Machine manual

en-PM.RUN.003.B

Maintenance of POLYCOM® roll bodies with studs

Code Word
MARWAL

Order Number
D000766

Plant Order Code (POC)

8F1.PM02
en-PM.RUN.003.B Contents
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Maintenance of POLYCOM roll bodies with studs

Contents

1 Safety ..................................................................................................... 1-1

2 Technical data ....................................................................................... 2-1
3 Components and description of functioning..................................... 3-1
3.1 Components ........................................................................................... 3-1
3.2 Description of functioning ..................................................................... 3-14
4 Transportation and assembly ............................................................. 4-1
4.1 Transport and storage instructions ......................................................... 4-1
5 Lubrication ............................................................................................ 5-1
6 Commissioning ..................................................................................... 6-1
6.1 Checks prior to commissioning .............................................................. 6-1
6.2 Setting and adjustment ........................................................................... 6-1
7 Operation ............................................................................................... 7-1
8 Maintenance .......................................................................................... 8-1
8.1 Safety instructions .................................................................................. 8-1
8.2 Inspection ............................................................................................... 8-2
8.2.1 Inspections of the roll bodies .................................................................. 8-2
8.2.2 Wear limits .............................................................................................. 8-2
8.3 Repair ..................................................................................................... 8-8
8.3.1 Replacing damaged studs (2.0) ........................................................... 8-10
9 Spare parts ............................................................................................ 9-1
9.1 Suggestions for enquiries and orders of spare parts ............................. 9-1
10 Appendix ............................................................................................. 10-1
10.1 Technical drawings ............................................................................... 10-1
10.2 Special tools ......................................................................................... 10-1
10.3 Subsuppliers' documentation ............................................................... 10-1
en-PM.RUN.003.B Safety
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Maintenance of POLYCOM roll bodies with studs 1-1

1 Safety
Use
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● The roll unit is a component of the high-pressure grinding roll POLYCOM .
Be sure to comply with the specification of the intended use in the section
Technical data.
● Any use other than the intended use is forbidden. thyssenkrupp Industrial
Solutions is not responsible for damage resulting from any use other than the
intended use. This risk shall be borne exclusively by the plant owner.
● The intended use also includes observance of the machine manual and
compliance with the maintenance instructions.
Transport and assembly
● All transportation instructions in this machine manual refer exclusively to
transportation of the machine on the plant site.
● Only use suitable lifting machinery and lifting accessories which are in perfect
working order and have a sufficient load-bearing capacity.
● Take special care with the transportation of gear units already equipped with
oil pumps and piping. Before transporting gear units, remove the piping and
close all pipe sockets and openings with weather-proof and impact-proof
sealing covers to prevent ingress of tramp material.
● Never work under a suspended load.
Operation
● Any safety checks before or during operation depend on the relevant national
regulations. The owner is responsible for the performance and recording of
such checks.
● If safety-relevant changes in the machine or its operating behaviour occur,
shut it down immediately.
● Hearing protectors must be worn in the vicinity of the mill, as the noise level
exceeds 90 dB (A).
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● To protect the drives, the POLYCOM high-pressure grinding roll must not be
started if there is mill feed material in the roll gap and the floating roll is
pressed against the fixed roll.
● Be sure to comply with the information contained in the machine manual for
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the POLYCOM high-pressure grinding roll about the special conditions for
starting the high-pressure grinding roll with hot material.
Safety en-PM.RUN.003.B
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1-2 Maintenance of POLYCOM roll bodies with studs

Maintenance
● Be sure to also comply with the safety instructions in the machine manuals for
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the POLYCOM high-pressure grinding roll.
● Make absolutely sure that all machines and motors whose operation might
endanger persons or equipment are switched off and secured against
restarting for the entire duration of the maintenance work.
● Make absolutely sure that all rotating parts of the machine have come to a
complete standstill before you remove any protection devices or open any
covers.
● The plant owner must ensure that all rotating parts are protected against
accidental contact.
● Before performing any work on the machine, make sure that there is no
danger of suffering burns when touching it, and before opening any inspection
and service covers, make certain that there is no longer any hot material
inside the machine.
● Keep the machine free of oily and flammable substances and materials. Never
use gasoline or other easily flammable substances for cleaning the machine.
● Switch off the power supply to all electrical components before beginning any
maintenance work.
● Make absolutely sure that the pneumatic piping is relieved of pressure before
disconnecting it.
● Before carrying out work on the central lubrication system with pneumatically
operated grease pump, you must disconnect the grease pump from the
compressed-air supply system.
● Close the shut-off devices for lubricant supply after you have shut down the
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POLYCOM high-pressure grinding roll.
● Make absolutely sure that the piping of the central lubrication system is
relieved of pressure.
● If you carry out electric welding on any part of the machine, never conduct the
welding current through plain or antifriction bearings, other moving connecting
elements or measuring devices. Always directly connect the welding current
return lead to the part being welded.
● After finishing all maintenance work, check all joints and connections for leaks.
● Remount all protection devices when the maintenance work has been finished.
Make absolutely sure that no persons are inside the plant component before
you properly close the inspection and service covers.
en-PM.RUN.003.B Technical data
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Maintenance of POLYCOM roll bodies with studs 2-1

2 Technical data
Specification of the intended use
See the machine manual for the High- No. PM.CPT.001
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pressure grinding roll POLYCOM
2
Permissible specific loading (grinding 4.29 N/mm
force / roll width X diameter)

Permissible feed size 40 mm

Roll diameter 2400 mm

Roll width 1650 mm

Design of the roll body surface

Number of studs per roll, in total (m+n) = 12350

Marking of the studs P12 / P15

Length of the studs 40 mm

Diameter of the studs 22 mm

Edge zone
Number of studs per roll n = 520

Marking of the studs P15

Length of the studs 40 mm

Diameter of the studs 22 mm

Middle zone
Number of studs per roll m = 11830

Marking of the studs P12

Length of the studs 40 mm

Diameter of the studs 22 mm

Technical data en-PM.RUN.003.B
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2-2 Maintenance of POLYCOM roll bodies with studs

Types of side wear protection

Type I [ not installed ] Hardfaced edge-side wear protection
(3.1)

Type II a [ not installed ] Bolted edge-side wear protection (3.2)

Type II b [ not installed ] Bolted edge-side wear protection (3.2)

Type II c [ not installed ] Bolted edge-side wear protection (3.2)

Type III Bonded-in edge blocks with plug-

welded side wear protection (3.3)

Tightening torque of hexagon socket -

head screw

Number of edge blocks per roll 368

Number of side wear protection 24

segments per roll

Permissible degrees of wear

Wear of stud amaxs = 30 - 35 mm

Wear of roll body amaxw = 25 - 30 mm

Wear of edge weld -

Wear of hard metal edge block amaxE = 25 mm

en-PM.RUN.003.B Technical data
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Maintenance of POLYCOM roll bodies with studs 2-3

Representation of different degrees of hardness

Fig. 1

m = hard studs in the middle zone

n = softer studs in the edge zone
en-PM.RUN.003.B Components and description of functioning
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Maintenance of POLYCOM roll bodies with studs 3-1

3 Components and description of functioning

3.1 Components

Some details of the drawings in this manual may not be identical to the drawings
of the actually delivered machine.
Components and description of functioning en-PM.RUN.003.B
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3-2 Maintenance of POLYCOM roll bodies with studs

Fig. 2: Roll
en-PM.RUN.003.B Components and description of functioning
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Maintenance of POLYCOM roll bodies with studs 3-3

No. Denomination

1.0 Roll body

2.0 Stud

3.0 Edge-side wear protection

Components and description of functioning en-PM.RUN.003.B
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3-4 Maintenance of POLYCOM roll bodies with studs

Types of edge-side wear protection

Different versions are used for the different types of edge-side wear protection:

Type I - Welded-on edge-side wear protection (3.1)

Fig. 3: Edge-side wear protection type I

en-PM.RUN.003.B Components and description of functioning
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Maintenance of POLYCOM roll bodies with studs 3-5

No. Denomination

1.0 Roll body

2.0 Stud

3.1.1 Metal strips with hard metal coating

3.1.2 Side wear protection segment, plug-welded

3.1.3 Plug weld with hard weld layer

Components and description of functioning en-PM.RUN.003.B
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3-6 Maintenance of POLYCOM roll bodies with studs

Type II a - Bolted edge-side wear protection (3.2) with hard weld layer

Fig. 4: Edge-side wear protection type II a

en-PM.RUN.003.B Components and description of functioning
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Maintenance of POLYCOM roll bodies with studs 3-7

No. Denomination

1.0 Roll body

2.0 Stud

3.2.1 Bolted edge-side wear protection segment with hard weld layer

3.2.3 Hexagon socket head screw

Components and description of functioning en-PM.RUN.003.B
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3-8 Maintenance of POLYCOM roll bodies with studs

Type II b - Bolted edge-side wear protection (3.2) with TPC coating

Fig. 5: Edge-side wear protection type II b

en-PM.RUN.003.B Components and description of functioning
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Maintenance of POLYCOM roll bodies with studs 3-9

No. Denomination

1.0 Roll body

2.0 Stud

3.2.2 Bolted edge-side wear protection segment with TPC coating

3.2.3 Hexagon socket head screw

Components and description of functioning en-PM.RUN.003.B
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3-10 Maintenance of POLYCOM roll bodies with studs

Type II c - Bolted edge-side wear protection (3.2) with brazed-on edge blocks

Fig. 6: Edge-side wear protection type II c

en-PM.RUN.003.B Components and description of functioning
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Maintenance of POLYCOM roll bodies with studs 3-11

No. Denomination

1.0 Roll body

2.0 Stud

3.2.3 Hexagon socket head screw

3.2.4 Side wear protection segment, bolted

3.2.5 Edge block, brazed

Components and description of functioning en-PM.RUN.003.B
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3-12 Maintenance of POLYCOM roll bodies with studs

Type III - Bonded-in edge blocks with plug-welded side wear protection (3.3)

Fig. 7: Edge-side wear protection type III

en-PM.RUN.003.B Components and description of functioning
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Maintenance of POLYCOM roll bodies with studs 3-13

No. Denomination

1.0 Roll body

2.0 Stud

3.3.1 Edge block, bonded-in

3.3.2 Side wear protection segment, plug-welded

3.3.3 Plug weld with hard weld layer

Components and description of functioning en-PM.RUN.003.B
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3-14 Maintenance of POLYCOM roll bodies with studs

3.2 Description of functioning

The roll surface of the roll body (1.0) is equipped with studs (2.0). The studs (2.0)
can have different diameters, lengths and hardnesses depending on their
application. The different marking on the top side shows the different hardnesses
of the studs (2.0).
The face sides of the roll bodies are provided with edge-side wear protection (3.0)
which differs in design, depending on the application.
The roll body (1.0) is shrink-fitted onto a shaft.
en-PM.RUN.003.B Transportation and assembly
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Maintenance of POLYCOM roll bodies with studs 4-1

4 Transportation and assembly

4.1 Transport and storage instructions
The studs (2.0) have to be stored in their original packaging, in order to prevent
studs of different hardnesses from being mixed up. For better distinction, the
studs (2.0) are provided with marks on their surface.
The adhesive for the studs (2.0) has to be stored in accordance with the
manufacturer's instructions.
The filler metals must be stored with suitable protection against moisture and in a
temperature-controlled environment. Also be sure to comply with the
manufacturer's storage instructions.
en-PM.RUN.003.B Lubrication
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Maintenance of POLYCOM roll bodies with studs 5-1

5 Lubrication
This machine/unit requires no lubrication.
en-PM.RUN.003.B Commissioning
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Maintenance of POLYCOM roll bodies with studs 6-1

6 Commissioning
It is a prerequisite for our warranty that the commissioning is carried out in the
presence of specialists from thyssenkrupp Industrial Solutions and in
accordance with their instructions.

6.1 Checks prior to commissioning

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Prior to the test run of the POLYCOM high-pressure grinding roll, be sure to
check the high-pressure grinding roll, the drive and the material feed system, as
well as the electrical interlock of the complete plant. Furthermore, make
absolutely sure that all material remnants, tools and assembly appliances are
removed from the mill. For more detailed information about the interlock system,
see the section Operation.

CAUTION
Tramp material
The wear protection of the rolls may be damaged by tramp material.
For the arrangement and operation of the magnetic separator and the
metal detector, strictly observe the corresponding information and
directives.

Maximum permissible tramp material size:

Roll diameter [mm] Maximum edge length [mm]

up to 2000 15

greater than 2000 20

6.2 Setting and adjustment

See the machine manual for the high-pressure grinding roll.

Too wide a gap between the feed material guide plate and the roll end face
causes lateral wear on the rolls. Make absolutely sure that the gap width is 5
mm.
en-PM.RUN.003.B Operation
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Maintenance of POLYCOM roll bodies with studs 7-1

7 Operation
CAUTION

For the permissible compression stress of the rolls' wear protection and
therefore the pressure in the roll gap, see the section Technical data.
To protect the drives, the main motors must not be started if there is feed
material in the roll gap and the floating roll is pressed against the fixed
roll.
en-PM.RUN.003.B Maintenance
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Maintenance of POLYCOM roll bodies with studs 8-1

8 Maintenance
8.1 Safety instructions
DANGER
The noise level exceeds 90 dB(A) in the mill area.
Your hearing could be damaged.
Always wear hearing protectors in the vicinity of the mill.

DANGER
It is forbidden to carry out work at rotating roll units.
You could be very severely injured.
I. The owner of the plant has to ensure that the whole area of the high-
pressure grinding roll is secured, such that it is impossible for persons
to come into contact with rotating parts.
II. Make absolutely sure that all rotating parts of the machine have come
to a complete standstill before you remove any protection devices or
open any covers.

DANGER
When the mill is switched off, it does not stop immediately.
You could be killed or parts of your body could be severed.
I. Let the mill swing to a complete stop.
II. Secure the mill to prevent turning.

DANGER
The high-pressure grinding roll may be hot.
You may suffer very severe burns!
Let the mill cool down.

DANGER
The material in the mill can fall down or give way.
You could be buried alive or sink into the material.
I. Make absolutely sure that there are no coatings of material in the mill
or in the inlet.
II. Make absolutely sure that the mill feed material has an adequate load-
bearing capacity, or cover the mill feed material with suitable auxiliary
equipment.

After you have completed the repair work, you must check the machine/plant
again in accordance with the section Checks prior to commissioning.
Maintenance en-PM.RUN.003.B
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8-2 Maintenance of POLYCOM roll bodies with studs

8.2 Inspection

8.2.1 Inspections of the roll bodies

The frequency of inspections depends on the abrasiveness of the material. We

recommend a weekly check in the beginning. If the wear is lower, the interval
between the checks can be extended to a useful interval. Wear measurement is,
however, necessary after every 1000 operating hours at the latest.

No. Work to be performed Frequency Remarks

1 Check the studs (2.0) Weekly

2 Measure the wear on the roll Weekly

surfaces between the studs (2.0)

3 Check the edge-side wear protection Weekly

(3.0)

8.2.2 Wear limits

The wear measurement is based on the measurement record that was prepared
during commissioning.

The wear measurement provides information about the following necessary

adaptations to the high-pressure grinding roll. See the machine manual for the
High-pressure grinding roll.

Wear on the studs

A criterion for the permissible wear of the studs (2.0) is the necessary residual
length of the studs (2.0) in the roll body. When the degree of wear “amaxw or amaxs”
specified in the section Technical data has been reached, the roll body (1.0) must
be replaced or refurbished.

The difference in diameter between the floating roll and the fixed roll must not
o
exceed 2 /oo.

Wear between the studs (2.0)

In new condition, the studs (2.0) protrude approx. 5 mm above the base metal of
the roll body (1.0). According to experience, an identical wear rate is adjusted at
the studs (2.0) and between the studs (2.0) at the base metal.
If the base metal wears out faster, the studs (2.0) project higher above the base
metal. This wear profile may cause a higher breakage rate of the studs (2.0). If
the breakage rate is too high due the higher stud projection, the roll body (1.0)
must be replaced.
en-PM.RUN.003.B Maintenance
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Maintenance of POLYCOM roll bodies with studs 8-3

Edge wear on rolls with welded edge-side wear protection (3.1)

The stud projection above the base metal and the thickness of the hardfacing
applied in the edge zone of the roll surface are identical in new condition. With
increasing wear, there should be no difference in the height of the two surfaces. If
a difference in height of ≥ 3 mm is measured during the wear measurement
intervals, the metal strip with hard metal coating (3.1.1) must be replaced.

Edge wear on rolls with bolted edge-side wear protection (3.2)

When the maximum degree of wear has been reached, the edge-side wear
protection must be replaced.

Edge-side wear protection on rolls with bonded-in edge blocks and plug-welded side
wear protection (3.3)
Destroyed edge blocks (3.3.1) must be replaced. Replacement is necessary
when the specified wear limits have been reached.

Too wide a gap between the feed material guide plate and the roll end face
causes lateral wear on the rolls. Make absolutely sure that the gap width is
5 mm.
Maintenance en-PM.RUN.003.B
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8-4 Maintenance of POLYCOM roll bodies with studs

Type I - Welded-on side wear protection (3.1)

Fig. 8: Edge-side wear protection type I

XOs = Dimension in the case of a new roll, measured to the upper edge of the studs

XOw = Dimension in the case of a new roll, measured to the upper edge of the roll body

XOR = Dimension in the case of a new roll, measured to the upper edge of the edge weld

Xmaxs = XOs+amaxs = Dimension with maximum permissible wear of the studs

Xmaxw = XOw+amaxw = Dimension with maximum permissible wear of the roll body
between the studs

XmaxR = XOR+amaxR = Dimension with maximum permissible wear of the edge weld

M = Measuring
strip
en-PM.RUN.003.B Maintenance
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Maintenance of POLYCOM roll bodies with studs 8-5

Type II a-b - Bolted edge-side wear protection (3.2)

Fig. 9: Side wear protection type II a-b

XOs = Dimension in the case of a new roll, measured to the upper edge of the studs

XOw = Dimension in the case of a new roll, measured to the upper edge of the roll body

XOR = Dimension in the case of a new roll, measured to the upper edge of the edge weld

Xmaxs = XOs+amaxs = Dimension with maximum permissible wear of the studs

Xmaxw = XOw+amaxw = Dimension with maximum permissible wear of the roll body
between the studs

XmaxR = XOR+amaxR = Dimension with maximum permissible wear of the edge weld

M = Measuring
strip
Maintenance en-PM.RUN.003.B
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8-6 Maintenance of POLYCOM roll bodies with studs

Type II c - Bolted edge-side wear protection (3.2) with brazed-on edge blocks

Fig. 10: Side wear protection type II c

XOs = Dimension in the case of a new roll, measured to the upper edge of the studs

XOw = Dimension in the case of a new roll, measured to the upper edge of the roll body

XOE = Dimension in the case of a new roll, measured to the upper edge of the edge
blocks

Xmaxs = XOs+amaxs = Dimension with maximum permissible wear of the studs

Xmaxw = XOw+amaxw = Dimension with maximum permissible wear of the roll body
between the studs

XmaxE = XOE+amaxE = Dimension with maximum permissible wear of the edge blocks

M = Measuring
strip
en-PM.RUN.003.B Maintenance
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Maintenance of POLYCOM roll bodies with studs 8-7

Type III - Bonded-in edge blocks with plug-welded side wear protection (3.3)

Fig. 11: Side wear protection type III

XOs = Dimension in the case of a new roll, measured to the upper edge of the studs

XOw = Dimension in the case of a new roll, measured to the upper edge of the roll body

XOE = Dimension in the case of a new roll, measured to the upper edge of the edge
blocks

Xmaxs = XOs+amaxs = Dimension with maximum permissible wear of the studs

Xmaxw = XOw+amaxw = Dimension with maximum permissible wear of the roll body
between the studs

XmaxE = XOE+amaxE = Dimension with maximum permissible wear of the edge blocks

M = Measuring
strip
Maintenance en-PM.RUN.003.B
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8-8 Maintenance of POLYCOM roll bodies with studs

8.3 Repair

Required personnel
To ensure correct performance of the work, only assign it to personnel that have
received special training for the tasks to be performed.

Required tools
Special tools are required (see the List of special tools).
Whether or not you need auxiliary equipment, such as scaffolds or lifting
machinery, depends on the circumstances at your plant.

General
Before beginning any repair work, switch off the power supply to all electrical
components.
Do not remove or open any covers or protection devices until all rotating parts
have come to a complete standstill.
Ensure absolute cleanliness at all times during the repair work, in order to prevent
dirt from entering the bearings, the drives, the hydraulic system or other sensitive
parts of the machine or plant.
The plant owner is responsible for the safe and environment-friendly disposal of
all consumables and process materials, as well as of exchange parts.

After you have completed the repair work, you must check the machine/plant
again in accordance with the section Preparation for test run in the machine
manual for the high-pressure grinding roll.

Replacing the plug-welded side wear protection segments (type I and III)
● Remove the plug weld (3.1.3 or 3.3.3) by means of an angle grinder.
● Remove the side wear protection segments (3.1.2 or 3.3.2) if necessary by
means of a suitable lever.
● Remove welding residues from the roll body by means of a grinder.
● Weld on new side wear protection segments (3.1.2 or 3.3.2) by means of plug
welding.
● Cover the plug weld with a hard layer.

Replacing the bolted edge-side wear protection segments (type II)

● Unscrew the hexagon socket head screws (3.2.3) and remove the edge-side
wear protection segments (3.2.1 and 3.2.2).
● Bolt on the new edge-side wear protection segments (3.2.1 and 3.2.2), tighten
the hexagon socket head screws (3.2.3) to a torque according to the drawing
supplied under the contract.
en-PM.RUN.003.B Maintenance
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Maintenance of POLYCOM roll bodies with studs 8-9

Replacing bonded-in edge blocks (type III)

Replacement is necessary when the wear limits have been reached or the edge
blocks are damaged.

WARNING
When removing edge blocks by heating up the surrounding area in order
to incinerate the adhesive, it is possible that air inclusions in the drill
holes underneath the edge blocks and the adjacent studs will expand and
that the resultant pressure will cause individual edge blocks or studs to
shoot out.
You could suffer severe injuries.
If you heat up any areas of the roll surface, you must not stand directly
adjacent to the heated area. The working area must be cordoned off.

● Heat the respective edge block(s) and the corresponding roll body area in
order to dissolve the adhesive (180-200 °C).

Never heat adjacent studs (2.0). Otherwise, the bond of adjacent studs (2.0)
may be destroyed.

● Withdraw the blocks.

● Remove residual adhesive and contaminations from the contact surface and
the location hole. Surfaces must be bright.
● Clean the drill hole with Loctite 7063 cleaner.
● Put 2-3 drops of Loctite 638 into the drill hole.
● Insert new edge block and press into the drill hole until the contact surface is
reached.

The edge-side wear protection (3.0) may only be replaced if it was damaged in
relatively new condition by the entry of tramp metal. The service life of the edge-
side wear protection (3.0) is matched to the service life of the roll bodies.
Maintenance en-PM.RUN.003.B
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8-10 Maintenance of POLYCOM roll bodies with studs

8.3.1 Replacing damaged studs (2.0)

Purpose
Damage to the hard metal studs may be caused by tramp metal, for example.
Replacement of individual studs (2.0) may become necessary. Studs (2.0) must
be replaced if adjacent studs (2.0) are affected and if excessive wear is
determined in the vicinity of damaged studs (2.0).
The following description includes:
● the removal of damaged studs (step 1 to 5)
● the preparation for gluing-in new studs ( step 6 to 8)
● the gluing-in of studs (step 9 to 11)
Required tools
● Wire brush
● Welding torch
● Brazing filler metal: DIN 8513 L-AG 30 Cd ISO 3677 B Ag 30 Cu Zn Cd
● Extraction device
● Holder for extraction device (with magnetic foot)
● Cleaning tool for the drill hole
● Loctite 7063 cleaner
● Loctite 638 adhesive
en-PM.RUN.003.B Maintenance
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Maintenance of POLYCOM roll bodies with studs 8-11

Step 1: Clean the roll surface in the vicinity of the stud (2.0) with a wire brush. The
use of a needle hammer has proven effective in cases in which the mill feed
material is very tightly pressed into the spaces between the studs (2.0).
Step 2: Grind the stud (2.0) until it is bright (with portable grinder).

CAUTION
When removing studs (2.0) by heating up the surrounding area in order to
incinerate the adhesive, it is possible that air inclusions in the drill holes
underneath the studs (2.0) and adjacent edge blocks will expand and that
the resultant pressure will cause individual studs (2.0) or edge blocks to
shoot out.
You could suffer severe injuries!
If you heat up any areas of the roll surface, you must not stand directly
adjacent to the heated area. The working area must be cordoned off.

Step 3: Heat the studs (2.0) up to 180-200 °C.

Adjacent studs (2.0) and edge blocks should not be stressed unnecessarily at
an increased temperature.

The studs (2.0) are glued in. The adhesive is incinerated when it is heated up to
temperatures of 180-200 °C. Individual studs (2.0) can be heated by a welding
torch. The heat must be applied specifically to the stud (2.0) to be removed. Any
excessive heating of the adjacent areas must be avoided. Use a small burner
with a concentrated flame setting.
Step 4: Braze on an extraction device
Braze on an extraction device for withdrawing the studs (2.0) from the drill holes
using the applied heat. A burner with a somewhat smaller flame can be used for
this purpose. The brazing filler metal should be relatively thick. Thin brazing filler
metal can ingress into the gap between the studs (2.0) and the roll body (1.0) and
thus prevent any withdrawal.
Maintenance en-PM.RUN.003.B
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8-12 Maintenance of POLYCOM roll bodies with studs

Step 5: Withdraw the studs (2.0)

The stud (2.0) to be removed can be withdrawn by rotating the brazed-on
extraction device. Another withdrawal option may be provided by the use of a
water pump or pipe wrench, if there is a stud projection that is still sufficient.
en-PM.RUN.003.B Maintenance
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Maintenance of POLYCOM roll bodies with studs 8-13

Step 6: Clean the drill hole

Clean the drill hole (wall and bottom of the drill hole) of old adhesive residues.
The surface must be bright. A corresponding drill or suitable spike fitted with
abrasive paper can be used. It must be ensured that the drill hole is not widened
or damaged. Then clean the drill hole by means of a cleaning agent such as
trichloroethane (Loctite 7063). Residues must be blown out by means of
compressed air.

The surface must be bright. It is recommended to carry out this process manually,
in order to minimise the risk of damaging the drill hole.
Maintenance en-PM.RUN.003.B
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8-14 Maintenance of POLYCOM roll bodies with studs

Step 7: Use Loctite 7063, for example, in order to dissolve and remove the old
adhesive residues in the drill hole.

Step 8: Blow out residues in the drill hole by means of compressed air.
en-PM.RUN.003.B Maintenance
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Maintenance of POLYCOM roll bodies with studs 8-15

Step 9: Apply adhesive in the drill hole.

The adhesive Loctite 638 is applied in the drill hole in a sufficient quantity (a few
drops suffice). The stud is inserted into the drill hole using a rotary movement.
The stud (2.0) is properly fitted if the stud base is in contact with the bottom of
the drill hole and the entire excess adhesive was pressed out.

A few drops of Loctite 638 are quite sufficient in general.

Maintenance en-PM.RUN.003.B
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8-16 Maintenance of POLYCOM roll bodies with studs

Step 10: Insert the stud (2.0) into the drill hole using a rotary movement.

If the studs (2.0) are already worn, the lengths of the studs (2.0) to be newly
inserted must be adapted. Projection of the new studs (2.0) relative to the worn
ones is permissible (2 mm max.).

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Step 11: Following a hardening time of approximately one hour, the POLYCOM can
be restarted.
Step 12: After you have completed the repair work, you must check the
machine/plant again in accordance with the section Preparation for test run
in the machine manual for the high-pressure grinding roll.
en-PM.RUN.003.B Spare parts
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Maintenance of POLYCOM roll bodies with studs 9-1

9 Spare parts
9.1 Suggestions for enquiries and orders of spare parts

Spare parts can be enquired about and ordered via the Professional Spare
Parts Navigator (PSPN), the electronic spare parts catalogue from thyssenkrupp
Industrial Solutions.
en-PM.RUN.003.B Appendix
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Maintenance of POLYCOM roll bodies with studs 10-1

10 Appendix
10.1 Technical drawings
For drawing numbers, please refer to the table of contents of this folder.

10.2 Special tools

List of special tools

10.3 Subsuppliers' documentation

Designation Subsupplier

Induction coil not existing