TUBING MILL MANUFACTURING PLANT

 

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Allstate's Of America, Inc.  2595 N.W 37TH. ST. MIAMI, FLORIDA, 33142 USA 800 223 2573,   305 635-4525  Fax 305 635-5353      e-mail    Bob@allstates.com                http://www.allstates.com

 

 

 

 

 

Specification of Standard Tube Mill

Modle

Tube O.D (mm)

Wall Thickness (mm)

WNT-50A

25.4 ~ 63.5

1.2 ~ 4.5

WNT-70A

31.8 ~ 76.3

1.4 ~ 6.0

WNT-100A

34.0 ~ 114.3

2.3 ~ 7.1

WNT-130A

42.7 ~ 139.8

2.3 ~ 8.1

 

 
 

        DOUBLE DRUMS AND SWIVEL UNCOILER

         

        Function:

                                Uncoiler takes the strip from overhead crane and unwinds to feed the coil into the line.

         Specification:

        Feed speed into the looper

        Max. strip weight

        Strip width

        ID of strip

         

         

         

         

        Operation:

               A coil is mounted on an expansible drum using an overhead crane while the other one is in operation. When the working strip is unwound off from the drum, operator turns the uncoiler upper frame so that new coil can be fed into the line.

         

         Construction:

                 Lower frame made of heavy-duty welded steel supporting swivel double drum upper frame.

                    Slewing upper frame is driven by hydraulic motor.

                 Slow start and stop motion are made by hydraulically operated brake valve mounted

                  under solenoid during slewing motion.

               2 hydraulically expansible and collapsible link type drum made of cast iron.

              Disk brake operated by air-oil converter enables the strip to be fed with appropriate back-tension.

              Heavy-duty slewing bearing equipped with spur gear on outside ensures smooth movement

                of turning.

 

 

c

          Cu                     SHEAR AND WELDER                                                                            cuts the wrong part of leading and trailing end of the strip and welds both ends for

                                          continuous operation of tube mill.

         

        Newly developed STRIP-END WELDER is a new generation of welder

        for joining strip-end to strip-end and has following characteristics.

         

        1. Quick and correct cutting by pneumatic cylinder

                        2. Automatic TIG welding ensures stable and relatively little bead of welded part

        3. Very easy operation

        4. Very economical for investment and operation

         

        COMPOSITION

        1. Movable 4-wheeled cart

        2. Pneumatically operated shear

        3. TIG welder

        4. Variable speed drive for welding torch

        5. Pneumatically operated clamping device

 

 

 

 

 

 

 

 

        ROTARY LOOPER

         

        Function:

                Stores the strip to ensure continuous operation of the tube mill.

 Specification:

Model No.

Strip thickness

Strip width

Incoming speed

Outlet speed of strip

Storage capacity

Entry pinch drive

Rotary drum drive

Dimension (Approx.)

         

        Operation:

                                            This equipment is used for accumulating the strip to be fed into the line without stopping

                                              the line during butt welding of both ends of the strip.

         

                The strip will be accumulated on stationary inner drum and outer drum of the

                  ROTARY LOOPER by means of rotation of the rotary drum. The rotary drum is driven

                  and controlled  by AC servomotor. And the AC servomotor also is simultaneously controlled

                  by entry pinch roll  and exit guide roll speed.

         

                Required length data of the strip for accumulating to be used during welding time is stored

                  in electronic controller by operator, and target sensor, which is mounted on the outer basket,

                  detects the number of wound turns and sends its feed back signal to the controller.

                  If required length is accumulated as directed, the controller automatically stops rotation

                  of the rotary drum.

         

                If more strips to be accumulated are needed compared with the stored length data,

                  which is determined by operator and stored in the controller, the rotary drum rotates fast till

                  the strip is accumulated full. When the wound strip is too tight or too loose,

                  another sensor detects    the tightness of wound strip coil and controls it to be wound

                  appropriately.

         

               The rotation speed of the rotary drum is also controlled according to the mill speed.

                 This mill speed is detected by an encoder mounted on exit guide roll.

         

               The stored strip is then fed into the mill through spiral drum, on which a number of cylindrical

                 guide rolls are mounted for the strip support.


 

        Construction:

        One (1) robust main frame made of welded steel

             One (1) inlet pinch roll driven by variable speed DC motor and guide rolls

             One (1) rotary drum mounted in anti-friction bearings and driven by AC servomotor

        One (1) outer basket composed of vertically mounted cylindrical rolls

        One (1) inner basket composed of vertically mounted cylindrical rolls

        A number of side guide rolls controlled by an AC geared motor

        One (1) outlet horizontal deflector roll and measuring rolls

             Three (3) optical sensors for detecting winding turns, coiled strip tightness and home position

              of the rotary drum

             Two (2) rotary encoders to detect required strip length and accumulation speed

 

 

        FORMING SECTION  This section is composed of:

         

        Guide roll ----------------------------------- 1 set

        Side guide rolls & leveler -------------- 2 sets

        Forming vertical stands ---------------- 4 sets

        Forming side roll stands -------------- 3 sets

        Clustered side roll stands ------------ 2 sets

        Fin-pass vertical stands --------------- 3 sets

        Fin-pass side roll stands -------------- 2 sets

        Driving gear box -------------------------- 7 sets

         

        GUIDE ROLL

         

        Function:                     Guides the strip incoming from the accumulator to the tube pass level.

         

        Specification:

        Roll size

         

         

         

         

        Construction:           Two (2) horizontal steel rolls are supported by anti-friction bearings mounted on a support frame.

        This guide roll unit is mounted on the entrance side of main bed.

         

        SIDE GUIDE ROLL & LEVELER

         

        Function:                    Adjusts the centerline of the strip by means of hand-wheels and screws.

        Flattens the strip to facilitate forming.

         

        Specification:

        Side guide

        Type

        Roll materialAlloy tool steel (SKD - 11)No of RollsFour (4)LevelerType3-Roll typeDriveIdleRoll materialAlloy steelRoll arrangementTop - 1, Bottom - 2

         

        Construction:            Side Guide Rolls

          - The side guide rolls are provided at the entry side of forming section.

            2 Roll chocks move horizontally or centrically in a box type housing by

             a manually operated wheel and a threaded shaft, which has right and left-hand thread on it.

                  - Each roll has grooved home which exactly guides and shaves sharp edges of the slit strip.

                         These rolls are made of hardened alloy tool steel to prevent from rapid weariness.

         

        Leveler

                       - The leveler facilitates the strip entering and forming at the first stage of breakdown part.

                          Composition

          1 Heavy-duty welded steel frame

          3 Hardened and ground alloy steel rolls

          1 Height adjustment screws mounted in upper roll housing

         

        BREAKDOWN VERTICAL STANDS

         

        Function:                     Forms the strip into tubular shape progressively. 

         

        Specification:

        Roll shaft diameter

        Roll root diameter

        Roll shaft material

        Roll Adjustment

        Roll shaft bearing

        Inboard stand

        Outboard stand

        Stand material

        Drive

        Drive connection

         

         

        Operation:                 The strip passes between the upper and bottom roll of each stand, all these rolls

          are driven by DC motor. When changing the rolls, the operator unscrews the nuts engaged

          on the threaded end of roll shafts and pulls the outboard stand out.

         

         

        Construction:            Four (4) stands are provided. All stands are all identical which are made of cast iron.

           Each stand is composed of inboard and outboard housing. Outboard housing is moved off from

           the shafts to facilitate roll changeover.

         

        Rolls are mounted on the top and bottom shafts, which are driven by DC motor through

          universal joints and gearboxes, and are positioned at the right center by the spacers.

         

        In the cap of the stand, a set of manually operated single point screw jack is provided to move

          the upper roll for height adjustment.

         

        Heavy-duty taper roller bearings mounted in inboard stand carry the shafts and roller

          bearings rotating in hardened sleeves are mounted in outboard stand.

                        

                                                  In front side of each stand, precisely graduated scale is provided for operator's convenience.

         

        FIN-PASS VERTICAL STANDS

         

        Function:                  Finally forms the strip into open-seam round tube and keep it in upright position.

         

        Specification:

        Roll shaft diameter

        Roll root diameter

        Roll shaft material

        Roll Adjustment

        Roll shaft bearing

        Inboard stand

        Outboard stand

        Stand material

        Drive connection

         

         

         

         

        Construction:           The same as forming stands but fins are provided between 2 pieces of the upper rolls to

          guide the open seam to center position and three (3) stands are provided.

         

        FIN-PASS SIDE ROLL STANDS

         

        Function:                   The side rolls in both sides hold the strip tightly to maintain the formed

        shape and prevent the spring back of the edges of coil.

         

        Specification:

        Roll shaft diameter

        Roll shaft material

        Side roll bearing

         

         

         

         

        Construction:          The side roll stands of fin-pass part are the same as them of breakdown part.

         

        DRIVING GEAR BOX

         

        Specification:          Type Worm & helical gear type

        Worm material Alumi-bronze (AlBC2)

        Coupling Chain coupling type

        Lubrication Forced circulation

        Oil cooling By heat-exchanger with water

         

        WELDING SECTION   Welding section is composed of;

         

        Seam guide --------------------------------------- 1 set

        High frequency welder ------------------------- 1 set

        Squeeze roll -------------------------------------- 1 set

        Bead scarf unit & bead winder --------------- -- 1 set

        Ironing roll stand --------------------------------- 1 set

        CT stand ------------------------------------------- 1 set

        Water cooling --------------------------------- 1 set

         

        0x08 graphic
         

         

        SEAM GUIDE

         

        Function:                     Finally centers and maintains required gap of both edges of the strip just before welding.

         

         

        Specification:

        Up-down moving range

        Feed-back moving range

        Angle of seam moving

         

         

         

         

        Construction:          The main housing of the seam guide made from welded steel is mounted on the main bed.

         

        2 Intermediated plates are mounted on the main housing and are adjusted in line flow

           and perpendicular directions respectively. The roll holders provided on upper and lower side of

           the tube adjust the open seam by means of worm and worm wheel, which is machined on

           the circumference of the roll holder. The upper roll is provided with fin for guiding the seam and

           the lower roll without fin supports the bottom side of the tube.

         

        Each roll is mounted in a chock respectively, which is moved in vertically machined roll holder.

         The seam guide main housing is adjusted in both directions of the pipe flow, forward

         and backward, thus enable to adjust exact gap for welding.

         

        HIGH FREQUENCY WELDER ( Out of scope of supply)

         

        SQUEEZE ROLL

         

        Function:                     Squeezes precisely both edges of the strip which have been heated by the welder.

         

        Specification:

        Type

        3-Roll type

        Roll arrangement

         

        Top

        2 Roll

        Side

        1 Rolls

         

         

         

         

        Construction:             Both edges of the strip completely formed in tubular shape is squeezed precisely and laterally    by 3 guide rolls.

         

        Three (3) guide rolls are mounted on the specially made lathe chuck type holder,

          of which 3 slides are simultaneously operated with single point mechanism.

         

        This lathe chuck type squeeze roll holder slides vertically in the welded steel structure frame    for pass-line adjustment.

         

        Because of one (1) holder comprising all 3 rolls with heavy-duty roll brackets,

          roll shafts would not to be bent passively caused by spring back of the strip.

 

        BEAD SCARFING UNIT AND BEAD WINDER

         

        Function:                     Removes outside bead of the tube and winds it on a rotating drum.

         

        Specification:            No of tool holders Two (2)

        Quick lifting By pneumatic cylinders,

         

        Construction:           Bead scarf unit

             Two (2) tool holders are mounted on a frame, and are operated and adjusted separately.

               Each outside bead scarf unit consists of tool holder, sliding plate and a frame made

                of welded steel. The tool holder is vertically and horizontally adjusted by manually operated  threaded shafts.

              Quick lifting devices of the tool holder actuated by air cylinder are provided for emergency.

         

        Bead winder

          Bead scrap is wound on a rotating drum, which is collapsible by air cylinder.

         The rotating drum is driven by an AC geared motor through worm gearbox and friction pad.

          By this friction pad, excessive rotating force can be reduced.

        0x08 graphic
         

         

        IRONING ROLL STAND

         

        Function:                    Thickens the welded seam of tube outside after the bead is removed.

         

        Specification:

        Roll shaft diameter

        Roll root diameter

        Roll shaft material

        Roll Adjustment

        Roll shaft bearing

        Inboard stand

        Outboard stand

        Stand material

        Drive

         

         

        Construction:            The function and construction are the same as the forming stands. 2 roll shafts are all idle.

         

        C.T STAND   (Out of scope of supply)

         

        WATER COOLING

         

        Function:                     Cools down the temperature of the tube heated by the welder while it passes trough the  water shower bath.

         

        Specification:           Length 5,000 mm

         

        Construction:             The water cooling includes welded steel tank and perforated pipe which supply the water shower.

         

          Idle rollers adjustable are provided in the tank to support the tube processed.

         

        SIZING SECTION        This section is composed of;

         

        Sizing 2-roll vertical stands --------------- 2 sets

        Sizing side stands -------------------------- 2 sets

        Sizing 4-roll vertical stands ---------------- 3 sets

        Turks head stands ------------------------- 1 set

        Measuring roll ------------------------------- 1 set

        Driving gear boxes --------------------------- 5 sets

         

        SIZING 2-ROLL VERTICAL STANDS

        Function:                     Finalizes the size and roundness of the tube.

        Specification:

        Roll shaft diameter

        Roll root diameter

        Roll shaft material

        Roll Adjustment

        Roll shaft bearing

        Inboard stand

        Outboard stand

        Stand material

        Drive

        Drive connection

         

         

        Construction:          Two (2) stands with horizontal shafts are provided.

        The functions and construction are the same as the fin-pass stands.

         

        SIZING SIDE STANDS

         

        Function:                    Holds the tube tightly to maintain the formed shape.

         

        Specification:

        Roll shaft diameter

        Roll shaft material

        Side roll bearing

         

         

         

         

        Construction:            Two (2) Stands are provided. Each stand is positioned between 2 sizing vertical stands.

          Other features are the same as the fin-pass side cluster.

         

        SIZING 4-ROLL VERTICAL STANDS

         

        Function:                     Shapes the round tube into square or rectangular.

         

        Construction:

        Three (3) Stands are provided.

         

        Except side roll chocks, which are incorporated in the 4-roll vertical stands,

          other function and constructions are the same as 2-roll vertical stand.

         

        Side roll chocks are operated horizontally and vertically through manually operated screw.

         

        TURKS HEAD STANDS

         

        Function:

        Straightens the tube when it leaves the sizing stand.

         

         

        Specification:

        Up-down moving range

        Left-right moving range

        Turning range of roll holder

         

         

        Construction:           One (1) stand are provided, which are fabricated with heavy-duty steel structure.

         

        The No.1 turks head stand is composed of four (4) rolls on both entry and exit sides.

           By the turks head arrangement, the tube can be straightened without additional  straightening machine.

         

        Each four (4) rolls are vertically and horizontally adjusted by manually operated screws and

           are turned by worm and worm wheel. All rolls are idling on the roll shaft.

         

        MEASURING ROLL

         

        Function:                  Measures the tube length to be cut and sends the signal to the DDS system of the   cut-off machine.

         

        Specification:

        Roll diameter 127.324 mm

        Linear length per rev. 400 mm

        Hysteresis 0.08 mm/pulse

        Transmitter PG5000 PPR

        Roll pusher Air cylinder

         

        406. DRIVING GEAR BOX

         

        Specification:

        Type Worm & helical gear type

        Worm material Alumi-bronze (AlBC2)

        Coupling Chain coupling type

        Lubrication Forced circulation

        Oil cooling By heat-exchanger with water

         

        CUT-OFF SECTION

         

        501. FLYING CUTOFF MACHINE

         

        Function:                    Cuts to length the tube by means of circular saw blade and DDS system.

         

         

        Specification:

        Type

        Cutter traveling distance

        Traveling device

        Type

        Maximum Speed

        DC Servo motor

        Cut-off device

        Circular speed of saw

        Saw motor

        Cutting

        Clamping

         

         

        Description:

        The flying cutoff machine is of full automatic operation.

           The carriage, which is driven by DC servomotor, is traveling at the same speed as the tube

           coming out from the sizing mill. The tube is clamped by pneumatic cylinder and cut by rotating saw,

           which moves down from the top side of the tube by pneumatic cylinder.

         

        The carriage returns to home position at higher speed than the traveling speed for cutting.

          The saw blade is driven by AC motor, and is mounted on the carriage. DDS system accurately

          controls the cut-to-length.

         

        Construction:           Fixed base equipped with 2 rails on it and made of welded steel

         

        Mechanical stopper provided on the fixed base for emergency

         

        Traveling carriage provided with 4 wheels

         

        4 Guide wheels mounted on the carriage

         

        Precision rack and pinion driven by DC servo motor

         

        Circular cold saw blade driven by AC motor is swung by pneumatic cylinder

         

        Pneumatically operated 2 clamps are mounted very closely to the saw blade

         

        RUNOUT TABLE & TUBE POCKET

         

        Function:                   This table receives the cut tubes and discharges them out of the line.

         

        Specification:          Table length 12,000 mm   

         

        Kick-out 2 - way, operated by hydraulic motor

         

        Roll drive AC 7.5 kW x 4 P   

         

        Tube pocket Welded steel structure with flat belt

         

        Construction:          Great number of V-rollers conveys the tube at higher speed than the line.

           The speed of the roller table is controlled by means of inverter controller.

         

        Each roll is supported by anti-friction bearings, which are mounted on welded steel table.

         

        Kick-out devices discharge the tube in 2 directions.

          Hydraulic motor drives the kicker when the tube is detected by sensor mounted on the table.

         

        The tube pocket is installed at the exit side of the run out table, and is made of welded steel.

           Inside the tube pocket flat belts are provided for shock absorbing.

         

        ELECTRICAL EQUIPMENT FOR TUBE MILL LINE

         

        GENERAL CONDITIONS

         

        Design standards    All equipment and work covered herein including design, fabrication, testing, ratings,

        etc. will comply with the applicable sections of current editions of the following codes and standards.

         KS Korean Industrial Standards.

         IEC International Electrotechnical Commission

         

        Electrical subcontractor(Supplier) All specified electrical equipment and process control systems will be based on the following

                                             subcontractors (suppliers)

        - Power and drive systems

        - Process automation

        * PLC and subsystems maker LG

        Engineering for power and drive systems will be done by subcontractor, engineering and software for process control will be carried out by Wonjin Industrial Co., Ltd.

         

        Network conditions Power supplies will be designed based on the following nominal voltage levels :

        AC power :

        - Low voltage To be recommended by the Buyer ; 50 Hz 1 Hz , 3 Phases, 4 wire

        - Short circuit level 30KA

        AC power :

        - Control source volt. 220 V AC

        - Solenoid valves 220 V AC

         

        Site conditions          All electrical equipment and apparatus will be suitable, both electrically and mechanically, for industrial service.

        Operating conditions :

        - Temperature

        In electric rooms + 5℃ to +35℃

        In control rooms + 5℃ to +30℃

        Outside of rooms - 5℃ to +40℃

        - Humidity Max. 80 %

        - Altitude Max. 1,000 m

         

        LINE DRIVE

         

        Variable speed DC drives DC motors will be separate excitation or permanent magnets. All motor are of industrial design

                                     for use under rough industrial environmental condition.

        The rating of all motors is in accordance with IEC.

        - Rated power Acc. to requirements

        - Design of protection Drip proof self ventilated IP23S

        - Cooling IC 06

        - Rated voltage xxx V, 3-phases

        - Armature voltage xxx V

        - Rated speed Acc. to requirements

        - Insulation Class F

        - Mounting Foot mounted B3

        - Bearing Ball bearings

        - Accessories Temperature sensor (thermostat)

        - Overload capacity 150%, 1 min

        Equipment to be provided One (1) lot,

         

        Speed controllers for DC motor

         

        The double bridge three phases variable speed controllers are designed for the speed regulation

        of 2.2 to 1,300 kw DC motors with separate excitation.

        Characteristics

        - The speed controllers enable operation in all 4 quadrants of the torque/speed range.

        - From the 800A rating upwards, it is fitted with a field current regulator.

        Speed range

        - Regulation by armature voltage accuracy 1 to 20

        - Regulation by tachogenerator accuracy 1 to 300

        - Regulation by incremental encoder accuracy 1 to 3000

        Acceleration and deceleration ramps

        - Acceleration and deceleration independently adjustable from 0 to 999.9.

        Reversal

        - Solid state reversing in all 4 quadrants

        Braking

        - By regenerative braking

         

        Speed variable AC motors

        AC motors will be squirrel cage induction type. All motors are of industrial design for use under

        rough industrial environmental condition

        The rating of all motors is in accordance with IEC.

        - Rated power Acc. to requirements

        - Design of protection Totally enclosed IP 54

        - Cooling Surface cooled with shaft mounted

        fan IC 0141 or independent fan

        IC 0641 acc. to requirements.

        - Rated voltage xxxV, 3-phases

        - Rated frequency 50 Hz

        - Rated speed Acc. to requirements

        - Insulation Class B, temperature rise B

        - Mounting Foot mounted B3 Flange mounted B5 or as indicated.

        - Housing material Cast iron otherwise welded

        - Bearings Ball bearings

        - Accessories Gears (if required)

        - Overload capacity 150 % , 1 min

        Equipment to be provided

        - One (1) lot, AC motor according to motors and components list.

         

        Speed controllers for AC motors

        The system consists of individual inverter units each connected to the AC motors.

        Power technology

        Diode bridge with high Ⅰ2t

        - Rugged to withstand harsh environments

        Inverter : 2.2 to 7.5 kW - IPM - Intelligent Power Module

        = IGMT + integral protection 11 to 220 kW - IGBT

        - Significant increase in product reliability

        - Reduction in switching losses

        Switch mode power supply

        - New functions

        - Rugged to withstand harsh environments

        Isolated power and control

        (high impedance isolation used for measurement of supply voltage and DC bus voltage)

        - Solution providing simplified EMC conformity

        (Electro Magnetic Compatibility)

        Control technology

        High level of integration

        Significant reduction in the size of the control card

        - AISC

        One use for digital functions ; Motor control, PWM generation, detection of tripping faults

        One use for analogue functions ; Management of analogue inputs, measurement of

                                                     motor voltage

        - Surface mount technology

        - Multilayer circuits (4)

        Designed for high MTBF

        - 16 Bit micro processor, 40 MHZ, 100ns average cycle time, pipeline architecture

        Functions; Calculation of regulation algorithm, monitoring, faults.

        I/O management, man-machine dialogue.

        - Real-time kernel for a "product" and "option" software structure.

        - Plug in customer connectors.

        - Communication cards and dedicated PCMCIA cards

        (Personal Computer Memory Card International Association)

        - IP 20 cards (Protected against finger contact)

        Drive parameter programming and diagnostics

        Each drive will include a drive-related operation graphic terminal.

        - 64 x 128 pixel, ie 6 lines of 21 characters

        - LCD screen (40 x 70 mm)

        - Back list screen

        - 20 keys

         

        Fixed speed AC drives

        AC motors will be squirrel cage induction type.

        All motors are of industrial design for use under rough industrial environmental conditions.

        The rating of all motors is in accordance with IEC.

        - Rated power Acc. to requirements

        - Design of protection Totally enclose IP 54

        - Cooling Surface cooled with shaft mounted fan, IC 0141

        - Rated voltage xxxV, 3-phases

        - Rated frequency 50 Hz

        - Rated speed 1200, 1800 rpm

        - Insulation Class B, temperature rise B

        - Mounting Foot mounted B3 Flange mounted B5 or as indicated

        - Housing material Cast iron otherwise welded

        - Bearings Ball bearings

        - Accessories Gears (if required)

        Equipment to be provided

        - One(1) lot, AC motor according to motors and components list

         

        Motor control centers

        Switchgear for motor starters and feeders as required for the installed auxiliary AC drive

        equipment and other consumers.

        The AC switchgears will be complete in all respects, pre-assembled and ready for installation

        and connection.

        Included are all indicating equipment, actuators, protection and control equipment.

        Design

        Indoor design, closed cubicles for single or double fronted arrangement, equipped with starter

        comprising all electrical devices such as fused isolator switches, contactor,

        hermal overload protection, motor protection units, individual control voltage transformers and

        relays.

        Cable connection from the bottom.

        - Nominal voltage xxxV, AC

        - Rated frequency 50 Hz

        - Short circuit 15 KA

        - Control voltage 220V, AC

        - Enclosure IP 41

        Equipment to be provided

        One(1) lot, MCC's according to plant requirement incl. incoming feeder panels with load

        break switch.

         

        PROCESS CONTROL SYSTEM

        The purpose of this specification is to define the process control system as required by this line.

        The proposed programmable controllers, microcomputers and standardized stand-alone control systems

        are a reasonable system selection based on the process needs.

        Hardware unification is widely achieved by proper selection and design of the applied systems, thus to minimize

        costs for maintenance and spare parts.

         

        Hardware features

        PLC-systems

        - Marker LG or equivalent

        - Processor 16 bit or 32 bit

        Analog input

        The system scans and converts to digital form, analog signals resenting temperature, pressure,

        flow, lever and other process measurements.

        Five types of module cover the analog requirements of the majority of industrial application,

        - 4 Isolated high-level channels (voltage or current)

        - 4 Isolated low-level channels (thermocouple or low level voltage)

        - 4 Isolated low-level channels (pt 100 probe or low level voltage)

        - 8 Isolated high-level channels (voltage or current)

        - 8 Fast high-level channels (voltage or current)

        Analog output

        Analog outputs for control will have 12-bit resolution D/A converters.

        Output is generally 4-20 mA isolated.

        Digital input

        The system is capable of scanning on sufficient scanning rate every digital input representing

        status information.

        All contacts used as inputs for control functions will be scanned either immediately before

        use or in a manner that ensures updated information.

        Each digital input will be filtered for contact bounce and isolated.

        - Input voltage 110V AC, 24V DC

        Digital output

        Low speed discrete output modules will be potential isolated.

        Status indication is provided.

        Discrete outputs will be suitable for directly energizing and de-energizing motor starter

        magnetic coils or relays and solenoid valve. Each output will be fused and will have status

        indication.

        - Output voltage 220V AC, 24V DC

        Special Input/Output

        For processing of encoder signals, etc. high-speed counter modules will be used.

        Spare capacity

        The control system includes 15 percent built0in spare capacity of used I/O's to allow for

        contingencies and future expansion. This includes I/O, terminations, rack space, memory,

        and programmable function blocks.

        System communication

        Data exchange is, by the use of a digital communication interface between the controller systems.

        Flying master or token passing principle for communication will be applied.

        Subsystem communication

        Data exchange is, by the use of a digital communication interface based on a point-to-point

        connection.

        Alternatively parallel interfacing might be supplied if efficient.

        System Software

        The programmable controller system software will support either relay ladder diagram, functional

        block programming or fill in the blanks, normally open, normally closed, transitional, and latched

        ontacts, timer, counters, 4-function arithmetic, shift register, comparisons, interrupts, closed loop

        control, skip, ASCII reading/writing, subroutines, shall be supported as far as required.

         

        Panels of equipment

        Main panel

        - AC panel (including P.L.C.) Controls AC motors, Solenoid valves and sensors etc.

        - DC panel Controls DC motors.

        Operation panel

        - Entry part

        - Main

        - Flying cutoff machine(DDS)

         

        Line automation function

        Line handling and monitoring

        - Line set-up

        - Line coordination (plant switch on sequence, mode of operation etc.)

        - Alarming

        Line drive master control

        - Speed referencing / control

        - Jogging

        - Running

        - Automatic slow-down

        - Acceleration / deceleration

        - Drive interlocking and sequencing