Carta Engl

CARTA® TeChnologY sYsTemCARTA® TeChnologY sYsTemGreater intelligence in seamless tube mills

Carta® combines three major advantages for the

owners of seamless tube mills: A significant increase

in yield, improved tube quality and optimised mill

utilisation. The Computer Aided Rolling Technology

Application, Carta®, developed by SMS Meer is the

technological production planning and process control

system for the hot section of seamless tube pro-

duction. The use of Carta® ensures compliance with

close wall thickness and diameter tolerances and

reduced material losses. The system sets standards

in profitability, productivity and tube quality.

Programmed for quality: Carta® components Carta® is designed for use in piercing mills (CPM –

Cross-roll Piercing Mill), PQF® mills (Premium Quality

Finishing) and sizing or stretch-reducing mills (SM –

Sizing Mill /SRM – Stretch-Reducing Mill). It thus

covers the whole process line in the hot section of

seamless tube production.

The structure of Carta® and its intuitive user guidance

are the same for all mill plants. That reduces the

training required and at the same increases user

confidence. Each Carta® Technology System con-

sists of the modules:

Process Planning

Process Management

Tool Management

Process Planning determines the basic settings of the

mill and the design of the tools. Process Management

provides the setting values during production, controls

the rolling process, saves process data and diagnoses

the processes. Tool Management ensures that the

tools are prepared precisely and in good time for use

in production.

From data archiving to process optimisationCarta® records all the quality-relevant data for each

individual tube during the tube production. Process

and tube quality are examined against a stored,

customer-specifically expandable evaluation logic,

e.g. by comparing actual values and nominal values.

Quality problems can thus be immediately identi-

fied and remedied. Furthermore, the long-term data

recordings or "empirical production data" provide use-

ful support for the production planning and a sound

basis for quality assurance systems.

CARTA® TeChnologY sYsTemCARTA® TeChnologY sYsTemSeamless integration, all-round innovation

2

CARTA® Technology System sms meeR

Benefits of Carta®: Increased yield

Improved tube quality

Optimisation of the mill utilisation by

• Standardised, intuitive operating concept

• Solutions for the whole seamless tube

production line

More than 80 successful references worldwide!

3

Server &Real Time Systems

CPM Process PlanningCPM Process Management

CPM Tool Management

PQF® Process PlanningPQF® Process Management

PQF® Tool Management

SRM Process PlanningSRM Process Management

SRM Tool Management

Process optimizationQuality Control

Production Control

Cross Roll Piercing Elongating Stretch-Reducing



CARTA®-CPm for PieRCing millsCARTA®-CPm for PieRCing mills Solid advantages for hollows

4


In a cone-type or barrel-type piercer,

heated solid billets are rolled out over a

piercer plug to form a hollow. This is the

first forming step, in other words the

basic form for the later tube. The hollow

is precisely guided by guide shoes or

Diescher discs. Carta®-CPM (Cross-roll

Piercing Mill) supports the plant operator

with data on tool production and selection,

on setting the mill and on controlling the

rolling process.

CPM Process PlanningCPM Process Management

CPM Tool ManagementPQF® SRM





Cross-roll piercer

Carta®-CPM Process Planning provides the necessary

information on the tools and setting data required for

a tube size range for the rolling mill. The procedure

employed follows the practice during the work pro-

cedure in the mill.

Pass size calculation: Exact guidance Specific modules calculate the pass size of rolls and

guide tools (guide shoes or Diescher discs). When

calculating the guide shoes, the optimum shoe width

is determined for the roll gap. The tools are produced

on the basis of these data.

Piercer plug calculation: Of central importanceA standard module is available for

calculation of the piercer plug. The

complete piercer plug calculation is

performed on the basis of the billet

diameter and the diameter and wall

thickness of the desired hollow –

allowing for the selected roll sizing

and guide tools.

The calculated piercer plug is repre-

sented graphically in the roll gap and

after checking by the operator can be

saved to a database. The saved pierc-

er plug data serve on the one hand

as production data for the workshop

(geometry of the piercer plug working section), and

on the other hand as setting data for the mill (roll and

guide gap, piercer plug, piercer plug position, feed

angle, rolling speed).

The calculation of the mill settings takes into consid-

eration the roll spring-back of the mill stand under

load. Different roll and guide profiles, e.g. for different

billet sizes, can be saved. The specific piercer plug

calculation, however, is unambiguously assigned to a

particular roll and guide profile combination.

Free piercer plug calculation: Freedom for individualists The "free piercer plug calculation" module is intended

for experienced users. This variant allows piercer

plugs to be freely designed. All the parameters that

determine the final piercer plug form can be freely

selected and set. A supporting system based on

empirical values provides tips so that the designed

piercer plug meets the demands of the rolling process.

CARTA®-CPm PRoCess PlAnningCARTA®-CPm PRoCess PlAnningPerfect production preparation

5

Carta®-CPM Process Planning at a glance:

Roll sizing

Guide design

Automatic piercer plug calculations

Free piercer plug calculations

Mill settings

User interface of the CPM operator station

CARTA®-CPm PRoCess mAnAgemenT

CARTA®-CPm PRoCess mAnAgemenTThe crucial hollow

In the basic version, Carta®-CPM Process

Management ensures optimised mill settings during

the rolling process thanks to global measured values

of the rolling stock geometry. Depending on the

measurement technology employed, the eccentricity

control can also be used. It has additional diagnostic

and optimisation tools. The piercing process can be

optimised by evaluating locally measured wall thick-

ness values, and hence the product quality improved,

in particular with respect to the eccentricity of the

rolling stock.

Basic version: The quality programAt the beginning of a rolling lot, the basic version of

Carta®-CPM Process Management displays all the

necessary setting values for the cross-roll piercer

from the Carta®-CPM database on the monitor. The

mill setting is then optimised using measurement

data during production. A precondition for this is a

measurement technology that calculates the mean

hollow wall thickness from the measured weight,

diameter and length values. The dimension values

are saved for each hollow and displayed graphically

on the monitor. If the measured values exceed a

given limit, a new setting is calculated and displayed

to the operator for examination. The operator can

then accept these values as the new setting values

for the mill.

The mill settings saved in the Carta® database during

production are available for future rolling lots. Further-

more, the continuously calculated feed efficiency is

displayed graphically as a trend curve. On the basis

of this information, the mill operator can decide

when the tools – in particular piercer

plugs or guide shoes – have to be

replaced due to excessive wear.

Carta®-CPM Process Management at a glance:

Basic process management

Supplementary eccentricity control (certain

measurement technologies are a precondition)

6


User interface of the operator station

7

Breakdown of the wall thickness deviations according to different causes using Fourier analysis

Eccentricity control: The optimum The Carta®-CPM/EC (Eccentricity Control) module

ensures a consistently high tube quality during day-

to-day production. It is a complement to the Carta®-

CPM Process Management. A precondition is a

measurement system that provides not only the

mean wall thickness value, but also values for each

individual hollow (or shell) with sufficient resolution

over the entire length and circumference. The Carta®-

CPM/EC system filters the measured wall thickness

deviations according to their different causes and thus

distinguishes between the influences of piercer (CPM)

and elongator (PQF®).

Using specific evaluation methods, the structures of

the wall thickness deviations hidden in the measure-

ment data are identified and the eccentricities

assigned to their causes. The information is displayed

to the mill operator and gives him a concrete indication

of the solution to the problem. Furthermore, Carta®-

CPM/EC supplies evaluation methods and applications

for defining standards for wall thickness deviations,

optimisation of the piercing (and elongation) process,

the production control and for troubleshooting and

fault remedying.

Series of 1st order (Piercing process)

Length coordinate

Length coordinate

Measuring data

Length coordinate

Series of 3rd order (Elongating process)

Length coordinate

Cross

-sect

ion

angle

Wal

l thi

ckne

ss

[mm

]

Wal

l thi

ckne

ss

devi

atio

n [m

m]

Length coordinate

Cross

-sect

ion

angle

Wal

l thi

ckne

ss

devi

atio

n [m

m]

Length coordinate

Cross

-sect

ion

angle

CARTA®-CPm Tool mAnAgemenT

CARTA®-CPm Tool mAnAgemenTOne click and the tools are fit


8

Overview of all the tools (rolls, guide tools and piercer

plugs) and immediate, reliable information for the

production of the necessary tools – that is Carta®-

CPM Tool Management. It provides both an overview

and details on the status of the individual tools.

Changes to the tool status (modified roll diameters)

can be saved in the system and are then available

centrally.

Furthermore, overviews are available for all the tools

employed for the product range. The tools can thereby

be selected and sorted according to different criteria

(e.g. all piercer plugs belonging to one roll sizing, listed

according to ascending billet diameters or hollow

diameters and wall thicknesses).

Carta®-CPM Tool Management manages:

Rolls

Guides (guide shoes or Diescher discs)

Piercer plugs

CARTA®-PQF® FoR PQF® mills

CARTA®-PQF® FoR PQF® millsEnd-to-end quality for shells

9

The PQF® (Premium Quality Finishing) mill

developed by SMS Meer currently repre-

sents the signature production method

worldwide for seamless tubes with

respect to tube quality, yield and plant

availability. In the hydraulically adjustable

3-roll stands of the PQF® mill, the hollows

are elongated to form a shell over a speed-

controlled mandrel bar. Carta®-PQF®

brings out the full process-inherent

advantages of the PQF® technology. But

Carta® also makes a substantial contri-

bution to the classic 2-roll MPM (Multi-

stand Pipe Mill) and mandrel mill (MM)

processes with respect to enhanced

quality and productivity.

PQF® Process PlanningPQF® Process Management

PQF® Tool ManagementCPM SRM





PQF® roll stand

CARTA®-PQF® PRoCess PlAnning

CARTA®-PQF® PRoCess PlAnningOptimised in advance


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Carta®-PQF® Process Planning provides the setting

values for the current sizes to be rolled. In order to

be able to calculate optimised process models for

the PQF® mill independently of the ongoing seam-

less tube production, example calculations can be

carried out on a separate planning system.

Empirical values and product data (diameters, wall-

thicknesses, steel grade), plant data (roll size, man-

drel bar) and technological parameters (model basic

data, physical model parameters) are input into the

calculation tests. The test calculations allow all the

necessary setting data for a new product to be veri-

fied prior to the production and are then immediately

ready for use in the production process.

Carta®-PQF®

Process Planning calculates: Product data

Plant data

Technological parameters

CARTA®-PQF® PRoCess mAnAgemenT

CARTA®-PQF® PRoCess mAnAgemenTThe authoritative technology

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Closer wall thickness tolerances even with high-alloy

steels, stable production of thin-walled precision tubes,

improved yield, reduced tool wear and hence reduced

operating costs – Carta®-PQF® Process Management

makes a huge contribution to allowing the benefits of

the PQF® technology to be utilised. Two systems are

responsible for this performance within Process

Management: The Process Supervising System (PSS)

and the Hydraulic Gap Control (HGC). These two

systems allow the implementation of various tech-

nological functions, such as wall thickness control

and front tail sharpening. This enables quality to be

increased and production becomes more reproducible.

Process Supervising System: Complete control The Process Supervising System brings together the

measurement values from all the areas of the PQF®

plant and evaluates them according to different cri-

teria. This “neuralgic network” supports users, tech-

nologists and maintenance engineers actively in opti-

mising production and product quality.

The Process Supervising System is practically the

"thinking" interface between the systems of the auto-

mation level 1 and the QAS (Quality Assurance System).

On the one hand it provides the operating data, and on

the other hand records all the measurement data during

the production process. The standard scanning time of

the measured values is 20 ms, but can be varied to suit

requirements. Parameters recorded are, for example,

motor values, bar position, tube temperature, roll posi-

tions and roll gaps, roll forces, technological check

values and events. The values are displayed in real time

on the operator terminal and are saved at the same

time. They can then be used for production reports and

for production data diagnosis at the mill.

Carta®-PQF® Process Management at a glance:

Process Supervising System (PSS)

Hydraulic Gap Control (HGC)

Process Supervising System (PSS)

Motor speed, voltage and current Bar position Tube temperature Roll positions and roll gaps Rolling forces Technological check values Event recording Calculation of the setting values Adaptive models Datalogger Graphic online display Ring memory for production data Technological tube report Mill diagnostics Graphic offline display (of saved tube data) Historical technological trends


12

The right setting for success The online calculation of the settings for the PQF®

mill is based on the primary data that come either

directly from the area computer (automation level 1)

or are entered by the operator via the operating system

of the basic automation. Automation level 1 generally

has a material tracking system from which the Pro-

cess Supervising System receives the setpoints and

check values. A dedicated arithmetic model carries

out the setting calculation for all primary data. The

model can take into account a wide range of working

conditions so that the set-up can be optimised for all

operating conditions.

Data Logger: Keeping tabs on the tubesThe datalogger belonging to the Process Supervising

System records information for every tube and gives

concrete feedback on the relevant quality parameters

both during and after the rolling processes. For this,

predefined or freely selected signals for the tube

currently being rolled can be displayed in real time on

the graphic online monitor.

The Mill Diagnosis function performs a technological

analysis of the production quality on the basis of the

report values. The controller automatically checks the

momentary deviation in the actual values and outputs

a warning to the operator if a deviation exceeds a

given limit value. Saved tube data can be displayed

on the "graphic offline monitor" for detailed analysis at

the technology terminal or maintenance terminal.

The "technological tube report" displays mean and

peak values for the whole length or partial length

of the tube (i.e. leading end, centre section, trailing

end), deviations between actual values and expected

values as well as start-of-rolling and end-of-rolling

time for each stand. Even an output of historical

technological trends is possible. For this, a number

of report data for a selected production period are

recorded tube-by-tube and plotted as a trend curve.

Table of the calculated setting values (example)

13

Hydraulic Gap Control (HGC): Optimum in minimumThe Hydraulic Gap Control (HGC) is a control function

for quick and precise positioning of the hydraulic roll

adjustment mechanism. It is the fundamental precon-

dition for constant tube geometries and wall thick-

nesses, and hence guarantees a high product quality.

Furthermore, it protects the mill from overloading.

Consistently high tube quality – automatically Each individual roll has independent hydraulic cap-

sules with position and pressure sensors, position

controllers and servo valves. The controller interacts

with these systems in a complex interplay. During

automatic control loops, the roll gap is measured,

actual and nominal values are calculated and the roll

gap is adjusted or corrected, if necessary. The rolling

force is measured, controlled and optimised analo-

gously. This provides a spring-back compensation of

the rolls and stand, the wall thicknesses at both tube

ends are reduced and temperature changes over

the tube length can be compensated. In order to

increase the accuracy of the roll gap and rolling force,

HGC has a servo valve compensation control system.

To explain: As there is a minimum flow of hydraulic

oil at a servo valve even in zero position (e.g. due

to minor leaks), this “interference factor” has to be

compensated during the position control. The servo

valve compensation control system performs this

fully automatically for every single servo valve and

adapts itself dynamically as the deviations change

over the course of time.

Integrated plant protection The Hydraulic Gap Control also prevents overloading

and serious consequential damage. The aim is to

complete rolling of the current shell and avoid pro-

duction standstills. Different situation-specific functions

are available for this. When force limits are reached,

the operator receives a warning signal. Predetermined

procedures ensure, for example, a slight opening

of the roll gap in the event of an overload and rapid

opening if the permissible overload is exceeded.

Hydraulic Gap Control (HGC)

Capsule position control

Rolling force calculation

Automatic flow rate control

Synchronised position control

Automatic roll gap control

Adjustment of the servo valves

Automatic zeroing of the capsule position sensors

Alarm procedures

Interfaced to automation level 1

Technological functions

Maintenance Operator Interface (MOI) mainte-nance system


14

Technological functions Technological functions are implemented using both

the PSS and HGC systems. Thanks to arithmetic

models and tests carried out on the machine during

commissioning, wall thickness control carries out a

process calculation for each rolled tube and corrects

the PSS setting.

When a wall thickness measuring device is installed,

a dedicated adaptive model calculates setting correc-

tions. The adaptive corrections are calculated after

each tube is rolled and take account of homogeneous

tube classes (i.e. tubes with the same values for dia-

meter, wall thickness, steel grade, etc.). New roll gaps

and, if necessary, roll speeds are calculated using the

identified correction values if deviations in the form-

ing behaviour occur due to unforesee able events.

Temperature variations along the shell and other

incidental effects that can lead to minor thickness

distribution deviations over the length can be com-

pensated with the use of tail temperature compensa-

tion and automatic gauge control.

The front tail sharpening function is available to

optimise the wall thickness distribution at the head

and tail ends of the pipe, allowing a drastic reduction

in the crop ends. This function performs a higher wall

thickness reduction for the ends of the pipe in order

to compensate the end thickening in a subsequent

stretch-reducing mill. Different pipe lengths are auto-

matically compensated by an online adaptive model.

MOI creates transparency The Hydraulic Gap Control has an operating system

for diagnostic purposes, troubleshooting and mainte-

nance (MOI – Maintenance Operator Interface). The

MOI permits the configuration and changes of the-

plant and control constants and their parameters.

The I/O signals, commands and settings can be dis-

played. Test point signals (and internal variables) can

also be displayed, set and transmitted to analogue

outputs in order to monitor and record the main

signals of the controller. Commands and settings

can be entered to easily check the system and

remedy faults, if necessary. Finally the MOI allows

the response behaviour of stepping and frequency

systems to be checked and the flow rate for each

hydraulic capsule position to be optimised.

Example of the graphic representation of measured data

15

The optional Carta®-PQF® Tool Management orga-

nises the preparation and operation of the tools for

the elongating mill: The PQF® rolls and mandrel

bars. The system provides the PQF® redressing

machine and mandrel lathe(s) in the workshop with

the technological data for machining these tools and

supplies the actual machined dimensions of the rolls

and the mandrel bars, which are prepared for pro-

duction, to the process management system (PSS).

On the basis of the actually machined roll diameter

and the selected mandrel bar diameter, the actual

setting data during production are calculated in the

process management system. The information on

the number of tubes rolled on the tools used during

production and the most relevant rolling parameters

are stored in the system in order to have the history

of operation of the tools available for evaluation and

maintenance.

CARTA®-PQF® Tool mAnAgemenT

CARTA®-PQF® Tool mAnAgemenTThe skilled automatic organiser

Advantages of Carta®-PQF® Tool Management:

Automatic organisation of tools

Technological data for tool machining

Interfaces with PSS for preparation

of production

Complete recording of tool applications

PQF® groove dressing machine

CARTA® Technologiesystem sms meeR

16

CARTA®-sRm FoR sizing AndsTReTCh-ReduCing mills

CARTA®-sRm FoR sizing AndsTReTCh-ReduCing millsLengths ahead of the rest

The last forming step for the seamless

tubes is performed on the multi-stand

sizing mill (SM) or stretch-reducing

mill (SRM). Here the tubes are rolled

to the desired outside diameters and

wall thicknesses and thereby elongated

at the same time. The speed control

ensures close wall thickness tolerances.

Optional adjustable stands maintain very

tight diameter tolerances. Carta®-SRM

provides complex technologies for this.

They comprise the Process Planning,

Process Management and Tool Manage-

ment. These technological tools merge

the decades of competence and the

latest know-how of SMS Meer – a

combination offering cost-effectiveness,

reliability and future viability for the plant

owner.

CPM PQF®





SRM Process PlanningSRM Process Management

SRM Tool Management

SRM roll stand

17

CARTA®-sRm PRoCess PlAnningCARTA®-sRm PRoCess PlAnningBetter results – faster

The Carta®-SRM Process Planning system component

performs the setting, optimisation and management

of roll pass and rolling programme data. The com-

puter-aided technological tool relieves and supports

the mill operator and significantly accelerates the

preparation for the rolling process. The system is

based on SMS Meer’s modern technologies and

proven computation methods and provides them in

the form of modules.

Exact planning of rolling processes The reduction pass series module contains the

nominal diameters of the passes in the mill stands.

The pass diameters for the starting, working and final

stands for the finished tube sizes to be produced are

calculated. The yield stress (material tensile strength)

of the rolling stock for certain rolling process con-

ditions is determined by the material data module. In

addition it performs a rough calculation of the stand

load.

Carta®-SRM Process Planningat a glance:

Reduction pass series

Material data

(determination of the yield stress)

Setting and process data

Groove planning

Free groove forms


18

The setting and process data module is essentially

used for calculating the roll speeds. The calculation is

based on a proven arithmetic-physical model of the

stretch-reducing process. At the end of the process

calculation, a table is displayed with the most impor-

tant forming parameters that allows the planned roll-

ing process to be assessed. An additional calculation,

e.g. calculation of the lengths and weights of the

thickened ends, is also possible.

Avoid internal polygonisationThe stand groove planning module generates the tool

and setting data for round and oval pass forms and

transmits the data to the groove dressing machine in

the stand workshop.

A specific, process-inherent quality problem during

stretch-reducing is “internal polygonisa tion”. This

problem has been solved in many areas, however,

through the introduction of unconventional Free

Groove Forms (FGF). Free groove forms are cut on a

CNC groove dressing machine. They are constructed

as geometric elements and transmitted to the groove

dressing machine as coordinate values.

Better quality with free groove form

Konventionelle KaliberformFree Groove Form (EP 0854 762 / US 6065320)

Conventional Groove Form

19

CARTA®-sRm PRoCess mAnAgemenT

CARTA®-sRm PRoCess mAnAgemenTComplex systems for constant wall thicknesses

Carta®-SRM Process Management results in improve-

ments in the wall thickness tolerances on the finished

tube, and hence in increased yields. The cost savings

or increased profits can amount to several percent of

the annual production.

The compensation of wall thickness deviations is

predominantly achieved through selective changes in

the roll and motor speeds. The planned static basic

speeds are first entered by the plant operator at the

mill operating system. These automation data are

technologically planned and can be called up from

the rolling programme database. Both the static

and the dynamic superimposition speeds are then

transmitted to the drives by the Carta® Real Time

System.

Carta®-SRM Process Management provides various

effective functions for avoiding wall thickness deviations.

CEC reduces crop end losses Crop End Control (CEC) can reduce crop end losses

by over 50% and thus improve the yield of the rolling

mill by up to 3%, depending on the rolling programme.

It prevents or reduces the wall thickness increases

occurring at both ends of the tube during stretch-

reducing. In order to achieve this, the roll speed

ratios are increased at each end of the tube, resulting

in greater elongations. The CEC is configured for dif-

ferent drive types. The CEC system can be adapted

individually to take account of empirical values and

particular rolling conditions. The operator can, of course,

carry out a direct modification during rolling to further

optimise the effect of the CEC at the tube ends.

Carta®-SRM Process Management at a glance:

CEC – Crop end control

WTCA – Wall thickness control, average

WTCL – Wall thickness control, local

SDC – Speed drop compensation

ESC – Exit speed control

TLC – Tube length control

MLC – Motor load control

Process visualisation

Immediate diagnostics

Process and control data recording

Data archiving (optional)


20

WTCA and WTCL for constant wall thicknesses The wall thickness control systems WTCA (Wall

Thickness Control, Average) and WTCL (Wall Thick-

ness Control, Local) reduce wall thickness deviations;

in other words, these systems effectively improve

the tube quality. If the deviation in the average wall

thickness of the shells is for example ± 3%, the

finished tube rolled with the wall thickness control

systems has a wall thickness deviation of only ±1%

or less.

The main difference between WTCA and WTCL lies

in the greater precision of WTCL. While WTCA influ-

ences the average wall thickness over the whole

shell length, WTCL intervenes to correct even local

deviations. This greater precision is made possible

by a small range of changes in elongation. In other

words: The coarse setting of the wall thickness con-

trol is made with WTCA, the fine tuning with WTCL.

With WTCA the roll speed ratios are increased or

decreased, depending on the measured devia tion

from the average shell wall thickness. This change

results in a selective and precise tube wall thickness

behind the rolling mill.

WTCL can reduce localised deviations from the

average wall thickness by either increasing or reducing

the roll speed ratios in the mill over the whole shell

length. The local wall thickness control is geared to

the respective drive and the current stand setting

plan. Of particular note here is that a small number of

stands can compensate small deviations in wall thick-

ness, while a large number of stands can correct

large wall thickness deviations. One variant of

WTCL is WTCLL (Wall Thickness Control, Local,

Light) that requires no shell measurement data but

can still achieve a reduction in the local wall thick-

ness deviations on the finished tube.

Thickened tube end Average wall thickness Local wall thickness

Tube length Shell length

Roll s

pe

ed

s

Roll s

pe

ed

s

Roll s

pe

ed

s

WTCA WTCLCEC

Shell length

Nominal wall thickness

Nominal speeds

CEC-speeds dynamic

WTCA-speeds static

WTCL-speeds dynamic

Effect of the control functions

21

The Tube Length Control system (TLC) is an alterna-

tive function for wall thickness control. TLC ensures

a constant good tube length from tube to tube, even

if the ingoing lengths and wall thicknesses entering

the rolling mill vary. Instead of maintaining a constant

tube wall thickness with WTCA, TLC ensures a con-

stant tube length with varying wall thicknesses.

Motor Load Control (MLC) automatically reduces load

peaks on the motors and thus helps to fully utilise

the potentials of the rolling mill with respect to larger

wall thicknesses and higher alloy materials.

Further control functions The Speed Drop Compensation function (SDC) reduc-

es the drop in motor speed that occurs when the

tube contacts the rolls of the individual stands. The

objective of Exit Speed Control (ESC) is to achieve a

constant run-out speed of the tube leaving the rolling

mill in order to ensure the precise and safe operation

of a rotary saw.

Process visualisation and immediate diagnostics The operator at the operator terminal can monitor

whether the rolling process is running smoothly within

the given tolerances thanks to the visualisation system.

All the latest information can be called up here in a

clear form, for example display of the tube passage,

measurement data and actions of the motors, process

data, results of the diagnostic functions, validation of

the measurement data, correct sensor function and

naturally compliance with the wall thickness tolerances.

21.3 ... 31.8 33.7 ... 114.3 114.3 ... 141

Finished tube diameter in mm

Cro

p lo

sses

(rea

r en

d) in

m

7

6

5

4

3

2

1

0

WITHOUT CEC WITHOUT CEC

WITH CEC WITH CEC

The CEC-system reduces crop end losses


22

Process and control data recording The relevant data for evaluation of the rolling process

and the control functions for each rolling process are

recorded, saved and made available at the technology

terminal by the "process and control data recording"

module. These include, for example, wall thickness

measurement data, setting data and computation

data. The actual evaluation can be carried out using

commercially available spreadsheet calculation pro-

grams. For capacity reasons, the data storage on the

Carta® SRM main computer is limited to roughly

one week of production. As an option, the Carta®

Archiving Server is available for data archiving.

Data archiving: Long-term data security The optional Carta® Archiving Server permits reliable

storage of recorded production process data for an

unlimited period. The information and evaluations can

be easily visualised using the comfortable software

tools of the Carta® Database Browser.

The server can hold large volumes of data, such

as measurement data on shells and tubes, motor

speeds and currents, user inputs and computation

data. These data allow conclusions to be drawn as

to production and product quality. Either all the pro-

cess data or only the process data selected using

filters can be saved. The data are stored for roughly

one year on hard disk and then transferred autom a-

tically to a tape drive. Data already transmitted can

be transferred back to the system and hence made

immediately available again.

From analysis to planning optimisation – automaticallyThe process data are analysed automatically after

every rolling lot and transferred in condensed form to

the optimisation database. The database thus reflects

the mill operation and the production results, e.g.

with wall thickness deviation and yield figures. This

feedback of production information to the planning

system then allows the planned mill setting data to

be optimised.

Example of a process visualisation

23

CARTA®-sRm Tool mAnAgemenT

CARTA®-sRm Tool mAnAgemenTThe set-up tool for all stands

Carta®-SRM Tool Management organises, system-

atises and rationalises roll dressing in the stand

workshop and stand operation in the stretch-reducing

mill. It increases the safety standards, maximises the

flexibility of the stand operation and improves the

use of the available roll stands and roll sets. These

advantages come particularly to bear when a broad

range of different products with frequently changing

product dimensions has to be rolled on the stretch-

reducing mill.

Advantages of Carta®-SRM Tool Management:

Greater reliability in the roll/stand operational

planning and dressing of the stands

Optimised roll operation

Improved preventive maintenance

Greater availability of the stands

Reduced personnel requirements

Improved product quality

STAND DATA MANAG.

Select pass series

Select machining data

STAND SETTING PLAN

Groove data Measuring data

GROOVE DRESSING

MACHINING LIST

Display schedule Activate schedule

STAND POS. ALLOC.

Number of passes

PROCESS DATA

CARTA -SRM/TOOL MANAGEMENT

Stand Workshop

KR CNC Mill operation

®

Schedule of orders

CARTA -SRM/ Groove Planning

®

Tool management structure


24

Source and distributor of information Carta®-SRM Tool Management provides an intelligent

information highway between technology office,

workshop and rolling mill. For example, the stand

workshop receives reliable information on the nominal

data for the pass series (groove nominal diameters

and stand setting plan) and on the roll sizing (groove

dimensions, tool dimensions and setting). At the

same time, the system manages the status descrip-

tions of the physical stands (including roll material,

current groove sizes and number of passes). The

advantage for the stand workshop is that thanks to

the logical combination of technological data and

stand data, the system provides suggestions for the

stand dressing to be carried out according to the

order plan.

Practical and practice-oriented For the stand dressing, Carta®-SRM Tool Management

has structured functions adapted to the work in prac-

tice. The basis for this is the stand data management

with the roll stand inventory list. It contains information

such as on roll material, intended use, current pass

size, operational history and current location for every

single stand. Using the stand setting plan it is possible

to select the starting, intermediate and final pass

data from the central database and to allocate these

to suitable stands for dressing. In the dressing list,

the dressing data (tool and setting data) are then

assigned to the stands. Then the rolls are machined

usually on a KR CNC lathe. Dressing data and measure-

ment data are assigned to the stands and saved.

Before the start of production, the positioning of the

individual stands in the mill is displayed. The operator

can change and then activate the positions, in other

words signal back to the stand management module

that the stands are "in rolling operation".

Using the "Process data" function, for example, the

number of rolling cycles is assigned to the respective

installed stands. This allows the wear condition of

the rolls to be determined. This information is fed

back to the Tool Management module.

SRM/SM groove dressing machine

25

View off a modern PQF® plant


26

SMS Meer seamless tube mills are tai-

lored to your individual requirements. Our

product range offers you a broad choice

of different performance parameters.

We can therefore offer you configurations

in which all the components are ideally

tailored to one another – both technically

and economically.

sms meeR gmbh

Ohlerkirchweg 66 41069 Mönchengladbach Postfach 100645 41006 Mönchengladbach Germany

Tel.: +49 (0) 2161 350-0 Fax: +49 (0) 2161 350-1667

[email protected] www.sms-meer.com

sms demAg innse s.P.A.

Via Rubattino, 87 20134 MilanoItaly

Tel.: +39 02 2124-1 Fax: +39 02 2154-699

[email protected] www.innse.com

YouR needs –YouR needs –our solutions

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sms meeR gmbh

Ohlerkirchweg 66 41069 Mönchengladbach P.O. Box 100645

41006 Mönchengladbach Germany

Tel.: +49 (0) 2161 350-0 Fax: +49 (0) 2161 350-1667

[email protected] www.sms-meer.com

meeTing your exPeCTATions

The information provided in this brochure contains a general description of the performance characteristics of the products concerned. The actual products may not always have these characteristics as described and, in particular, these may change as a result of further developments of the products. The provision of this information is not intend-ed to have and will not have legal effect. An obligation to deliver products having particular characteristics shall only exist if expressly agreed in the terms of the contract.

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