Rolling Mill Operation Management Report.pdf
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Aug 30, 2025
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About This Presentation
This report provides a comprehensive review of rolling mill operation management in the steel industry, focusing on efficiency, productivity, and quality control. Rolling mills are complex production units that require precise coordination of manpower, equipment, and process parameters to ensure con...
Slide Content
Prepared By :
Eng. Adel Ezz
Elgarhy Steel Co.
ROLLING MILL
OPERATION
2024
Eng. Adel Ezz
Elgarhy Steel Co.
ROLLING MILL
OPERATION
2024
1
Table of Contents
1 Principal Elements of the Operation Management ............................................ 2
2 Technological Instruction on Preparation of Rolls ............................................ 5
2.1 Planning and Preparation during breakdown .............................................10
2.2 Pre-cautions to be Taken During Roll Changing .......................................11
2.3 Points/areas to be Checked after Roll Changing ........................................13
2.4 Starting the Mill After Major Roll Changing.............................................18
2.5 Examination of the Finished Products .......................................................22
2.5.1 Finished Product Defectives ...................................................................24
2.6 Net Yield of The Rolling Mill ....................................................................31
3 Safety Management of Rolling Mill ................................................................32
References ........................................................................................................34
Table of Contents
1 Principal Elements of the Operation Management ............................................ 2
2 Technological Instruction on Preparation of Rolls ............................................ 5
2.1 Planning and Preparation during breakdown .............................................10
2.2 Pre-cautions to be Taken During Roll Changing .......................................11
2.3 Points/areas to be Checked after Roll Changing ........................................13
2.4 Starting the Mill After Major Roll Changing.............................................18
2.5 Examination of the Finished Products .......................................................22
2.5.1 Finished Product Defectives ...................................................................24
2.6 Net Yield of The Rolling Mill ....................................................................31
3 Safety Management of Rolling Mill ................................................................32
References ........................................................................................................34
2
1 Principal Elements of the Operation Management
The following are the principal elements of the operation management in a
rolling shop:
1. Process Parameter Stability:
• Ensuring stability in rolling process parameters is crucial. This includes
monitoring factors like the optimum metal heating cycle, rolling temperature
range, rolling rhythm (time interval required for each unit (or stand) within
the rolling mill to process a piece of steel. Essentially, it’s the time it takes for
the unit to roll one steel product and then be ready to roll the next one.), speed,
reductions, and tensions during rolling.
• Regular checks on the working surface condition of rolls, roll fittings, and roll
cooling (or lubrication) conditions are essential.
• Descaling conditions on the metal surface also play a role in process stability.
Figure 2 Effective Roll Cooling System for Hot Rolling Mill.
Figure 1 Hydraulic Descaling
1 Principal Elements of the Operation Management
The following are the principal elements of the operation management in a
rolling shop:
1. Process Parameter Stability:
• Ensuring stability in rolling process parameters is crucial. This includes
monitoring factors like the optimum metal heating cycle, rolling temperature
range, rolling rhythm (time interval required for each unit (or stand) within
the rolling mill to process a piece of steel. Essentially, it’s the time it takes for
the unit to roll one steel product and then be ready to roll the next one.), speed,
reductions, and tensions during rolling.
• Regular checks on the working surface condition of rolls, roll fittings, and roll
cooling (or lubrication) conditions are essential.
• Descaling conditions on the metal surface also play a role in process stability.
Figure 2 Effective Roll Cooling System for Hot Rolling Mill.
Figure 1 Hydraulic Descaling
3
2. Process Control Instruments:
• Pyrometers, ammeters (load indicators), dynamometers, and tachometers are
used to control and regulate the rolling process.
• Hourly rolling schedules and continuous testing of intermediate samples help
adjust pass sequences and roll changes.
3. Preparatory Operations:
• Preparing billets for rolling involves adhering to schedules (monthly, weekly,
daily, and hourly).
• Getting the mill ready includes tasks like setting up rolls for roll changes,
preparing roll fittings, straightening rolls, and ensuring blade readiness.
Figure 3 Control, communication and monitoring of the Hille hot-rolling mill
2. Process Control Instruments:
• Pyrometers, ammeters (load indicators), dynamometers, and tachometers are
used to control and regulate the rolling process.
• Hourly rolling schedules and continuous testing of intermediate samples help
adjust pass sequences and roll changes.
3. Preparatory Operations:
• Preparing billets for rolling involves adhering to schedules (monthly, weekly,
daily, and hourly).
• Getting the mill ready includes tasks like setting up rolls for roll changes,
preparing roll fittings, straightening rolls, and ensuring blade readiness.
Figure 3 Control, communication and monitoring of the Hille hot-rolling mill
4
4. Equipment Maintenance and Repairs:
• Regular maintenance and repairs are essential for furnace installations and
auxiliary equipment.
• General overhauls (capital repairs) should be planned strategically, avoiding
lengthy shutdowns.
• Running repairs, preventive maintenance, and timely replacements contribute
to efficient operation.
5. Efficiency Engineering:
• Introducing efficiency systems optimizes resource allocation and minimizes
labor-intensive tasks.
• Multi-specialization of workers, elimination of duplicated functions, and
automation (including industrial closed-circuit television systems) enhance
productivity.
• Efficient production management involves job rating, wage accounting, and
streamlined processes.
6. Cost Management and Record Keeping:
• Accurate recording of expenditures on materials, fuel, power, water, and
replacement equipment is crucial.
• Tracking semi-finished products, waste, and finished goods helps calculate
actual rolling costs.
• Flow charts based on optimum process parameters guide routine production
conditions.
4. Equipment Maintenance and Repairs:
• Regular maintenance and repairs are essential for furnace installations and
auxiliary equipment.
• General overhauls (capital repairs) should be planned strategically, avoiding
lengthy shutdowns.
• Running repairs, preventive maintenance, and timely replacements contribute
to efficient operation.
5. Efficiency Engineering:
• Introducing efficiency systems optimizes resource allocation and minimizes
labor-intensive tasks.
• Multi-specialization of workers, elimination of duplicated functions, and
automation (including industrial closed-circuit television systems) enhance
productivity.
• Efficient production management involves job rating, wage accounting, and
streamlined processes.
6. Cost Management and Record Keeping:
• Accurate recording of expenditures on materials, fuel, power, water, and
replacement equipment is crucial.
• Tracking semi-finished products, waste, and finished goods helps calculate
actual rolling costs.
• Flow charts based on optimum process parameters guide routine production
conditions.
5
2 Technological Instruction on Preparation of Rolls
This set of guidelines is crucial for ensuring efficient and effective rolling
processes in such mills.
1. Preparation of Rolls:
• This step involves getting the rolls ready for
the rolling process. It includes inspecting
existing rolls, ordering new rolls as needed,
and maintaining a stock of rolls suitable for
different profiles.
• Worn-out rolls should be sent to the roll
turning shop for redressing, and a schedule
should be maintained to ensure timely
availability.
Figure 5 Roll Component
Figure 4 Worn-out Pass
2 Technological Instruction on Preparation of Rolls
This set of guidelines is crucial for ensuring efficient and effective rolling
processes in such mills.
1. Preparation of Rolls:
• This step involves getting the rolls ready for
the rolling process. It includes inspecting
existing rolls, ordering new rolls as needed,
and maintaining a stock of rolls suitable for
different profiles.
• Worn-out rolls should be sent to the roll
turning shop for redressing, and a schedule
should be maintained to ensure timely
availability.
Figure 5 Roll Component
Figure 4 Worn-out Pass
6
2. Roll Tackles and Other Accessories:
• Roll tackles, tilter inserts, guards, entry and exit boxes, and guides play
essential roles during rolling. Proper preparation of these components ensures
smooth operations.
• For each stand and profile, the necessary accessories should be in place.
Figure 6 Stand component
2. Roll Tackles and Other Accessories:
• Roll tackles, tilter inserts, guards, entry and exit boxes, and guides play
essential roles during rolling. Proper preparation of these components ensures
smooth operations.
• For each stand and profile, the necessary accessories should be in place.
Figure 6 Stand component
7
3. Cold Shears and Shear Blades:
• Cold shears are used for cutting profiles. Adequate preparation of shear blades
is essential.
• Old, broken, or chipped shear blades should be replaced promptly.
4. Roll Changing Program:
• Roll changing follows a specific program based on the rolling schedule.
• The responsible person (usually the In-charge of Operations) prepares the roll
changing program, considering the profile being rolled and optimizing roll
usage.
Figure 7 Broken and chipped shear blades
Figure 8 Rolling Sequence
3. Cold Shears and Shear Blades:
• Cold shears are used for cutting profiles. Adequate preparation of shear blades
is essential.
• Old, broken, or chipped shear blades should be replaced promptly.
4. Roll Changing Program:
• Roll changing follows a specific program based on the rolling schedule.
• The responsible person (usually the In-charge of Operations) prepares the roll
changing program, considering the profile being rolled and optimizing roll
usage.
Figure 7 Broken and chipped shear blades
Figure 8 Rolling Sequence
8
5. Collaboration with Mill Foreman:
• The rolling scheme and any modifications to improve results should be
communicated to the Mill Foreman in a timely manner.
• Effective coordination ensures smooth operations.
6. Roll Selection and Bearing Assembly:
• The In-charge of Operations selects the appropriate sets of rolls for rolling.
• These rolls are then sent to the bearing shop for assembly.
• Spare rolls are also kept on hand for emergencies.
Figure 9 Typical roll and bearing arrangement
5. Collaboration with Mill Foreman:
• The rolling scheme and any modifications to improve results should be
communicated to the Mill Foreman in a timely manner.
• Effective coordination ensures smooth operations.
6. Roll Selection and Bearing Assembly:
• The In-charge of Operations selects the appropriate sets of rolls for rolling.
• These rolls are then sent to the bearing shop for assembly.
• Spare rolls are also kept on hand for emergencies.
Figure 9 Typical roll and bearing arrangement
9
7. Furnace Preparation:
• Before starting the rolling process for a specific profile, the furnaces must be
filled with billets of the required quality and size.
• Shift Managers handle this task based on the In-charge’s instructions.
8. Finishing & Shipping Considerations:
• The In-charge of Finishing & Shipping focuses on straightening machine
rollers and shear blades.
• Maintaining an inventory of rollers and shear blades is crucial.
• Timely replacement and redressing ensure uninterrupted production.
9. Equipment Condition:
• Mechanical and electrical equipment (such as chain transfers, rope transfers,
and electrical components) must be in good condition.
• Regular inspections are necessary to prevent disruptions during rolling.
Figure 10 Reheating furnace
7. Furnace Preparation:
• Before starting the rolling process for a specific profile, the furnaces must be
filled with billets of the required quality and size.
• Shift Managers handle this task based on the In-charge’s instructions.
8. Finishing & Shipping Considerations:
• The In-charge of Finishing & Shipping focuses on straightening machine
rollers and shear blades.
• Maintaining an inventory of rollers and shear blades is crucial.
• Timely replacement and redressing ensure uninterrupted production.
9. Equipment Condition:
• Mechanical and electrical equipment (such as chain transfers, rope transfers,
and electrical components) must be in good condition.
• Regular inspections are necessary to prevent disruptions during rolling.
Figure 10 Reheating furnace
10
2.1 Planning and Preparation during breakdown
In case of roll breakage or urgent roll changing, the
command for roll assembling can be undertaken by
the Shift Manager of that particular shift, with the
consent of the in charge (operation). Before the start
of roll changing, passes of the assembled rolls should
checked carefully to see the condition of pass and
whether the correct pass is marked, especially in case
of finishing stands rolls for beams and channels. If the
pass is found defective. Foreman (operation) should
see that these passes are not used. He should inform
to the in charge (operation).
Furnace staff should be intimated, about the probable time the job of roll changing
will be taken for change over. Foreman (operation) should be made responsible for
carrying out this job with the consultation to Shift Manager.
Figure 12 pass breakage
Figure 11 Failure Mechanism
2.1 Planning and Preparation during breakdown
In case of roll breakage or urgent roll changing, the
command for roll assembling can be undertaken by
the Shift Manager of that particular shift, with the
consent of the in charge (operation). Before the start
of roll changing, passes of the assembled rolls should
checked carefully to see the condition of pass and
whether the correct pass is marked, especially in case
of finishing stands rolls for beams and channels. If the
pass is found defective. Foreman (operation) should
see that these passes are not used. He should inform
to the in charge (operation).
Furnace staff should be intimated, about the probable time the job of roll changing
will be taken for change over. Foreman (operation) should be made responsible for
carrying out this job with the consultation to Shift Manager.
Figure 12 pass breakage
Figure 11 Failure Mechanism
11
2.2 Pre-cautions to be Taken During Roll Changing
1. Informing Shift Foremen:
• The outgoing Shift Foreman (operation) should communicate the roll
changing program to the Shift Foreman (Mech.) in advance.
• Assembled rolls should be kept ready on the mill floor for the next shift.
2. Roll Preparation:
• The Shift Foreman (Mech.) must ensure that rolls are fitted with spindle heads
and lubrication fittings.
• During spindle head fitting, check the keyway on the rolls and inspect slide
blocks. Replace worn-out slide blocks and avoid using loose spindle heads.
3. Hydraulic Wedges:
• Before shifting the stand, ensure that all hydraulic wedges are fully decamped.
• Proper decamping prevents issues during movement.
4. Coupling Engagement:
• Carefully engage and disengage the coupling. Avoid extreme movements that
could damage lubrication pipelines or jam the spindle shaft.
• Smooth coupling operation is essential.
5. Bottom Screw-Down Mechanism:
• Before starting roll changing, operate the bottom screw-down mechanism in
both directions to verify its proper functioning.
• This mechanism controls roll positioning.
6. Displacement Mechanism Check:
• After decamping the stand and pinion stand, check the displacement
mechanism in both directions.
• Ensure it works smoothly to avoid disruptions during roll changing.
2.2 Pre-cautions to be Taken During Roll Changing
1. Informing Shift Foremen:
• The outgoing Shift Foreman (operation) should communicate the roll
changing program to the Shift Foreman (Mech.) in advance.
• Assembled rolls should be kept ready on the mill floor for the next shift.
2. Roll Preparation:
• The Shift Foreman (Mech.) must ensure that rolls are fitted with spindle heads
and lubrication fittings.
• During spindle head fitting, check the keyway on the rolls and inspect slide
blocks. Replace worn-out slide blocks and avoid using loose spindle heads.
3. Hydraulic Wedges:
• Before shifting the stand, ensure that all hydraulic wedges are fully decamped.
• Proper decamping prevents issues during movement.
4. Coupling Engagement:
• Carefully engage and disengage the coupling. Avoid extreme movements that
could damage lubrication pipelines or jam the spindle shaft.
• Smooth coupling operation is essential.
5. Bottom Screw-Down Mechanism:
• Before starting roll changing, operate the bottom screw-down mechanism in
both directions to verify its proper functioning.
• This mechanism controls roll positioning.
6. Displacement Mechanism Check:
• After decamping the stand and pinion stand, check the displacement
mechanism in both directions.
• Ensure it works smoothly to avoid disruptions during roll changing.
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7. Ratchet Handle Position:
• After leveling the bottom roll, keep the ratchet handle vertical using locking
arrangements.
• Avoid leaving it resting on the sides, as it could get stuck or bend during stand
displacement.
8. Base Channel Cleaning:
• Thoroughly clean the stand base channel with water when the stand is
disengaged.
• Accumulated scale can obstruct the movement of wedge bolts, affecting the
displacement mechanism.
9. Greasing Slide Blocks:
• Apply grease thoroughly to the slide blocks while engaging the stand.
• Proper lubrication ensures smooth movement.
10. Top Roll Placement:
• When putting the top roll in the stand, ensure there is a gap between the top
and bottom rolls before pressing.
• Avoid excessive pressure on the top roll during placement.
11. Spring Compression:
• While pressing the top roll, ensure that the spring is not fully compressed.
• Over-compression could lead to spring breakage within the housing.
12. Spindle Inclination:
• Both spindles should have equal and opposite inclinations.
• Proper alignment ensures uniform rolling forces.
7. Ratchet Handle Position:
• After leveling the bottom roll, keep the ratchet handle vertical using locking
arrangements.
• Avoid leaving it resting on the sides, as it could get stuck or bend during stand
displacement.
8. Base Channel Cleaning:
• Thoroughly clean the stand base channel with water when the stand is
disengaged.
• Accumulated scale can obstruct the movement of wedge bolts, affecting the
displacement mechanism.
9. Greasing Slide Blocks:
• Apply grease thoroughly to the slide blocks while engaging the stand.
• Proper lubrication ensures smooth movement.
10. Top Roll Placement:
• When putting the top roll in the stand, ensure there is a gap between the top
and bottom rolls before pressing.
• Avoid excessive pressure on the top roll during placement.
11. Spring Compression:
• While pressing the top roll, ensure that the spring is not fully compressed.
• Over-compression could lead to spring breakage within the housing.
12. Spindle Inclination:
• Both spindles should have equal and opposite inclinations.
• Proper alignment ensures uniform rolling forces.
13
2.3 Points/areas to be Checked after Roll Changing
a) Mechanical:
1. Side Coupling Guards:
• Verify that all side coupling guards are correctly positioned.
• These guards prevent accidental contact with rotating parts and enhance
safety.
2. Avoid Interference with Rotating Parts:
• Ensure that tools like crowbars and side guards do not touch any rotating
components.
• Accidental interference can lead to damage or safety hazards.
3. Proper Clamping of Stands:
• Before allowing the main drive to rotate, ensure that all stands are securely
clamped.
• Proper clamping prevents misalignment and instability during rolling.
Figure 13 Roll Stand
2.3 Points/areas to be Checked after Roll Changing
a) Mechanical:
1. Side Coupling Guards:
• Verify that all side coupling guards are correctly positioned.
• These guards prevent accidental contact with rotating parts and enhance
safety.
2. Avoid Interference with Rotating Parts:
• Ensure that tools like crowbars and side guards do not touch any rotating
components.
• Accidental interference can lead to damage or safety hazards.
3. Proper Clamping of Stands:
• Before allowing the main drive to rotate, ensure that all stands are securely
clamped.
• Proper clamping prevents misalignment and instability during rolling.
Figure 13 Roll Stand
14
4. Oil Film Bearing Pipes:
• Thoroughly check the inlet and outlet pipes for oil film bearings.
• Proper lubrication is crucial for bearing performance and longevity.
5. Oil Flow Inspection:
• Verify the oil flow to critical components, including the reducer, pinion stand,
and main bearings.
• Inadequate lubrication can lead to premature wear and equipment failure.
6. Floor Plates Alignment:
• Ensure that all floor plates are correctly positioned.
• Misaligned plates can affect the stability of the rolling mill.
7. Cooling Arrangement for Tilter:
• If a tilter is used to tilt workpieces by 90° between horizontal stands, ensure
an adequate cooling arrangement.
• Proper cooling prevents overheating during tilting operations.
8. Post-Rotation Checks:
After the main drives start rotating, periodically check the following:
• Bearing Temperature: Monitor bearing temperatures to prevent
overheating.
• Spindle Heads: Check if spindle heads are getting excessively heated.
• Vibration: Inspect stands and other equipment for abnormal vibrations.
• Oil Flow: Confirm that oil flows properly to all critical components.
4. Oil Film Bearing Pipes:
• Thoroughly check the inlet and outlet pipes for oil film bearings.
• Proper lubrication is crucial for bearing performance and longevity.
5. Oil Flow Inspection:
• Verify the oil flow to critical components, including the reducer, pinion stand,
and main bearings.
• Inadequate lubrication can lead to premature wear and equipment failure.
6. Floor Plates Alignment:
• Ensure that all floor plates are correctly positioned.
• Misaligned plates can affect the stability of the rolling mill.
7. Cooling Arrangement for Tilter:
• If a tilter is used to tilt workpieces by 90° between horizontal stands, ensure
an adequate cooling arrangement.
• Proper cooling prevents overheating during tilting operations.
8. Post-Rotation Checks:
After the main drives start rotating, periodically check the following:
• Bearing Temperature: Monitor bearing temperatures to prevent
overheating.
• Spindle Heads: Check if spindle heads are getting excessively heated.
• Vibration: Inspect stands and other equipment for abnormal vibrations.
• Oil Flow: Confirm that oil flows properly to all critical components.
15
9. Overall Equipment Inspection:
• Thoroughly inspect all equipment to ensure proper functioning.
• Address any issues promptly to avoid disruptions during production.
10. Speed Points Preparation:
• Prepare and verify speed points specific to different product profiles.
• Proper speed settings are essential for achieving desired product dimensions.
11. Mechanism and Fitting Checks:
• Any mechanisms or fittings that were changed or repaired during roll
changing should be thoroughly checked during trial runs.
• Ensure they perform as expected to maintain smooth operations.
9. Overall Equipment Inspection:
• Thoroughly inspect all equipment to ensure proper functioning.
• Address any issues promptly to avoid disruptions during production.
10. Speed Points Preparation:
• Prepare and verify speed points specific to different product profiles.
• Proper speed settings are essential for achieving desired product dimensions.
11. Mechanism and Fitting Checks:
• Any mechanisms or fittings that were changed or repaired during roll
changing should be thoroughly checked during trial runs.
• Ensure they perform as expected to maintain smooth operations.
16
b) Electrical:
1. Screw Down Mechanism Connections:
• During roll changing, inspect the connections and plugs of the screw-down
mechanism.
• Any defects or issues should be promptly rectified to ensure proper
functioning.
2. Trailing Cable for Vertical Stand Housing:
• When moving the vertical stand housing in or out, pay attention to the trailing
cable.
• Ensure it doesn’t get stuck or subjected to tension or pressure, which could
lead to damage.
3. Photocell and Tilter Testing:
• Clean the photocell (used for automation) and test the auto tilters.
• Proper functioning of these components is essential for safety and precision.
4. Main Motor Temperature Checks:
• When starting the mill, monitor the temperature of the main motors.
• Regular checks (3 to 4 times per shift) help detect any anomalies.
5. Ventilation System for Motors:
• Motors equipped with ventilation systems should be inspected.
• Ensure they are operational and maintain proper cooling.
6. Bearing Temperature Monitoring:
• Check the temperature of bearings in the main drives and main M.G. (motor-
generator) sets.
• Frequent monitoring (hourly during the running shift) helps prevent
overheating.
b) Electrical:
1. Screw Down Mechanism Connections:
• During roll changing, inspect the connections and plugs of the screw-down
mechanism.
• Any defects or issues should be promptly rectified to ensure proper
functioning.
2. Trailing Cable for Vertical Stand Housing:
• When moving the vertical stand housing in or out, pay attention to the trailing
cable.
• Ensure it doesn’t get stuck or subjected to tension or pressure, which could
lead to damage.
3. Photocell and Tilter Testing:
• Clean the photocell (used for automation) and test the auto tilters.
• Proper functioning of these components is essential for safety and precision.
4. Main Motor Temperature Checks:
• When starting the mill, monitor the temperature of the main motors.
• Regular checks (3 to 4 times per shift) help detect any anomalies.
5. Ventilation System for Motors:
• Motors equipped with ventilation systems should be inspected.
• Ensure they are operational and maintain proper cooling.
6. Bearing Temperature Monitoring:
• Check the temperature of bearings in the main drives and main M.G. (motor-
generator) sets.
• Frequent monitoring (hourly during the running shift) helps prevent
overheating.
17
7. Leakage from Hose Pipes and Connections:
• Inspect all main hose pipes and connections for leaks.
• Address any leaks promptly to prevent fluid loss or equipment damage.
8. Main Drive Loads:
• Regularly check the loads on all main drives (such as motors, gearboxes, etc.).
• Proper load distribution ensures efficient operation.
9. Commutator Sparking:
• Examine the commutator (part of direct current motors) for sparking.
• Sparking can indicate wear or other issues.
10. Equipment Panels and Relay Contactors:
• Inspect major mill equipment panels that operate using relay contactors.
• Ensure proper functioning and address any issues promptly.
11. Cooling Bed Roll Table Motors:
• Regularly check and rectify any problems with cooling bed roll table motors.
• These motors play a crucial role in material handling after rolling.
12. Survey of Roll Table Motors and Auxiliary Fixing:
• Conduct surveys of roll table motors and assess auxiliary components.
• Proper fixing and alignment are essential for smooth material flow.
13. Overall Equipment Inspection:
• Thoroughly check all electrical equipment to ensure proper working.
• Address any issues promptly to avoid disruptions during production.
14. Special Points for Different Profiles:
• Prepare and verify specific settings (speeds, positions, etc.) required for
different product profiles.
• Customization ensures accurate rolling results.
7. Leakage from Hose Pipes and Connections:
• Inspect all main hose pipes and connections for leaks.
• Address any leaks promptly to prevent fluid loss or equipment damage.
8. Main Drive Loads:
• Regularly check the loads on all main drives (such as motors, gearboxes, etc.).
• Proper load distribution ensures efficient operation.
9. Commutator Sparking:
• Examine the commutator (part of direct current motors) for sparking.
• Sparking can indicate wear or other issues.
10. Equipment Panels and Relay Contactors:
• Inspect major mill equipment panels that operate using relay contactors.
• Ensure proper functioning and address any issues promptly.
11. Cooling Bed Roll Table Motors:
• Regularly check and rectify any problems with cooling bed roll table motors.
• These motors play a crucial role in material handling after rolling.
12. Survey of Roll Table Motors and Auxiliary Fixing:
• Conduct surveys of roll table motors and assess auxiliary components.
• Proper fixing and alignment are essential for smooth material flow.
13. Overall Equipment Inspection:
• Thoroughly check all electrical equipment to ensure proper working.
• Address any issues promptly to avoid disruptions during production.
14. Special Points for Different Profiles:
• Prepare and verify specific settings (speeds, positions, etc.) required for
different product profiles.
• Customization ensures accurate rolling results.
18
2.4 Starting the Mill After Major Roll Changing
General rules for mill adjustment after roll changing are as follows:
a) Before the start of mill:
1. Rolling Scheme Confirmation:
• Before starting the mill, verify that the rolling scheme (sequence of passes)
aligns with the roll pass design.
• The In-charge of Operations should confirm this alignment.
2. Pass Correspondence:
• Ensure that the passes in all stands match the roll pass design.
• Any deviation from the design should only occur with explicit permission
from the In-charge of Operations.
Figure 14 Example of rolling schedule
Figure 15 Roll pass design
2.4 Starting the Mill After Major Roll Changing
General rules for mill adjustment after roll changing are as follows:
a) Before the start of mill:
1. Rolling Scheme Confirmation:
• Before starting the mill, verify that the rolling scheme (sequence of passes)
aligns with the roll pass design.
• The In-charge of Operations should confirm this alignment.
2. Pass Correspondence:
• Ensure that the passes in all stands match the roll pass design.
• Any deviation from the design should only occur with explicit permission
from the In-charge of Operations.
Figure 14 Example of rolling schedule
Figure 15 Roll pass design
19
3. Rolling Tackles and Modifications:
• Confirm that the rolling tackles (entry and exit sides of rolls) are as specified
by the In-charge of Operations.
• Avoid using modified rolling tackles without consulting the In-charge.
4. Twisting Removal:
• During mill adjustments, eliminate any twisting of the metal around its axis.
• Twisting can lead to product defects and affect the final shape.
5. Bending Elimination:
• Ensure that pieces do not bend sideways, up, or down during rolling.
• Proper alignment prevents shape distortions.
6. Section Distortion Removal:
• Check for any distortion in the section (profile) during adjustments.
• Adjust stands to eliminate distortions and maintain accurate dimensions.
7. Defect-Free Finished Products:
• The ultimate goal is to produce finished products free from rolling defects.
• Inspect the quality of the rolled sections to ensure defect-free results.
8. Final Speed Adjustments:
• Only after completing all the above steps should the final speed adjustments
be made.
• Once everything is aligned and adjusted, the mill is considered ready for
operation.
3. Rolling Tackles and Modifications:
• Confirm that the rolling tackles (entry and exit sides of rolls) are as specified
by the In-charge of Operations.
• Avoid using modified rolling tackles without consulting the In-charge.
4. Twisting Removal:
• During mill adjustments, eliminate any twisting of the metal around its axis.
• Twisting can lead to product defects and affect the final shape.
5. Bending Elimination:
• Ensure that pieces do not bend sideways, up, or down during rolling.
• Proper alignment prevents shape distortions.
6. Section Distortion Removal:
• Check for any distortion in the section (profile) during adjustments.
• Adjust stands to eliminate distortions and maintain accurate dimensions.
7. Defect-Free Finished Products:
• The ultimate goal is to produce finished products free from rolling defects.
• Inspect the quality of the rolled sections to ensure defect-free results.
8. Final Speed Adjustments:
• Only after completing all the above steps should the final speed adjustments
be made.
• Once everything is aligned and adjusted, the mill is considered ready for
operation.
20
b) After the start of mill
1. Mill Adjustment by Foreman (Operation):
• After major roll changing, the Foreman (Operation) is responsible for
adjusting the mill.
• This adjustment ensures that the mill is ready for production.
2. Reduction Scheme and Rolling Tackle Adjustments:
• During mill adjustment, changes in the reduction scheme (pass sequence) and
adjustments to rolling tackles can be made.
• Any modifications within the tolerance of the finished product may be done
with permission from the Foreman (Operation).
3. Authorized Personnel for Mill Start:
• Only the Shift Foreman (Operation) is allowed to start the mill or individual
stands.
• Unauthorized personnel should not enter the mill area during adjustments.
4. Billet Pushing and Furnace Preparation:
• The Shift Foreman (Operation) signals the pushing of billets from the
furnaces.
• Only one billet at a time is pushed out for mill adjustment.
• Return billets without heat numbers are used for this purpose.
5. Sample Pieces for Pass Burning:
• Sample pieces are heated in the furnaces and taken out during pass burning.
• The selection of these sample pieces is done by the Foreman (Operation).
b) After the start of mill
1. Mill Adjustment by Foreman (Operation):
• After major roll changing, the Foreman (Operation) is responsible for
adjusting the mill.
• This adjustment ensures that the mill is ready for production.
2. Reduction Scheme and Rolling Tackle Adjustments:
• During mill adjustment, changes in the reduction scheme (pass sequence) and
adjustments to rolling tackles can be made.
• Any modifications within the tolerance of the finished product may be done
with permission from the Foreman (Operation).
3. Authorized Personnel for Mill Start:
• Only the Shift Foreman (Operation) is allowed to start the mill or individual
stands.
• Unauthorized personnel should not enter the mill area during adjustments.
4. Billet Pushing and Furnace Preparation:
• The Shift Foreman (Operation) signals the pushing of billets from the
furnaces.
• Only one billet at a time is pushed out for mill adjustment.
• Return billets without heat numbers are used for this purpose.
5. Sample Pieces for Pass Burning:
• Sample pieces are heated in the furnaces and taken out during pass burning.
• The selection of these sample pieces is done by the Foreman (Operation).
21
6. Dimension Checking and Load Inspection:
• The Foreman (Operation) checks the dimensions of pieces after roughing,
intermediate, and finishing groups.
• Loads on different stands are also verified for all sections.
• Corrections during mill adjustment are done consecutively based on the
rolling order.
7. Roller Observations During Rolling:
• When the bar passes through pre-finishing and finishing stands, the roller
should pay attention to the following:
− Proper gripping of metal by rolls.
− Direction of twist in the bar.
− Nature of bending in the bar.
− Overfilling and underfilling of passes.
• The roller corrects any inaccuracies and takes samples to examine dimensions.
• Necessary adjustments are made to achieve the correct bar dimensions.
8. Foreman Approval for Normal Rolling:
• The Foreman should review the profile and satisfy themselves that everything
is in order.
• Once satisfied, they give permission to start normal rolling.
9. Sample Collection from Saw:
• Samples are collected from the sample saw with permission from the Foreman
or roller.
• These samples are used for quality control and verification.
6. Dimension Checking and Load Inspection:
• The Foreman (Operation) checks the dimensions of pieces after roughing,
intermediate, and finishing groups.
• Loads on different stands are also verified for all sections.
• Corrections during mill adjustment are done consecutively based on the
rolling order.
7. Roller Observations During Rolling:
• When the bar passes through pre-finishing and finishing stands, the roller
should pay attention to the following:
− Proper gripping of metal by rolls.
− Direction of twist in the bar.
− Nature of bending in the bar.
− Overfilling and underfilling of passes.
• The roller corrects any inaccuracies and takes samples to examine dimensions.
• Necessary adjustments are made to achieve the correct bar dimensions.
8. Foreman Approval for Normal Rolling:
• The Foreman should review the profile and satisfy themselves that everything
is in order.
• Once satisfied, they give permission to start normal rolling.
9. Sample Collection from Saw:
• Samples are collected from the sample saw with permission from the Foreman
or roller.
• These samples are used for quality control and verification.
22
2.5 Examination of the Finished Products
These are general rules for taking samples and examination of metal on the cooling
beds.
1. Double Check of Finished Products:
Before starting normal rolling, it’s crucial to double-check the finished product.
This involves:
• Examining technological samples at the sample saw.
• Checking dimensions of finished products directly on the cooling bed.
• Ensuring there are no observable defects.
2. Handling Defective Bars:
• Bars with defects rolled during mill setting should be separated from the good
metal.
• The recorder of the cooling beds, following the roller’s instructions, carries
out this separation.
3. Roller Examination of Bars:
• The roller examines the bar from which the sample is taken.
• Dimensions are checked at different distances from the back end of the bar.
4. Sample Inspection from the Saw:
Samples taken from the saw serve two purposes:
• Checking dimensions against desired tolerances specified by standards.
• Examining the surface quality of the product.
2.5 Examination of the Finished Products
These are general rules for taking samples and examination of metal on the cooling
beds.
1. Double Check of Finished Products:
Before starting normal rolling, it’s crucial to double-check the finished product.
This involves:
• Examining technological samples at the sample saw.
• Checking dimensions of finished products directly on the cooling bed.
• Ensuring there are no observable defects.
2. Handling Defective Bars:
• Bars with defects rolled during mill setting should be separated from the good
metal.
• The recorder of the cooling beds, following the roller’s instructions, carries
out this separation.
3. Roller Examination of Bars:
• The roller examines the bar from which the sample is taken.
• Dimensions are checked at different distances from the back end of the bar.
4. Sample Inspection from the Saw:
Samples taken from the saw serve two purposes:
• Checking dimensions against desired tolerances specified by standards.
• Examining the surface quality of the product.
23
5. Immediate Action for Rolling Defects:
• If any rolling defect is detected (such as roughness, scabs, or sticking bars),
rolling should be promptly stopped.
• Necessary actions are taken to rectify the defect.
6. Attention to Cooling Bed Inspection:
When examining bars on the cooling bed:
• Pay special attention to defects.
• Periodicity of defects (e.g., roughness) on any side of the section indicates a
problem in one of the stands.
• Stop rolling to address such defects.
7. Sampling During Steady Rolling:
• After every 100 to 200 pieces during steady rolling, take samples at the hot
saw.
• The last sample from the running shift remains on the control table for the
next shift.
8. Straightening Machine Approach Roll Table Examination:
• The roller should periodically examine the pieces on the straightening
machine approach roll table while rolling is ongoing.
• This ensures continuous quality control.
5. Immediate Action for Rolling Defects:
• If any rolling defect is detected (such as roughness, scabs, or sticking bars),
rolling should be promptly stopped.
• Necessary actions are taken to rectify the defect.
6. Attention to Cooling Bed Inspection:
When examining bars on the cooling bed:
• Pay special attention to defects.
• Periodicity of defects (e.g., roughness) on any side of the section indicates a
problem in one of the stands.
• Stop rolling to address such defects.
7. Sampling During Steady Rolling:
• After every 100 to 200 pieces during steady rolling, take samples at the hot
saw.
• The last sample from the running shift remains on the control table for the
next shift.
8. Straightening Machine Approach Roll Table Examination:
• The roller should periodically examine the pieces on the straightening
machine approach roll table while rolling is ongoing.
• This ensures continuous quality control.
24
2.5.1 Finished Product Defectives
Problem:
Ovality in the finished TMT product.
Reasons:
The sides of pass are not completely filled up. This is due to less metal from
previous stand when height of metal is correct. If the height is more than the top roll
of finishing stand should be pressed.
Rectification:
Metal from previous stand should be increased if metal height is connected.
If, there is one side fin and at other side oval, then entry box of finishing stand should
be shifted towards the oval side.
Figure 16 Ovality in round finished product.
2.5.1 Finished Product Defectives
Problem:
Ovality in the finished TMT product.
Reasons:
The sides of pass are not completely filled up. This is due to less metal from
previous stand when height of metal is correct. If the height is more than the top roll
of finishing stand should be pressed.
Rectification:
Metal from previous stand should be increased if metal height is connected.
If, there is one side fin and at other side oval, then entry box of finishing stand should
be shifted towards the oval side.
Figure 16 Ovality in round finished product.
25
Problem:
Diagonal Difference in the finished product.
Reasons:
Right or left diagonal may be more than the allowable tolerance. Reasons for
this cause are the improper setting of the entry guide or rolls.
Rectification:
The guide is to be shifted against the opposite direction of the higher shoulder,
if it is not adjusted by the shifting of guide, then rolls may be adjusted.
Problem:
Fins on any one side and on the other side.
Figure 17 Diagonal Difference
Figure 18 Fin shape on round.
Problem:
Diagonal Difference in the finished product.
Reasons:
Right or left diagonal may be more than the allowable tolerance. Reasons for
this cause are the improper setting of the entry guide or rolls.
Rectification:
The guide is to be shifted against the opposite direction of the higher shoulder,
if it is not adjusted by the shifting of guide, then rolls may be adjusted.
Problem:
Fins on any one side and on the other side.
Figure 17 Diagonal Difference
Figure 18 Fin shape on round.
26
Rectification:
• One sided fin indicates the defective fixing of entry box of the finishing stand,
which should be shifted opposite to the defect.
• Both side fins may be due to excess metal from the pre-finishing oval pass. The
thickness of oval pass is to be reduced and if the oval pass is worn out, then, it
should be changed immediately.
• If fins are only at the end of bar, then tension should be removed in continuous
group of stands, especially finishing group of the mill.
• If false fins are noticed at the top and bottom of round, then this may be result of
oval with fin which wears out the finishing stand pass at top and bottom.
Problem:
Under-Filled in the finished product.
Figure 19 Under-Filled in the finished product.
Rectification:
• One sided fin indicates the defective fixing of entry box of the finishing stand,
which should be shifted opposite to the defect.
• Both side fins may be due to excess metal from the pre-finishing oval pass. The
thickness of oval pass is to be reduced and if the oval pass is worn out, then, it
should be changed immediately.
• If fins are only at the end of bar, then tension should be removed in continuous
group of stands, especially finishing group of the mill.
• If false fins are noticed at the top and bottom of round, then this may be result of
oval with fin which wears out the finishing stand pass at top and bottom.
Problem:
Under-Filled in the finished product.
Figure 19 Under-Filled in the finished product.
27
Rectification:
• Insufficient stock in the oval pass.
• Check the tension and if any, then remove it.
• Top/bottom dimension too large, which can be rectified by checking the top and
bottom dimensions of finished round and if it is too large then change of pass is
recommended.
Problem:
Fish-tail defect typically occurs at the end of a rolled bar.
Reasons:
• Improper Entry Roller Box Setting: If the entry roller box of the finishing stand
is not correctly adjusted, it can lead to uneven deformation and contribute to the
fish-tail defect.
• Jamming of Rollers in the Entry Box: If the rollers in the entry box become
jammed or misaligned, it affects the material flow and can result in irregular
shapes at the bar’s end.
Figure 20 Fish-tail defect.
Rectification:
• Insufficient stock in the oval pass.
• Check the tension and if any, then remove it.
• Top/bottom dimension too large, which can be rectified by checking the top and
bottom dimensions of finished round and if it is too large then change of pass is
recommended.
Problem:
Fish-tail defect typically occurs at the end of a rolled bar.
Reasons:
• Improper Entry Roller Box Setting: If the entry roller box of the finishing stand
is not correctly adjusted, it can lead to uneven deformation and contribute to the
fish-tail defect.
• Jamming of Rollers in the Entry Box: If the rollers in the entry box become
jammed or misaligned, it affects the material flow and can result in irregular
shapes at the bar’s end.
Figure 20 Fish-tail defect.
28
Rectification:
• Check and Adjust Entry Roller Box:
− Regularly inspect and adjust the entry roller box to ensure proper alignment
and smooth material entry.
− Ensure that the entry guides are correctly positioned to guide the bar
effectively.
• Monitor Rollers and Guides:
− Keep the rollers in good condition and free from any obstructions.
− Lubricate and maintain the guides to prevent jamming.
• Optimize Cooling Process:
− Proper cooling is essential to prevent defects. Ensure uniform cooling across
the bar’s cross-section.
− Address any cooling-related issues that may contribute to irregular shapes.
Problem:
Worn out Mark on the finale product.
Figure 21 Worn out marks.
Rectification:
• Check and Adjust Entry Roller Box:
− Regularly inspect and adjust the entry roller box to ensure proper alignment
and smooth material entry.
− Ensure that the entry guides are correctly positioned to guide the bar
effectively.
• Monitor Rollers and Guides:
− Keep the rollers in good condition and free from any obstructions.
− Lubricate and maintain the guides to prevent jamming.
• Optimize Cooling Process:
− Proper cooling is essential to prevent defects. Ensure uniform cooling across
the bar’s cross-section.
− Address any cooling-related issues that may contribute to irregular shapes.
Problem:
Worn out Mark on the finale product.
Figure 21 Worn out marks.
29
Reasons:
Worn out marks indicate that the diagonals of the bar are more than the height
and width of the pass.
Rectification:
The recommended action is to immediately change the pass to address this
issue.
Problem:
Dimensions of the finished product is less than desired.
Reasons:
Minor axis oval entering the round finishing pass is less in dimension.
Rectification:
• Increase the dimension of the minor axis of the oval from the leading groove.
• If this action fails, increase dimension of square groove preceding the oval
groove.
Figure 22 Dimensions of the finishing pass.
Reasons:
Worn out marks indicate that the diagonals of the bar are more than the height
and width of the pass.
Rectification:
The recommended action is to immediately change the pass to address this
issue.
Problem:
Dimensions of the finished product is less than desired.
Reasons:
Minor axis oval entering the round finishing pass is less in dimension.
Rectification:
• Increase the dimension of the minor axis of the oval from the leading groove.
• If this action fails, increase dimension of square groove preceding the oval
groove.
Figure 22 Dimensions of the finishing pass.
30
Problem:
Rolled weight in Kg/meter is either more or less than the standard.
Reasons:
Cross sectional area of round rolled is either more or less.
Rectification:
In case the round rolled is on lighter side, reduce the drafting (close the gap)
in the finishing pass. If on the heavier side, increase the draft (open the gap) in the
finishing groove.
The following formula used to calculate the nominal weight of the bar:
??????��??????��� ??????�??????�ℎ�=
????????????������
2
162.163
??????����� �� ??????��� ??????� ??????���� (�)=
??????���� ??????�??????�ℎ�
??????�� ??????�??????�ℎ�
Example:
??????��??????��� ??????�??????�ℎ� ��� ������� ??????????????????� 16 �� =
16
2
162.163
=1.579 ��/�
??????����� �� ??????��� ??????� ??????���� (�)=
2×10
3
1.579×12
= 106 ���
Problem:
Rolled weight in Kg/meter is either more or less than the standard.
Reasons:
Cross sectional area of round rolled is either more or less.
Rectification:
In case the round rolled is on lighter side, reduce the drafting (close the gap)
in the finishing pass. If on the heavier side, increase the draft (open the gap) in the
finishing groove.
The following formula used to calculate the nominal weight of the bar:
??????��??????��� ??????�??????�ℎ�=
????????????������
2
162.163
??????����� �� ??????��� ??????� ??????���� (�)=
??????���� ??????�??????�ℎ�
??????�� ??????�??????�ℎ�
Example:
??????��??????��� ??????�??????�ℎ� ��� ������� ??????????????????� 16 �� =
16
2
162.163
=1.579 ��/�
??????����� �� ??????��� ??????� ??????���� (�)=
2×10
3
1.579×12
= 106 ���
31
2.6 Net Yield of The Rolling Mill
The following general formula may be used for determining the actual hourly
output of a rolling mill:
�=��
3600 �
�
Where:
− P: net yield of the mill (t/h).
− Q: mass of billet or ingot.
− q: net yield factor.
− t: rolling rhythm.
− k: rolling mill use factor.
The rolling rhythm is determined in a number of ways, depending on the rolling mill
arrangement and rolling scheme. For a single stand blooming mill this is the total
time of rolling in the stand, including intervals between passing and successive
ingots. For multi stand rolling mills this is the time of passing in the finished stand,
including intervals between successive billets.
In general terms the rolling rhythm for a stand in which several passing are
performed is determined from the formula:
�= �
??????+�
??????
Where:
tp: rolling time for several passing or total productive time.
ti: time of intervals between passing.
2.6 Net Yield of The Rolling Mill
The following general formula may be used for determining the actual hourly
output of a rolling mill:
�=��
3600 �
�
Where:
− P: net yield of the mill (t/h).
− Q: mass of billet or ingot.
− q: net yield factor.
− t: rolling rhythm.
− k: rolling mill use factor.
The rolling rhythm is determined in a number of ways, depending on the rolling mill
arrangement and rolling scheme. For a single stand blooming mill this is the total
time of rolling in the stand, including intervals between passing and successive
ingots. For multi stand rolling mills this is the time of passing in the finished stand,
including intervals between successive billets.
In general terms the rolling rhythm for a stand in which several passing are
performed is determined from the formula:
�= �
??????+�
??????
Where:
tp: rolling time for several passing or total productive time.
ti: time of intervals between passing.
32
If rolling speed v is constant (disregarding speed gain) and the length of the work
piece after passing is L, then the productive time is determined from the formula:
�
??????=
�
�
3 Safety Management of Rolling Mill
Potential hazards from rolling come from heat radiation, high travel speeds of
the worked metal, concentration of moving and rotating mechanisms in the operating
area. It is also due to scattering of scales and shavings during shearing, sawing and
conditioning the metal.
Ensuring a safe working environment in rolling mill shops is essential due to the
inherent hazards associated with metalworking processes. Here are key safety
measures and practices:
1. Protective Garments and Individual Protection:
• Workers should wear appropriate protective gear, including goggles, helmets,
gloves, and specialized shoes.
• Asbestos cover plates may be necessary for specific tasks.
2. Guarding Moving and Rotating Mechanisms:
• Install shrouds to protect workers from moving and rotating parts.
• Wire guards on finishing and high-speed stands prevent accidental contact.
3. Tag System for Safe Access:
• Implement a tag system for safe access to mechanisms and stands.
• Electricians receive a tag confirming that the electrical circuit is
disconnected before maintenance or adjustments.
If rolling speed v is constant (disregarding speed gain) and the length of the work
piece after passing is L, then the productive time is determined from the formula:
�
??????=
�
�
3 Safety Management of Rolling Mill
Potential hazards from rolling come from heat radiation, high travel speeds of
the worked metal, concentration of moving and rotating mechanisms in the operating
area. It is also due to scattering of scales and shavings during shearing, sawing and
conditioning the metal.
Ensuring a safe working environment in rolling mill shops is essential due to the
inherent hazards associated with metalworking processes. Here are key safety
measures and practices:
1. Protective Garments and Individual Protection:
• Workers should wear appropriate protective gear, including goggles, helmets,
gloves, and specialized shoes.
• Asbestos cover plates may be necessary for specific tasks.
2. Guarding Moving and Rotating Mechanisms:
• Install shrouds to protect workers from moving and rotating parts.
• Wire guards on finishing and high-speed stands prevent accidental contact.
3. Tag System for Safe Access:
• Implement a tag system for safe access to mechanisms and stands.
• Electricians receive a tag confirming that the electrical circuit is
disconnected before maintenance or adjustments.
33
4. Interlocks and Signaling Devices:
• Use interlocks and signaling devices to prevent unsafe conditions.
• Mechanical shutters add redundancy to safety arrangements.
5. Tandem Rolling Mill Operator Protection:
• Install safety devices (such as guard posts and deflectors) to protect operators
working with tandem rolling mills.
• Clear, well-defined passages should be established within the mill area.
6. Overhead Bridges and Tunnels:
• Create safe passages using overhead bridges with railings or tunnels.
• These allow workers to move without interfering with rolling operations.
7. Good Lighting and Proper Metal Stacking:
• Adequate lighting ensures visibility and reduces accidents.
• Proper stacking prevents metal pieces from falling or shifting unexpectedly.
8. Timely Removal of Rejects:
• Promptly remove defective or rejected pieces from the rolling process.
• Accumulated rejects can create hazards and affect product quality.
4. Interlocks and Signaling Devices:
• Use interlocks and signaling devices to prevent unsafe conditions.
• Mechanical shutters add redundancy to safety arrangements.
5. Tandem Rolling Mill Operator Protection:
• Install safety devices (such as guard posts and deflectors) to protect operators
working with tandem rolling mills.
• Clear, well-defined passages should be established within the mill area.
6. Overhead Bridges and Tunnels:
• Create safe passages using overhead bridges with railings or tunnels.
• These allow workers to move without interfering with rolling operations.
7. Good Lighting and Proper Metal Stacking:
• Adequate lighting ensures visibility and reduces accidents.
• Proper stacking prevents metal pieces from falling or shifting unexpectedly.
8. Timely Removal of Rejects:
• Promptly remove defective or rejected pieces from the rolling process.
• Accumulated rejects can create hazards and affect product quality.
34
References
Gupta. (2021). Steel Rolling Principle, Process & Application. Abingdon: CRC
Press.
References
Gupta. (2021). Steel Rolling Principle, Process & Application. Abingdon: CRC
Press.
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