Rolling Section Mill

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Section and rail rolling Solutions for the efficient production of sections and rails Metals Technologies www.siemens-vai.com

Transcript of Rolling Section Mill

Page 1: Rolling Section Mill

Section and rail rollingSolutions for the efficient production of sections and rails

Metals Technologies

www.siemens-vai.com

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Fast and flexible in the production process

Your challenge:Creating a fast and flexible process is challenging, and fulfilling customers’ orders quickly is key to staying competi-tive. That’s why it’s so important to stay on top of new technologies for each and every step of the production line – from beginning to end. When it comes to the finishing section, you need a seamless workflow with fast, changeable stands and fully automatic stacking and binding systems.

Our solution:Siemens VAI answers these challenges with seamless solutions that address all final processing demands. From fast cutting stands to compact stacking and convenient binding systems, the entire production process is smooth with great-er efficiency. Short cycle times and a flexible machine layout help to process different kinds of steel products with minimal changeover downtime.

Universal stands with the renowned Red Ring designOne of our final processing solutions features builds on our new generation of universal stands, which are based on our renowned Red Ring design. Our new universal stands also include the original features.

Automatic stackers and binding system Our stackers are designed for specific tasks: Our magnetic type is ideally suited for handling medium to large sections, while our combined magnetic-mechani-cal stacker manages small to medium sections. Finally, our completely auto-matic and hydraulically operated binding machine can handle binding bundles in any section.

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Advantages of Siemens VAI universal stands:

� Fast roll changes When rolling structural shapes in the mill, our universal stands can be exchanged with horizontal stands. In addition to the horizontal rolls, they are fitted with a set of idle vertical rolls to work the flange shapes. Our special design means that rolls can be changed in just a quarter of the time it used to take.

� Easy installation Installing universal stands into existing rolling trains requires no significant foundation work, modifications or lengthy downtimes. So for a minimum investment, a wide variety of mills can be quickly and flexibly upgraded.

� Low weight Weighing only half the mass of conventional stands, our universal stands allow the rolls and rolling equipment to be quickly and easily replaced. There’s no need for high-capacity overhead cranes or costly and bulky extraction carriages.

� Remote-control change A remote-controlled roll change robot helps to significantly reduce the roll assemblies’ changeover time.

Advantages of Siemens VAI stackers and binding system:

� Fully automatic stacking Fully automatic operation minimizes personnel costs while increasing on-the-job safety.

� Friction-free product handling Safe binding mechanisms ensure friction-free product handling without surface damage, improving product quality.

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As with our 2-high Red Ring stand, our Red Ring uni-versal stand has no requirement for a standby stock of chocks. Instead, roll changes are performed using a robot system, which mechanizes the assembly/disas-sembly of roll chocks. The process of disengaging a universal stand from the rolling line, such as for stand clamping or spindle holding, is exactly the same as for a normal Red Ring 2-high stand.

Advances with Red Ring 5XX series: � Increased rigidity, for minimal deflections � Possibility of using rolls with a larger diameter,

hence reducing the bite angle � Improved design of chock pivoting system,

for longer bearing lifetime � Best selection of material for tie rods � Optimized manufacturing of chocks

A sophisticated roll systemThe rolls in our system adjust symmetrically around the pass line through a hydraulic motor-driven screw system. For maximum load carrying capability, our system uses 4-row cylindrical bearings with separate thrust bearings. To allow accessibility, hydraulic plungers outside of the tie rods locate roll balance.

In our original version, the conversion 2-high/universal was performed by adding an assembly consisting of chocks and roll gap setting devices of vertical rolls. In our modified version, vertical idle rolls have been added along with chocks and roll gap control devices. Also, for quick assembly and disassembly, the vertical frame is separated from the rods and is locked to the massive rest bar by hydraulic nuts. Both horizontal and vertical rolls are hydraulically adjusted and can be controlled remotely.

Increased life span and cleaner operationThe main bearings and labyrinth seals in all types of Red Ring stands operate with oil/air lubrication instead of automatic grease. That reduces the amount of continuous lubricant that’s needed, and it also lowers bearing operat-ing temperatures. Using oil/air lubrication also increases the life span of the main bearings and labyrinth seals and makes for an overall cleaner operation, especially in the roll change area. Finally, it reduces flume water contamination.

Continuous universal mill at Corus, Scunthorpe, UK Medium-beam rolling

Universal stands quickly reconfigured for maximum flexibility

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Counterbalanced spindle supportThe spindle support, which contains the spindles in a wrapped bearing design, is completely counterbalanced. This feature ensures that hubs remain parallel. It also eliminates hub wobble, and greatly reduces wear. Also, generous tapers on hub entry and roll ends mean that, in most cases, stands can be changed without moving the spindles.

The spindle support and stand are connected by a cross cylinder and pin. The shift cylinder is connected to the spindle support, not the stand. When changing stands, the cross cylinder disconnects the two, and the shift cylin-der retracts the spindle support, which in turn uncouples the service fluids as well as the spindles.

Remote-control change One of the outstanding features of this design is that there’s no need for physical connections between roll spade endings and the spindle hubs. The design allows the stand to be changed via remote control and it signifi-cantly reduces the roll assemblies’ changeover time. We also furnish a roll change robot to aid with the change operation. The unit is normally located in the roll shop and is equipped with a hydraulic power unit.

Features: � Easy conversion to conventional

horizontal stands � 4-row cylindrical bearings with

separate thrust bearings allow maximum load carrying capability

� Fast stand and roll change � Vertical frame separates from the

tie rods for quick assembly � Hydraulically adjusted vertical and

horizontal rolls

Universal stand spindle holder Universal stand on baseplate with spindle holder

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Cooling and precambering systemsIn order for the straightening process to be effective, sec-tions arriving from the cooling area must present a suit-able temperature below approximately 100 °C and correct geometry. For this reason, according to product and lay-out, the cooling bed may be equipped with spray cooling technology. Rails and other special sections may require a prestraightening operation that’s applied at the cooling bed’s entrance. In fact, nonuniform mass distribution in the cross section of the rail tends to bend it inwards on its head side. If not corrected, this would make postcooling straightening very difficult. Rails therefore are precam-bered before being deposited onto the cooling bed and are hydraulically clamped and lifted on the web side. The clamps are mounted on motor-driven cars, each with indi-vidually programmable travel distances that allow for the application of different precamber patterns. Precamber geometries are calculated according to cooling models and rail parameters, which include grade, shape, specific mass, length, and temperature.

Features: � Rails precambered before cooling bed � Rails hydraulically clamped and lifted � Individually programmable travel distances

Straightening systemsStraightening of sections before cutting to final length is necessary to remove the deformations caused by the asymmetrical cooling effects. The sections have to be subjected to a mechanical deformation to reach the yield tensile strength.

Straighteners are composed of a rigid frame containing two staggered rows of double-supported or cantilever-mounted horizontal rollers. The number of rollers varies with the bar size and productivity requirements. The roll-ers of one row are driven by an electrical motor, while the others are idle. The top rollers‘ position is vertically adjust-able according to the bar size, with hydraulic counterbal-ance to eliminate backlashes. Top and bottom rollers are axially adjustable. On either row, the centerline distance of rollers may be fixed or adjustable to accommodate medium and heavy sections, which present a wide range of plastic section moduli.

The rollers are mounted in a removable cassette. For a quick changing operation, the cassette is automatically removed and replaced with another cassette that‘s ready with standby rollers.

For an effective straightening process, the sections are kept in order and firmly guided with special combing devices or pinch rolls that ensure bar separation. Magnetic rollers at the straightener‘s exit prevent bars from slipping during travel to the dividing shear.

Straightening rollers are independently adjustable at both sides.

9-roller straightener with removable cassette

Effective cooling and straightening

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A suction system removes the scale peeling off the bars during straightening.

Other types of straightening systems are designed for rail and special sections processing.

Features: � Rigid frame contains two sets of

double-supported horizontal rollers � Top rollers’ position is vertically

adjusted according to bar size � Hydraulic counterbalance eliminates

vertical movement backlashes � Axial adjustments for rollers � Rollers mounted in removable cassette

for quick changing operation � Special combing devices or pinch rolls ensure

bar separation for effective straightening process

� Magnetic rollers at straightener’s exit prevent bars slipping

� Suction system removes scale during straightening

Straightening rollers are independently adjustable at both sides.

Rail precambering system

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The layers of sections arriving from the straightening and cold-cutting area are properly braked and buffered onto the first transfer table of the stacking area.

Aligning rolls and stoppers gives bars an orderly disposition. Should there be out-of-tolerance bars or emergency conditions, a special system directs bars to separate cradles.

Individual layers with the desired number of bars are formed and separated by using disappearing stoppers and variable-speed devices.

According to the section shape and size requirements, the appropriate sequence of straight and 180-degree rotated layers will be sent to the stacking device. The synchronized operation of suitable devices with mechanic or hydraulic drives provides the necessary movements of lift, travel and rotation. Devices are equipped with electromagnets to provide a firm grip on the bars, and special equipment to release them when demagnetized.

The stack is formed on a lowering cradle, where layers are deposited with the correct sequence of straight and rotated sections until the desired stack is completed. The stack dimensions are calculated as a function of weight, section type and size, and stability requirements.

Combined magnetic-mechanical stacker

Stacking systems for all section sizes

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An adjustable-width roller table transfers the stacks to the binding area. The roller table is equipped with horizontal and vertical rollers in order to maintain a good stack alignment during travel.

Tying or strapping machines provide the binding to meet customer’s processed weight requirements.

After applying the preset number of bindings, the stacks are weighed, labeled, and dispatched to the storage area. All operations are fully automatic and computer-controlled.

The stacking area is designed to give bars enough resi-dence time in order to provide flexibility and accumulation capability with respect to the rolling mill.

Stacking systems have a divisible design that provides the flexibility needed to process different stacks of different lengths. This feature significantly increases the productivity rate for stacks with shorter lengths.

For the most part, a fully magnetic stacker is used for medium to large sections. For processing small to medium sections, a combined mechanical-magnetic type is pre-ferred, which avoids the residual magnetization effect on light bars, preventing misalignment and an incorrect stack formation.

Working sequences of stacking and binding are fully automated and integrated with the other areas of the rolling mill.

Features: � Special system directs out-of-tolerance bars

to separate cradles � Disappearing stoppers and variable-speed devices

form and separate individual layers � Synchronized operation of suitable devices

ensures correct sequence of straight and 180-degree rotated layers

� Electromagnets equip devices for firm grip on bar � Adjustable-width roller table transfers stacks

to binding area � Horizontal and vertical rollers maintain good stack

alignment in transit � Operations all fully automatic and computer-controlled � Divisible design provides flexibility needed to process

different stacks of different lengths for greater productivity

� Combined mechanical-magnetic type processes small to medium sections

� Working sequences of stacking and binding fully automated and interfaced with the other areas of the rolling mill

Magnetic stacker Straight and rotated layers for stack stability

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For hot-cutting rails to finished lengths and medium-large sections, sawing may be preferred over shearing equipment for several reasons. Sawing can eliminate the deformation of bar ends and obtain better cut quality and precision. Depending on the application, process parameters, and operational requirements, hot-sawing processes with either metallic or abrasive disc technologies can be used. According to the application, the requirements of postprocessing operations such as burr removal and edge trimming are eliminated or significantly relieved.

During cutting, the bar is firmly clamped at both sides of the wheel. Depending on the dimension and shape of the bars to be cut, the wheel approaching and receding movements can be either pendulum or linear type.

The saw is also used for nose and tail cropping, with an automatic crop discharge system. Bar samples can also be cut with a special conveyor to remove them.

Cut swarf is collected in a bin at the saw, while a separate dust removal and filtering system is provided.

An automatic system compensates for the wheel wear and helps to minimize the process cycle time.

Features: � Metallic or abrasive disc technologies available � Pendulum or linear disc movement � Automatic removal of nose and tail crops � Collection of sawing swarf � Dust removal and filtering system � Fully automated sawing procedures

Metallic disc sawAbrasive disc saw for rails

Sawing units

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Excellence derived from experienceSelected success stories with Siemens VAI section & rail rolling

Expandingbusinessopportunities

Customer: ArcelorMittal Temirtau, Temirtau, Kazakhstan

Planttype: Bar and section mill

Oursolution: A continuous mill with 16 horizontal, vertical and convertible Red Ring stands

Technicaldata: 400,000 tpy

The result: Flexibility for a large range of sections

World’sfirst120-min-linecontinuousfinishingmill

Customer: Corus Scunthorpe (TATA), Scunthorpe, United Kingdom

Planttype: Section and rail mill

Oursolution: Seven universal/horizontal Red Ring stands, plus eleven standby units

Technicaldata: 570,000 tpy (sections), 200,000 tpy (rails)

The result: New engineering solutions for easy stand conversion and replacement; continuously rolled rails up to 120 m length

Largeproduction

Customer: SAIL Steel Authority of India Limited, Durgapur, India

Planttype: Bar and section mill

Oursolution: A continuous universal rolling mill with 16 Red Ring stands

Technicaldata: 1,000,000 tpy of sections up to 300 mm

The result: Maximum flexibility for one of the largest capacity rates

Stainlessquality

Customer: Viraj Profiles, Mumbai, India

Planttype: Bar and section mill for stainless steel

Oursolution: A Red Ring sliding rougher followed by a continuous rolling mill with 18 Red Ring stands

Technicaldata: 180,000 tpy of sections up to 300 mm

The result: Top-class installation for stainless market

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CompetenceCenter:Siemens Industry Inc. 15 Belmont Street Worcester, MA 01605-2665, USA Phone: +1 508 755-6111Fax: +1 508 832-0139E-mail: [email protected]

Siemens VAI Metals Technologies S.r.l. Via L. Pomini, n. 92 21050 Marnate (VA), Italy Phone: +39 0331 741211Fax: +39 0331 741386

Headquarters:Siemens VAI Metals Technologies GmbHP.O. Box 4, Turmstr. 44 4031 Linz, AustriaPhone: +43 732 6592-0Fax: +43 732 6980-0E-mail: [email protected]

www.siemens-vai.com

Order No. E10001-M4-A117-V1-7600 Dispo No.: 21661 K-No.: 28104 | Printed in Germany GB 110083 WS 06111.5 | © 06.2011, Siemens AG

All rights reserved. Subject to change without prior notice.

The information provided in this brochure contains merely general descriptions or characteristics of performance which in actual case of use do not always apply as described or which may change as a result of further development of the products. An obligation to provide the respective characteristics shall only exist if expressly agreed in the terms of contract.