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ULTRASONIC and HIGH-PRESSURE STRIP CLEANING TECHNOLOGY METALLURGICAL PLANTS and ROLLING MILLS STRIP PROCESSING Technical Report Hot and Cold Strip Processing Dr. M. Kretschmer ULTRASONIC and HIGH-PRESSURE STRIP CLEANING TECHNOLOGY

ULTRASONIC and HIGH-PRESSURE STRIP CLEANING TECHNOLOGY · ULTRASONIC CLEANING The ultrasonic cleaning combines the cleaning of the surface by active processes on the surface (lipids

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Page 1: ULTRASONIC and HIGH-PRESSURE STRIP CLEANING TECHNOLOGY · ULTRASONIC CLEANING The ultrasonic cleaning combines the cleaning of the surface by active processes on the surface (lipids

ULTRASONIC and HIGH-PRESSURESTRIP CLEANING TECHNOLOGY

METALLURGICAL PLANTS and ROLLING MILLS

STRIP PROCESSING

Technical ReportHot and Cold Strip ProcessingDr. M. Kretschmer

ULTRASONIC and HIGH-PRESSURESTRIP CLEANING TECHNOLOGY

Page 2: ULTRASONIC and HIGH-PRESSURE STRIP CLEANING TECHNOLOGY · ULTRASONIC CLEANING The ultrasonic cleaning combines the cleaning of the surface by active processes on the surface (lipids

Strip processingSMS DEMAG

INTRODUCTION

Essential customer demands for refined sheet products are good machineability in secondary manufacturing process and long term preservation ofthe final product. These qualities are fundamentallydetermined by the functional layer applied to themetal surface. The compound between the functio-nal layer, e. g. the zinc layer, and the steel strip sur-face is primarily based on the adhesive strengths within the boundary surface. Deposits on the sur-face, such as abraded iron particles, oil or rollingemulsion remains, disparage the adhesion. The functional layer is not able to adequately fulfil thepurpose. It is only irregularly applied or is easilyremoved under mechanical pressure.

In order to peel off the disturbing adhesions from the steel strip surface before it enters the refiningprocess, the strip comes into intensive contact withthe alkaline cleansing agents in the cleaning section.The strip refining of a hot-dip galvanizing line is usually composed with a combination of various alkaline cleaning processes and a concludingaqueous rinsing.

2

STATE OF CLEANING

TECHNOLOGIES AT SMS DEMAG

Hot-dip galvanizing lines use cold rolled steel strip asmaterial. Cold rolled strips are burdened with rolling emulsion and rolling residues resulting fromthe rolling process. Deposits of about 500 mg/m2

per side, consisting of rolling emulsions, abraded iron particles and other dirt are therefore likely. Steel strip burdened in this way has to be relieved of these residues resulting from the cold rolled process before it enters into further surface refining.In accordance with state of the art technology thisprocedure is executed in a multi-stage strip cleaningsection. A combination of an alkaline spray cleaningwith brush support for the removal of surface depo-sits, an electrolytic cleaning for deep pore cleaningand a final multi-stage rinsing with fully deminerali-sed water is used in this section. Cleansing agentsare aqueous solutions based upon alkali, tensidesand phosphates.

Installations for strip cleaning of SMS Demag distinguish itself by the optimal symbiosis of highrefining performances and economical use of resources. The construction design of the machineryguarantees the maximization of the whole refiningperformance. The coordination and application offluid streams secures to minimise fluid and energyconsumption.

The pre-cleaning section has vertical spray degrea-sing and a vertical electrolytic degreasing on its exitend. SMS Demag effectively achieves a long treat-ment line with but actually with a short length facilityby this method of construction. Thereby, good refi-ning results are attained and the building will not beunnecessarily long.

Special sealing systems at the roller breakouts in theform of labyrinth seals with collection troughs andreturn flows to the tank minimize the free outlet shapes for gases, fumes and fluids. The quantity of sealdrains is minimized by well-aimed suck-off in

ULTRASONIC and HIGH-PRESSURESTRIP CLEANING TECHNOLOGYULTRASONIC and HIGH-PRESSURESTRIP CLEANING TECHNOLOGY

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3

the region of the free outlet areas that leads to energy savings. Tank covers are sealed by a waterseal so that a suction of separate air can be avoided.The tank covers are carried out in form of a roof toprevent the drain of condensate.

The partition walls of the process tanks are equippedwith “u”-shaped collecting troughs to avoid forma-tion of drops. The transitions of tanks are fitted withspecial systems for the prevention of fluid and steamloss.

The high mechanical cleaning effect in the spray sections is caused by the nozzle characteristic (nozzle arrangement on the pipe, spray angle, bigspray drilling and by that optimal energy use of thespray radiation). The well-balanced pressurization ofthe medium onto the strip is enabled by the optimalselection of the nozzle characteristic. Nozzle pipeswithout blockage are guaranteed by the use of tongue nozzles. The nozzle pipes are laterally exten-dible and can be exchanged during operation. Theapplied setting secures that the adjusted spray angleis retained after the changing. A maintenance-lowoperation with slight energy losses is the net effect.A well-balanced pressurization of the medium ontothe strip arises by the pressure distribution. Herewitha high mechanical cleaning result and a low evapora-tion of the fluid are combined. Consequently theaerosol losses are minimized.

The brushing machines distinguish themselves bytheir robust construction and running smoothness.Material damages and traces on the strips are thereby prevented. Furthermore a long service life of the brushes with a low spare parts consumptionand maintenance expenses are a result. The basicadvantage of the brushing is the construction of thebrushing power system. The power is applied on thebrushing roll neck by bellow cylinders which centrallyput the load onto the bearings of the brushing rolls.This design prevents the bending of the brushingrolls and guarantees the calm operation of the brushing machines. The wear of bearings is reducedand chatter marks are avoided. The bearings of brus-hes and rolls are sealed. Short changing times(approx. 30 min per roll) for brushing roll and counterroll contribute to the easy maintenance.

The electrolytic degreasing has an excellent cleaningperformance by the use of high current density andan optimal electrolyte guide way. The flow path ofthe mediums from downwards to upwards throughthe process tank supports the degasing of the produ-ced hydrogen, avoids formation of gas nests in theprocess tank and minimizes the foam production.The construction and performance of the electrodesrealize minimal electric resistance loss. The optimizeddegasing and minimized foam production facilitate tooperate the electrolytic cleaning with high currentdensities up to 20 A/dm2. The vertical strip flowensures a stable, defined position of the strip bet-ween the electrodes without sagging.

The cascade guiding of the cleaning medium in thestrip cleaning installation guarantees a continual, highcleaning quality. Special equipments for the fluidmaintenance, especially the suitable installation ofmagnetic chain filters, ensuring the maximum effi-ciency of the strip cleaning.

The rinsings are arranged in cascades and combine a modest waste water amount and fresh water consumption with an excellent flushing effect at thesame time. The last rinsing cascade is operated withtotally demineralised water. The process tank isequipped with tongue nozzles in the spraying headerand runs with a process pressure of 10 bar in the lastrinsing cascade to achieve a high rinsing effect.

The combination of strip edge blow-off and stripdryer after ending the strip cleaning guarantees acomplete and over the whole strip width homogene-ous and cost efficient drying of the strip surface toend the spreading of fluids.

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SMS DEMAG INNOVATIONS

IN THE CLEANING TECHNOLOGIES

The potential for innovations in the conventional cleaning technologies lay in the reduction of theenergy requirements, the minimized chemical useand the lower expenses for wearing parts, e. g. bythe renunciation of the brushes.

Feature 1: Pilot plant for strips in the Dortmunder Oberflächen-Centrum

4

Due to continual contacts to the user and based ondata and experiences from running production lines a permanent development of our technology takesplace. Moreover SMS Demag is in the position toindependently optimize existing process technologiesand applications of new products at our Technikumplant.

Strip processingSMS DEMAG

On the top of this SMS Demag is partner for theDortmunder Oberflächen-Centrum (DOC), keeps anexperimental plant for testing forward-looking proces-sing methods and new processes (feature 1). Owingto these opportunities SMS Demag has the ability tooffer the optimal process for each plant design.

It is known from the cleaning of individual parts thatby increasing the mechanical energy influence ontothe surface in question, e.g. in the ultrasonic andhigh pressure processes, an essential improvementin cleaning effects can be achieved. By using theultrasonic and high pressure cleaning a clearly lowerecological damage can be expected. The quantitiesof waste water in the production process „surfacerefining of steel strips“ are noticeably reduced by theperceptible lower requirement for cleaning agentsand the optimizing of the circulatory guidance of thestrips in combination with the possible use of thediaphragm technology for additional fluid conditio-ning. Positive knowledge regarding the adaptation ofthe ultrasonic und high pressure process at the pilotplant for strips in the Dortmunder Oberflächen-Centrum (DOC) is on hand.

Page 5: ULTRASONIC and HIGH-PRESSURE STRIP CLEANING TECHNOLOGY · ULTRASONIC CLEANING The ultrasonic cleaning combines the cleaning of the surface by active processes on the surface (lipids

The central component in the high pressure cleaningis the relevant pump. A Pitot pipe pump is chosenfor high pressure pump package (Feature 3). Alreadythis kind of pump is successfully used for the cleaning of different steel strips in the pilot plant forstrips in the Dortmunder Oberflächen-Centre. Themode of operation of the pump is discernible in thebasic plan. The medium enters the pump chambervia the suction socket. In contrast to customary centrifugal pumps the pump chamber at this pump isthe rotor. In the rotating pump chamber the mediumis brought on a very high rotary velocity. In the rota-ting fluid body is the fixed Pitot pipe. In this pipe the(kinetic) rotary energy of the medium is transformedinto (potential) pressure energy. The high rotary velo-city of the medium causes a fluid pressure above100 bar at the pressure socket.

5

TECHNOLOGY OF

HIGH PRESSURE CLEANING

The high pressure cleaning connects the cleaning ofsurfaces by active surfaces processes (lipids in thestrip cleaning medium) with the mechanical removalby the kinetic energy of the fluid stream. The hotfluid stream bounces against the strip surfaces withhigh velocity. Loose surface layers get rinsed. Morestabile layers get broken up and also rinsed by thekinetic energy of the bouncing fluid. The lipid parts inthe additive strip cleaner partly support the refiningprocess. The essential function of the lipids is thebond of removed disposals in the fluid. The removedfilm is bonded within the fluid phase and does notget in contact with the strip surface again. This prevents a regreasing/recontamination. Without thelipids the oily parts of the removed disposals swimon the fluid (drops, jet, full streaming etc.) becauseof their less density und nonpolar structure and aregiven off with another contact with the surface.

Feature 2: High pressure and ultrasonic cleaning in the pilot plant for strips in the Dortmunder Oberflächen-Centrum (DOC)

ultrasonic cleaning high pressuremodule

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6

The cost efficient use of the high pressure cleaningrequires the circulation of the cleaning mediumthrough the high pressure pump. The cleaning mediais a multiple phasing fluid, consisting of a fluid phaseof the cleaner and included gas or foam bubbles. The foam formation in the medium can not be totallyexcluded with the use of an alkaline, tenside-contai-ning cleaner. In centrifugal or reciprocating pistonpumps even small gas parts in the medium lead tocavitation appearances in the pump chamber andwith that to the breakdown of the pump within a

Feature 3: Function principle of the Pitot pipe high pressure pump

short time. A Pitot pipe pump has been selected due to its relatively high insensitivity against gas/foam(gas part < 10 Vol. %) in the pumping fluid. In resultof the spread of pressure the gas parts collect them-selves in the centre inside the fluid body where theydo not get in contact with the changed pressure con-ditions in the outside standing Pitot pipe. In the pumproom a fast rotating fluid ring with a gas bubble in itscentre of rotation is formed. The additional separatedrinsing of the flinger seal reduces the wear by particles in the medium.

Strip processingSMS DEMAG

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TECHNOLOGY OF THE

ULTRASONIC CLEANING

The ultrasonic cleaning combines the cleaning of thesurface by active processes on the surface (lipids inthe strip cleaning medium) with the mechanicalremoval by kinetic energy of imploding gas bubbles.The ultrasonic oscillations lead to local pressure fluc-tuation in the fluid. In sections where the pressuregoes below the gas pressure of the released gas orthe steam pressure of the fluid, tiny cavitation bub-bles develop. The bubbles rapidly implode becausethe artificial conditions which lead to the forming ofbubbles only exist for a short time. The shock waveswhich are induced by the implosion of the gas bub-bles (especially on the strip surface) blast away thedirt on the surface. Surface layers which are loosebecome removed. More stabile layers are broken upby shock waves and also washed away. The lipidparts in the added strip cleaner partly support the cleaning process. The main function of the lipids isthe binding of the removed dirtying in the fluid.

Cleaning with ultrasonics has the big advantage thatbeneath the high quality and reproducibility of thecleaning results materials can be cleaned mechani-cally but without any contact. Depending on the cleaning requirement you can therefore abstain fromaggressive chemicals and high temperatures. Thechemical additives (cleaning agents) which supportthe aqueous ultrasonic cleaning are added in a lowpercentage and are similarly important in the choicetowards the required ultrasonic performance and theworking frequency. Depending on the field of applica-tion the ultrasonic cleaning produces a high-qualityand homogeneous cleaning result that can not beachieved by any other cleaning process.

The ultrasonic oscillation technology used requiresno special bath conditioning. The vibrators are capsu-led in a stainless housing. The housing material canbe suited to the bath medium. The process tank isexecuted as a sink tank to have enough medium atits disposal to transmit the sound waves onto thestrip surface. Only a moderate flow rate has to beadjusted in the sink tank so that the bubbles formeddo not flow away immediately and / or to hinder thesound waves in their propagation.

EFFICIENCY OF THE HIGH

PRESSURE AND ULTRASONIC

CLEANING TECHNOLOGY

Efficiency and quality of the high pressure and ultrasonic cleaning technology has been examined in different tests at the pilot plant for strips of the DOCand at the hot-dip galvanizing line of Thyssen KruppStahl AG in Bochum. The technological cleaning inthe pilot plant for strips of the DOC essentially con-sists of a pair of high pressure spraying headers andan ultrasonic cleaning tank. Detailed tests have con-firmed that the cleaning efficiency for different kindsof steel strip is improved over the conventional stripcleaning section. Tests in the hot-dip galvanizing line of Thyssen Krupp Stahl AG in Bochum have confirmed this potential under industrial conditions.These results will be exemplary discussed twice inthe following, a cold rolled multi-phase steel strip and an electrolytic tinned steel strip.

The degree of cleaning for rolling emulsion and ironabrasion was separately analyzed and presented.Feature 4 shows the degree of cleaning of the highpressure and ultrasonics in relation with the rollingemulsion plate as a function of the strip speeddepending on the method of plant processing.Feature 5 demonstrates the degree of cleaning ofhigh pressure and ultrasonic cleaning in relation withiron layer as a function of the strip speed dependingon the way of plant processing. A duplex-grain steel,a so called high-strength multi-phase steel, was usedas substratum. This kind of steel is hard to clean onoccasions.

The degree of cleaning falls down with the increa-sing strip speed. Higher quantities of dirtying appliedvia the strip surface can only be removed partly. Thecleaning technologies used have different influenceson the respective cleaning results. The high pressurecleaning alone removes 80 % of the rolling emulsionlayer at minimum. The iron pollution alone can bereduced by 92 % at the minimum by this technology.

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Strip processingSMS DEMAG

Feature 4: Cleaning efficiency of high pressure and ultrasonic cleaningreferring to rolling emulsion dirtying

Deg

ree

of

clea

nin

g

Strip speed (m/min)

High-pressure cleaning

High-pressure and ultrasonic cleaning

Strip DP - K34 / 60; 250 x 0.6 mm, 290 mgOl/mHigh-pressure, tensid cleaning agentUltrasonic, tensid cleaning agent

Feature 5: Degree of cleaning of high pressure and ultrasonic cleaning regarding dirtying with rolling abrasion / Iron Fines

Deg

ree

of

clea

nin

g

Strip speed (m/min)

High-pressure cleaning

High-pressure andultrasonic cleaning

Strip DP - K34 / 60; 250 x 0.6 mm, 330 mgFe/mHigh-pressure, tensid cleaning agentUltrasonic, tensid cleaning agent

The ultrasonic cleaning as fine cleaning has itsstrength in reducing the burden of rolling emulsion.The cavitation of the bubbles produced on the sur-face blows up and removes tiny emulsion remainsout of the technical surfaces. The additional cleaning

effect by the parallel use of the ultrasonic and thehigh pressure cleaning is lower for the larger iron particles which mainly lay on the strip surface because of their size.

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showed that the effectiveness of the process abovea minimum limit is mostly independent to the com-position of the bath. For the case of electrolytic-galvanized strip surface the degree of cleaning increases with the increased concentration of theadditives in the ultrasonic cleaning. If cleaning-activetensides in a separate quantity, which is above thecleaning concentration added on top, the cleaningefficiency increases further. The best cleaning degreecan be achieved by using a combination of high-pressure and ultrasonic cleaning. The start of the first cleaning step causes another increase of the cleaning efficiency by approx. 5 to 10 %.

The following investigations were carried out on galvanized sheet with a corrosion protective oil layer.Both cleaning sections were operated with a tensidecleaning agent. Feature 6 shows the possible clea-ning grades independent of strip speed, cleaningconcentration and operating practice of the strip cleaning sections. By increasing the strip speed thegrade of cleaning decreases. By means of the stripsurface larger contaminants are taken into considera-tion which consequently leads to the decreasingexposition time and can only be partly removed. It becomes obvious that also the cleaning agent concentration has influence on the efficiency of theprocesses. The investigations with annealed strip

Feature 6: Cleaning degree of high-pressure and ultrasonic cleaning with regard to corrosion protection oil layers

Deg

ree

of

clea

nin

g

Strip speed (m/min)

Ultrasonic cleaning (low quantity of cleaning agent)Ultrasonic cleaning (medium quantity of cleaning agent)Ultrasonic cleaning (low quantity of cleaning agent plus tensides)High-pressure and ultrasonic cleaning

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The efficiency of the high-pressure cleaning techno-logy was confirmed significantly in our first industrialapplication. The existing strip cleaning installation ofthe hot-dip galvanizing line at Thyssen Krupp StahlAG was equipped with a high-pressure module. Thehigh-pressure module was operated with cold indu-

strial water without addition of cleaning media. Onlythe kinetic energy of the high-pressure water blastswas sufficient enough to result in a significant impro-vement of the cleaning efficiency (Feature 7). At thesame time a proof could be found for the fact thatthe increase of work pressure does not necessarily

Strip processingSMS DEMAG

Feature 7: Cleaning efficiency of the high-pressure cleaning module in a hot-dip galvanizing line

High-pressure

cleaning module

100 bar

High-pressure

cleaning module

80 bar

High-pressure

cleaning module

120 bar

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11

imply the improvement of the cleaning result. Theincrease of jet pressure from 80 bar to 100 barimplies a provable improvement of the cleaning quali-ty. But a further raise of the pump power from 100bar to 120 bar has negative implications. The result isan intensified streaking on the strip surface becausethe water jets start overlapping further and precludetheir cleaning performance. The working pressure ofthe high-pressure module can be adapted by thedesign of the spraying header and the choice ofspraying systems optimal to the environmental conditions.

LINE CONCEPT

In the first part of the strip cleaning section (feature8) the strip is processed to the necessary tempera-ture and the surface soils are cleaned away by thehot alkali cleaning solvent. In the spray degreasingsection the strip is sprayed upon intensively with the hot cleaning media in order to heat it up to therequested temperature level and to remove coarse,adhesive contamination. The brush degreasing remo-ves contamination on the strip surface by means ofseveral rotating brushing units. The electrolyticdegreasing removes contamination by means ofdirect blistering on the strip surface which are dee-

per in the topography. The following brush rinsebrushes off tiny remaining contaminations from thestrip surface. Then the strip surface is rinsed withhot demineralised water in order to wash away thecleaning solvent completely.

With good frame conditions cleaning degrees up toapprox. 90 % can be achieved in the relevant stripcleaning sections. This means the initial contamina-tion of the steel strip are reduced down to approx.10 %. In the area of brushing aggregate and theelectrolytic degreasing there is some optimizingrequirement. The mechanical contact of the bristlesand the strip surface results in a wear of the brusheswhich is related to future continuous costs. Theremoval process with the high-energetic water hea-ders in the high-pressure cleaning does not imply adirect mechanical contact and is therefore complete-ly wear free. The electro-chemical process in theelectrolytic degreasing requires a costly design of theprocess containers. In addition the production of oxygen and hydrogen gas in the process impliesanother safety risk. With the omission of the electro-chemical reaction in the ultrasonic cleaning thedesign of the process container is much simpler. The emission free, mechanical removal process isnot subject to special requirements for the containerexhaust and is therefore with regard to safety uncritical.

Feature 8: High-performance strip cleaning section SMS DEMAG(Conventional Design)

Jet degreasing

Brush degreasing

Electrolytic degreasing

Brush rinse

Cascade rinsing

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Strip processingSMS DEMAG

12

In different tests the efficiency of the high-pressureand ultrasonic cleaning technology has been exami-ned. Because of these examinations it has beenpossible to find out that the technically soiled (contaminated) steel strips can be cleaned with avery good result via high-pressure and ultrasonic cleaning. The high-pressure cleaning provides a good coarse cleaning. The kinetic energy of the high-pressure jet of water works on the surface coatings, causes cover layers to be removed.Contamination which is deeper in the topography of the technical surface are loosened by the ultra-sonic cleaning and cleared away. The formation and implosion of tiny gas bubbles on the strip surface which is due to the ultrasonic vibration blasts adhesive coverings off.

Based on these test results the following cleaningconcept was developed and focused upon (feature

9). The arrangement of the strip cleaning sectionstays in general the same, but expanded by a high-pressure and ultrasonic cleaning section. The brushdegreasing and the brush rinsing are being substitu-ted by a pair of high-pressure spray headers each.The electrolytic degreasing section becomes a ultra-sonic cleaning section by means of exchange of theelectrode systems by respective ultrasonic systems.

High-pressure cleaning technology, as an alternativesolution, eliminates the costly use and maintenanceof brushes.

Ultrasonic cleaning in parallel to electrolytic cleaninguses less energy to achieve the good cleaningresults. The compact design of the process techno-logies opens new opportunities for the constructionand design of space-saving high-pressure cleaningsystems in strip processing lines.

Feature 9: High-performance strip cleaning section SMS DEMAGwith high-pressure and ultrasonic cleaning modules

Spray degreasingwith HP-Modul

Ultrasonicdegreasing

Rinsewith HP-Modul

Cascade rinse

High-pressure cleaning

Ultrasonic cleaning

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Feature 10: Customer profit and saving potential of SMS Demag strip cleaning technologies

OUTLOOK

The results of our investigations have shown thathigh-pressure and ultrasonic systems can be equip-ped for the cleaning of steel strip before the surfacerefinement process with good success. The task ofthe research projects, to minimize environmental pollution, resulted in improvement to the product and a reduction in production costs, giving majorbenefit.

With the use of the high-pressure cleaning technolo-gy as substitution for the mechanical brush cleaning,operational costs for spare brushes are abandonedwhich as wear parts have to be replaced regularly. The ultrasonic cleaning as parallel to the electrolyticcleaning consumes far less energy to reach the

required cleaning result. The compact design of theprocess technology opens news opportunities for thedesign and construction of space-saving strip cleaning sections in strip processing lines (feature 10).

Additionally it was shown that due to the increasedefficiency of the strip cleaning with the innovativeand new cleaning process relevant savings withregard to the amount of cleaning chemicals can beachieved. The environmentally important compo-nents (tensides, phosphates, etc.) in the cleaningagent itself can be significantly reduced. The cleaningof the waste water can be operated at lower costand energy use.

Conventional Design

Material-Manufacturing 100%Engineering 100%Erection 100%

SMS Demag Design

Material-Manufacturing 87%Engineering 91%Erection 78%

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Strip processingSMS DEMAG

14

SUMMARY

Expansion of the spray degreasing by a high-pressure module

Last spray header as high spray header

Omission of brush cleaning => wear free surface cleaning

Substitution of electrolytic cleaning by ultrasonic cleaning

Significant reduction of energy requirement

Easier container design

No extensive safety technique and exhaust

High-pressure module as last cleaning step despite of brush cleaning

Omission of brush cleaning => wear free surface cleaning

Customer profits

No abrasive cleaning procedure necessary anymore

Shortening of line length by approx. 25%

Approx. 10% less investment costs

Less energy expenditure due to omission of electrolytic cleaning

Usage of the existing media cycles

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Page 16: ULTRASONIC and HIGH-PRESSURE STRIP CLEANING TECHNOLOGY · ULTRASONIC CLEANING The ultrasonic cleaning combines the cleaning of the surface by active processes on the surface (lipids

SMS DEMAG AG

Strip Processing Lines Division

Walder Strasse 51-5340724 Hilden . Germany

Phone: +49 (0) 211 881- 5911Telefax: +49 (0) 211 881- 4212

E-mail: [email protected]: www.sms-demag.com

MEETING your EXPECTATIONS

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