NPK U Series User manual

U and G-SERIES SECONDARY
CONCRETE CRUSHERS
MODELS U21J, U21JR, U31J, U31JR
U45J, U45JR, G7, G18J, G26J, G30JR
OPERATION AND MAINTENANCE MANUAL
© Copyright 2018 NPK Construction Equipment, Inc. www.npkce.com U000-9600B U and
G Series Crushers Operation Manual 10-18
7550 Independence Drive
Walton Hills, OH 44146-5541
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Toll-free [phone]
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"Use Genuine NPK Parts”
"Use Genuine NPK Parts”

1
CONTENTS
SAFETY .................................................................................................................................................. 3
OPERATION ...................................................................................................................................... 4
MAINTENANCE ................................................................................................................................. 5
INTRODUCTION ..................................................................................................................................... 7
EXCAVATOR COMPATIBILITY ............................................................................................................... 7
MODEL SPECIFICATIONS ..................................................................................................................... 8
SERIAL NUMBER LOCATION .............................................................................................................. 20
U21J/JR, U31J/JR, U45J/JR ............................................................................................................. 20
G7, G18J, G26J ................................................................................................................................ 21
G30JR .............................................................................................................................................. 22
CRUSHER BOOSTER & CYLINDER ..................................................................................................... 23
INTRODUCTION .............................................................................................................................. 23
STRUCTURE OF THE BOOSTED CYLINDER .................................................................................. 24
OPERATING PRINCIPLE ................................................................................................................. 25
HYDRAULIC INSTALLATION ................................................................................................................ 32
HYDRAULIC KITS ............................................................................................................................ 32
FLOW DIRECTION ........................................................................................................................... 32
SHUT-OFF VALVES ......................................................................................................................... 33
TEST PORT LOCATIONS ................................................................................................................ 33
PREVENTION OF CONTAMINATION .............................................................................................. 35
HYDRAULIC QUICK DISCONNECTS ............................................................................................... 36
MOUNTING INSTALLATION ................................................................................................................. 38
MOUNTING TO THE CARRIER ........................................................................................................ 39
REMOVAL FROM THE CARRIER .................................................................................................... 40
STORAGE OF THE CRUSHER ............................................................................................................. 40
HOSE INSTALLATION .......................................................................................................................... 41
WHIP HOSE INSTALLATION TIPS ................................................................................................... 41
OPERATING INSTRUCTIONS .............................................................................................................. 43
OPERATING TECHNIQUES AND PRECAUTIONS ............................................................................... 45
GENERAL MAINTENANCE ................................................................................................................... 48
DAILY INSPECTION AND MAINTENANCE ...................................................................................... 48
LUBRICATION POINTS.................................................................................................................... 49
HOSE INSTALLATION TIPS ............................................................................................................. 51
CUTTER BLADE MAINTENANCE .................................................................................................... 53
JAW INSPECTION AND MAINTENANCE.............................................................................................. 56
WEEKLY INSPECTION .................................................................................................................... 56
MINIMUM DISTANCE BETWEEN FIXED AND MOVEABLE JAW ...................................................... 56
TEETH MAINTENANCE AND REPLACEMENT .................................................................................. 58
MOVEABLE JAW BUILDUP AND HARDFACING ............................................................................... 58
TEETH REPLACEMENT .................................................................................................................. 59
REPLACEABLE TOOTH PLATES – MOVEABLE JAWS ................................................................... 60
REPLACEABLE TOOTH PLATES – MAIN FRAME ........................................................................... 60
JAW AND TOOTH REBUILD PROCEDURE: ALL MODELS ............................................................. 61
JAW CONTACT AREAS ................................................................................................................... 63
MAIN FRAME REWORK GUIDE ........................................................................................................... 64
FRAME MAINTENANCE – REPAIR OF MAIN FRAME .......................................................................... 65
ROUTE WELD REPAIR .................................................................................................................... 65
INSPECTION AND MAINTENANCE ...................................................................................................... 67
BOOSTER CYLINDER ..................................................................................................................... 67
CYLINDER COMPONENTS ............................................................................................................. 70
REPAIR TOOLS AND EQUIPMENT.................................................................................................. 72
TOP BRACKET CONVERSION ............................................................................................................. 79
CONVERSION PACKAGES OFFERED FOR “U” SERIES CRUSHERS ............................................ 79
SLEWING RING INSPECTION AND MAINTENANCE ........................................................................... 80
MEASURING MAXIMUM AXIAL MOVEMENT................................................................................... 80
ROTATION BEARING OUTER DIRT SEAL REPLACEMENT ............................................................ 81
CRUSHER RELIEF LOCATIONS .......................................................................................................... 81

2
CONTENTS
U21J, U21JR, U31J, U31JR, U45J, U45JR, G30JR ........................................................................... 82
G7, G18J, G26J ................................................................................................................................ 82
SWIVEL MANIFOLD MAINTENANCE ................................................................................................... 84
SWIVEL MANIFOLD ASSEMBLY ..................................................................................................... 84
LEAKAGE OF THE SEALS ............................................................................................................... 84
TESTING THE SWIVEL SEALS FOR INTERNAL LEAKAGE ............................................................. 84
REPLACEMENT OF THE SEALS IN THE SWIVEL ........................................................................... 85
FASTENER TORQUE SPECIFICATIONS ............................................................................................. 88
HOSE TORQUE SPECIFICATIONS ...................................................................................................... 95
JIC ENDS ......................................................................................................................................... 95
ORFS ENDS .................................................................................................................................... 95
TROUBLESHOOTING ........................................................................................................................... 96
RELIEF VALVE LOCATION ............................................................................................................ 102
KEYWORDS FOR COMMON CRUSHER COMPONENTS .................................................................. 116
KEYWORDS FOR COMMON CRUSHER CYLINDER COMPONENTS ............................................... 117
WARRANTY STATEMENTS ............................................................................................................... 118

3
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.
WARNING – FALLING OR FLYING DEBRIS decals are included with each NPK
CONCRETE CRUSHER. The decal must be installed in the cab, visible to the operator.
WARNING - STAY CLEAR decals are installed on all NPK CONCRETE CRUSHERS.
Keep them clean and visible. NPK will provide decals free of charge as needed.
FALLING OR FLYING DEBRIS decal is included
with each NPK CONCRETE CRUSHER. The
decal (part number H100-7210) must be installed
in the cab, visible to the operator.
STAY CLEAR decal (part number H100-7200) is
installed on all NPK CONCRETE CRUSHERS,
Shears, and Material Processors. Keep them
clean and visible. NPK will provide decals free of
charge as needed.

4
Warning Decal for Cab Installation
SAFETY
OPERATION
1. Operator personnel must read and understand the NPK INSTRUCTION MANUAL
to prevent serious or fatal injury.
2. FLYING OR FALLING DEBRIS CAN CAUSE SERIOUS OR FATAL INJURY.
Keep personnel and bystanders clear of the CONCRETE CRUSHER while in
operation.
3. Do not operate CONCRETE CRUSHER without
an impact resistant shield between the
CONCRETE CRUSHER and operator. Operate
with extreme caution near walls or columns that
may collapse and near concrete and debris that
may fall.
4. Operate the CONCRETE CRUSHER from the
operator’s seat only.
5. Use two people whenever operator visibility is
limited, one to operate the CONCRETE
CRUSHER, the other to guide operations.
6. Do not leave a load suspended in air.
7. Do not pass a load over people, vehicles, etc.
8. Do not operate the CONCRETE CRUSHER
within reach of power lines.
9. Do not climb, sit, or ride on the CONCRETE CRUSHER.
10. Match the CONCRETE CRUSHER size to excavator according to NPK
recommendations. The excavator must be stable during CONCRETE CRUSHER
operation and during transport. See CARRIER COMPATIBILITY section of the
NPK instruction manual.
11. Do not operate without inspection (access) covers in place.
12. Be especially cautious around hydraulic lines. Hydraulic oil can be extremely HOT!
Avoid skin contact with hydraulic oil. It can cause severe burns!
13. 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 pressure before disconnecting any lines. Search for leaks with a piece of
cardboard, or other object. If an accident occurs, see a doctor immediately!
Hydraulic fluid injected into the skin must be surgically removed within a few hours
or gangrene may result.
14. The pressure generated by the power intensifier on the CONCRETE CRUSHER
exceeds 10,000 psi (690 bar), which is higher than commonly encountered on
hydraulic equipment. To avoid bodily harm and/or injury when conducting
inspection checks, use gauges, hoses and fittings rated at 15,000 psi (1035 bar).
For parts replacement, use only genuine NPK replacement parts. Contact NPK
Service Department at 1-800-225-4379.
15. When removing or installing mounting pins, beware of flying metal chips.

5
SAFETY
MAINTENANCE
1. Use only NPK supplied replacement parts. NPK specifically disclaims any
responsibility for bodily injury or CONCRETE CRUSHER damage that results from
the use of parts not sold or approved by NPK.
2. Use extreme caution in handling. A fully assembled CONCRETE CRUSHER can
weigh up to 5 tons (4-1/2 tonnes). Sub-assemblies range in weight from hundreds
to thousands of pounds. To avoid bodily harm, use lifting and securing
mechanisms of adequate capacity to support loads. Seek the aid of an assistant
as much as possible, and always when handling heavier sub-assemblies.
3. Use extreme caution when changing jaw sets, particularly in the field. Employ
lifting and securing mechanisms of adequate capacity to support the jaw sets. At
least two people are required to change a jaw set safely in the field.
4. Wear safety glasses and protective clothing when working on the CONCRETE
CRUSHER. Wear thermal-protective gloves when handling heated parts.
5. Prevent exposure to hazardous fumes. Remove all paint, grease, and oil before
heating, cutting, or welding on the CONCRETE CRUSHER.
6. Be especially cautious around hydraulic lines. Hydraulic oil can be extremely HOT!
Avoid skin contact with hydraulic oil. It can cause severe burns!
7. Protect hands and body from hydraulic
fluids under pressure. Escaping fluid under
pressure can penetrate the skin, causing
serious injury. Avoid the hazard by relieving
pressure before disconnecting any lines.
Search for leaks with a piece of cardboard, or
other object. If an accident occurs, see a
doctor immediately! Hydraulic fluid injected
into the skin must be surgically removed
within a few hours or gangrene may result!
8. The pressure generated by the power intensifier on the CONCRETE CRUSHER
exceeds 10,000 psi (690 bar), which is higher than commonly encountered on
hydraulic equipment. To avoid bodily harm and/or injury when conducting
inspection checks, use gauges, hoses and fittings rated at 15,000 psi (1035 bar).
For parts replacement, use only genuine NPK replacement parts. Contact NPK
Service Department at 1-800-225-4379.
9. When removing or installing mounting pins, beware of flying metal chips.

6
SAFETY
MAINTENANCE
STANDARD PRACTICES
Maintenance of and repairs to the CONCRETE CRUSHER 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
foreign contaminants. Thoroughly clean the work area.
 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.
 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 specified 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
CONCRETE CRUSHER.
ATTENTION

7
INTRODUCTION
Thank you for your purchase of an NPK attachment. NPK prides itself in the design and
manufacture of high quality attachments. The quality workmanship and materials,
which go into all of our attachments, will provide maximum service life. With proper
care, and use, your NPK attachment should provide you with many years of productive
service.
The purpose of this manual is to provide you with information and instructions required
to properly operate and maintain the CONCRETE CRUSHER. This will result in
maximum ATTACHMENT reliability and productivity.
Read this manual thoroughly before attempting to operate, remove, disassemble,
repair, or troubleshoot the CONCRETE CRUSHER or any of its components. For
additional information or help with any problem encountered, please contact your
authorized NPK dealer.
Follow all the safety precautions contained in this manual. Failure to follow safety
precautions can result in death, personal injury, injury to others and property
damage.
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.
EXCAVATOR 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 CONCRETE CRUSHER that is too heavy for the carrier can be dangerous
and damage the carrier. Verify carrier stability with the CONCRETE CRUSHER before
transport or operation.
Mounting a CONCRETE CRUSHER that is too small for the carrier can damage the
CONCRETE CRUSHER and void warranties. Please consult NPK Service or
Engineering for specific detailed information.
CRUSHER
RECOMMENDED CARRIER WEIGHT RANGE
MODEL
3rd member mounting
US ton
(Metric ton)
U21J
21 - 31
(19 - 28)
U21JR
21 - 31
(19 - 28)
U31J
31 - 53
(28 - 48)
U31JR
31 - 53
(28 - 48)
U45J
45 - 55
(41 - 50)
U45JR
45 - 55
(41 - 50)
G7
6.6 - 11
(6 - 10)
G18J
20 - 25
(18 - 23)
G26J
25 - 35
(23 - 32)
G30JR
35 - 50
(32 - 45)
Specifications subject to change without notice.

8
MODEL SPECIFICATIONS
U21J SECONDARY
CONCRETE CRUSHER
MODEL
Weight
Maximum Jaw
Oil Flow
Cycle Time
Opening
(seconds)
lb.
(kg)
in.
(mm)
gpm
(lpm)
open
close
U21J
4,650
(2,110)
31.6
(802.4)
26-53
(98-200)
1.2
1.6
MODEL
Maximum
Crushing Force
Crushing Force
Operating
Pressure
at d86
at d87
US
(Metric
US
(Metric
psi
(bar)
Ton
Ton)
Ton
Ton)
U21J
3,771
(260)
73
(66)
100
(90)
Specifications subject to change without notice.
Cycle time is full stroke at maximum flow.
Carrier flow is set at minimal operating pressure of 1000 psi (69 bar).
*Maximum operating pressure is determined by reliefs in the crusher.

9
MODEL SPECIFICATIONS
U21JA SECONDARY
CONCRETE CRUSHER
MODEL
Weight
Maximum Jaw
Oil Flow
Cycle Time
Opening
(seconds)
lb.
(kg)
in.
(mm)
gpm
(lpm)
open
close
U21JA
4,650
(2,110)
31.6
(802.4)
26-53
(98-200)
1.2
1.6
MODEL
Maximum
Crushing Force
Crushing Force
Operating
Pressure
at d86
at d87
US
(Metric
US
(Metric
psi
(bar)
Ton
Ton)
Ton
Ton)
U21JA
3,771
(260)
73
(66)
100
(90)
Specifications subject to change without notice.
Cycle time is full stroke at maximum flow.
Carrier flow is set at minimal operating pressure of 1000 psi (69 bar).
*Maximum operating pressure is determined by reliefs in the crusher.