/A
C3D
OPTIONAL
17 x 28
(43 x 69)
3.3
(0.3)
N/A
N/A
C4C
OPTIONAL
23 x 34
(58 x 86)
5.4
(0.5)
18 x 34
(46 x 86)
4.3
(0.4)
C4B
OPTIONAL
24 x 34
(61 x 86)
5.7
(0.5)
N/A
N/A
C4A/C4
OPTIONAL
24 x 34
(61 x 86)
5.7
(0.5)
N/A
N/A
C6C
OPTIONAL
29 x 40
(74 x 102)
8.1
(0.75)
SP. ORDER
C6B
OPTIONAL
29 x 40
(74 x 102)
8.1
(0.75)
N/A
N/A
C6
STANDARD
29 x 40
(74 x 102)
8.1
(0.75)
N/A
N/A
C8C
OPTIONAL
34 x 46
(86 x 117)
10.9
(1.0)
SP. ORDER
C8B
OPTIONAL
34 x 46
(86 x 117)
10.9
(1.0)
N/A
N/A
C8
STANDARD
34 x 46
(86 x 117)
10.9
(1.0)
N/A
N/A
C10C
OPTIONAL
40 x 52
(102 x 132)
14.5
(1.3)
SP. ORDER
C10**
OPTIONAL
34 x 46
(86 x 117)
10.9
(1.0)
N/A
N/A
C12C
OPTIONAL
45 x 58
(114 x 147)
18.1
(1.7)
SP. ORDER
C12
OPTIONAL
40 x 55
(101 x 140)
15.2
(1.36)
N/A
N/A
(Specifications subject to change without notice.)

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COMPACTOR/DRIVER STRUCTURE
C2D THROUGH C12C COMPACTOR/DRIVERS
The C2D through C12C Compactor/Drivers consist of a top bracket, an upper frame and
a lower frame. The C2D Compactor has a fixed top bracket only. The C3D, C4C, C6C,
C8C, C10C, and C12C Compactor/Drivers are available with fixed or swivel top
brackets.
The C2D, C3D, C4C, C6C, and C8C upper frames are mounted to the lower frames
with four bolt-on rubber mounts. C10C and C12C models use eight bolt-on rubber
mounts. The rubber mounts reduce the amount of vibration being transmitted to the
carrier.
The lower frame contains an eccentric weight suspended on roller bearings and spun by
a hydraulic motor. The baseplate of these units is a welded part of the lower frame.
The upper frame contains a bolt-on hydraulic manifold (B, C, and D Series only).
ITEM
DESCRIPTION
bp1
BOTTOM PLATE
BQ
HYDRAULIC MOTOR
DY
RUBBER MOUNT
EG
UPPER FRAME
EH
LOWER FRAME
m7
TOP BRACKET
MODEL C2D

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COMPACTOR/DRIVER STRUCTURE
C2D THROUGH C12C COMPACTOR/DRIVERS
MODEL C3D
ITEM
DESCRIPTION
bp1
BOTTOM PLATE
BQ
HYDRAULIC MOTOR
C3D
BQ1
HYDRAULIC MOTOR
C4C
DY
RUBBER MOUNT
EG
UPPER FRAME
EH
LOWER FRAME
EI
THRUST COVER
EJ
UPPER THRUST PLATE
EJ1
LOWER THRUST
PLATE
EK
THRUST BEARING
FK
SWIVEL HUB (bolt-on)
m7
TOP BRACKET
MODEL C4C
FIXED
SWIVEL

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COMPACTOR/DRIVER STRUCTURE
C2D THROUGH C12C COMPACTOR/DRIVERS
MODEL C6C
ITEM
DESCRIPTION
bp1
BOTTOM PLATE
BQ
HYDRAULIC MOTOR
(C6)
BQ1
HYDRAULIC MOTOR
(C8)
DY
RUBBER MOUNT
EG
UPPER FRAME
EH
LOWER FRAME
EI
THRUST COVER
EJ
UPPER THRUST
PLATE
EJ1
LOWER THRUST
PLATE
EK
THRUST BEARING
FK
SWIVEL HUB (weld-on)
m7
TOP BRACKET
MODEL C8C
FIXED
SWIVEL

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COMPACTOR/DRIVER STRUCTURE
C2D THROUGH C12C COMPACTOR/DRIVERS
MODEL C10C
ITEM
DESCRIPTION
bp1
BOTTOM PLATE
BQ
HYDRAULIC MOTOR
DY
RUBBER MOUNT
EG
UPPER FRAME
EH
LOWER FRAME
EI
THRUST COVER
EJ
UPPER THRUST
PLATE
EJ1
LOWER THRUST
PLATE
EK
THRUST BEARING
FK
SWIVEL HUB (weld-on)
m7
TOP BRACKET
MODEL C12C
FIXED
SWIVEL

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COMPACTOR/DRIVER SERIAL NUMBER
LOCATION
The serial number of your unit is required any time that you are placing a parts order or
requiring technical assistance. Failure to use the serial number when ordering parts,
may result in receiving the incorrect parts, resulting in additional cost and down time.
The serial number will be comprised of the following sequence of numbers and letters:
0N-0000. (Units that shipped before July of 1999, will have a five-digit number stamped
into the upper frame.)
The location described below is between the inlet and outlet hydraulic ports on the
upper frame.
The serial number tag (sn2) can be found on the upper frame assembly. Additionally,
the serial number (sn1) is stamped below the serial number tag on the upper frame
assembly.

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The extent to which a soil can be compacted
depends on three major factors:
1. The type of soil and its compactability.
2. The moisture content of the soil.
3. The type of compaction effort required, that
is pressing, ramming, or vibration.
UNDERSTANDING COMPACTION
Whenever the earth is disturbed, it loses its
original density. In order to regain that density,
it must be manipulated by some mechanical
means.
Compaction is the reduction in soil volume that
occurs when force is applied to it. The
application of external compressive forces
increases the soil density or unit weight by
mechanically rearranging and moving soil
particles closer to each other, and forcing out
the air that has been trapped between these
particles. Increasing the density of the soil
improves the ability of the soil to support a load
and reduces the possibility of settling. This is
particularly important when loose fill is placed in
a trench or any other open area. Non-
compacted fill will slowly settle, causing a void
and allowing the surface to fall into the void.