Tag Archives: structural steel

Structural Steel FAQ, Part 5 – Assessing Surface Profile

Besides the degree of cleanliness – the removal of oil and grease, rust and mill scale, dust, and other contaminants – surface preparation specifications must also consider the surface profile and roughness relative to the coating to be applied.  Rosler Metal Finishing builds shot blasting equipment to create the right surface profile on structural steel components as well as cleaning them in preparation for coating and painting.

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Painted steel exiting a preservation line

This installment of our Structural Steel FAQ series will answer What is the optimum the surface profile for a structural steel component prior to painting and how is profile evaluated?

Optimizing for Painting

Shot blasting makes a surface rougher to increase the total contact area between paint and a work piece substrate and generally improves paint adhesion. A surface that is too smooth poses the risk of inadequate paint adhesion, while a surface that is too rough may not cover the peaks. The degree of surface profile required depends entirely on the coating to be applied.

Continue reading Structural Steel FAQ, Part 5 – Assessing Surface Profile

Structural Steel FAQ, Part 4 – Evaluating the Presence of Dust

As an expert in the surface finishing industry, Rosler Metal Finishing knows that all the expertise in the world won’t do any good if the surface of the work piece is not properly prepared. When it comes to structural steel, we receive many frequently asked questions about preparation. This installment of our Structural Steel FAQ series will answer How is the presence of dust on shot blasted structural steel components evaluated?

The Dangers of Dust

Blast-cleaned structural steel surfaces must be completely free of dust to ensure proper coating and painting.sgfdfsdfgdf

Residual dust will reduce the adhesion of subsequently applied coatings and, by absorbing moisture, may promote the corrosion of the blast‐cleaned steel surfaces. The potential accumulation of dust is especially critical on horizontal surfaces, the interior of pipes, and in structural cavities.

Special inspections must be carried out to ensure that such areas are adequately cleaned and free from dust before painting.

Continue reading Structural Steel FAQ, Part 4 – Evaluating the Presence of Dust

Structural Steel FAQ, Part 3 – Evaluating Rust and Mill Scale Pre- and Post-Blast

Surface preparation can account for up to 40 percent of structural steel painting and repainting jobs. As Rosler Metal Finishing’s Structural Steel FAQ series has already established, the life of anti‐corrosion coatings on a steel surface depends to a large extent

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Application of anti-corrosion paint in a preservation line blasting system.

on how thoroughly this surface has been prepared for painting.

Properly evaluating the surface of structural steel surfaces for coating before and after shot blasting will help balance the cost of preparing, repairing, and monitoring structural steel throughout its impressive lifespan.

This installment of our Structural Steel FAQ series will answer How are rust and mill scale evaluated pre and postblast?

The Standards

Widely used standards were developed to visually assess the initial surface conditions and the quality of the required surface preparation relative to the initial steel surface conditions.

The dominant standards for evaluating rust and mill scale are ISO 8501‐1:2007 (based on the Swedish standard SIS 05 59 00), SSPC Vis 1‐89, and NACE. While different in some minor details, these standards are practically identical.

Continue reading Structural Steel FAQ, Part 3 – Evaluating Rust and Mill Scale Pre- and Post-Blast

Structural Steel FAQ, Part 2 – Methods of Surface Preparation

Structural steel is a widely used material in a variety of industries due to its strength and durability. Our last post in the Structural Steel FAQ series established why this material must be prepared – namely to preserve its strength and longevity. This post will describe the type of surface preparation required before shot blasting structural steel.shipbuilding2938x450

In order to stand up to the harsh demands of the construction, shipbuilding, and heavy equipment industries, the most appropriate type of surface preparation must be undertaken to ensure the best shot blasting results possible.

As always, consult a surface finishing expert such as Rosler Metal Finishing with to discuss your specific components, their condition, and the desired outcome for your structural steel applications.

We turn to another FAQ about structural steel: What type of surface preparation is required prior to shot blasting?

The answer depends on the condition of the component…

Read more about structural steel surface preperation

Structural Steel FAQ, Part 1 – Why Surface Preparation is Necessary

Structural steel components are used in many industries, including construction, shipbuilding, and the production of all kinds of heavy duty vehicles, trucks, railway vehicles, agricultural implements or construction equipment. From the construction of bridges, building of ships or production of equipment that must withstand heavy loads, steel is selected for its strength and durability.

To live up to its full potential and prevent premature failure, the steel must be guarded against corrosion with a protective coating. Shot blasting plays an indispensable role in preparing the steel surface for such coatings. Partnering with a shot blasting expert such as Rosler Metal Finishing can help you determine the shot blasting equipment, blast media, and process required for your structural steel components.

In a series of blog posts, we’ll answer the most common questions about the surface preparation and coating of structural steel.

We begin with a basic question: Why do structural steel components need to be prepared for protective paint coating?

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Rosler Offers Unique Solutions – Record-setting Preservation Line Used for Shipbuilding

“Finding a Better Way” isn’t just a tagline at Rosler Metal Finishing; it’s a mission. A recent preservation line developed by Rosler Germany is no exception.

The creation of a 740-foot-long (225 meters) shot blasting line with straightening equipment is the largest equipment project Rosler Germany has ever undertaken. Commissioned by Meyer Shipyard in Turku, Finland, the state-of-the-art equipment will be used to prepare and finish materials for building cruise ships.

Read more about this record setting preservation line

Clean Fabricated Constructions with Shot Blasting Solutions

Shot blasting machines come in all shapes and sizes. Selecting a machine capable of cleaning and descaling complex fabricated components and welded constructions is not a task to pursue alone. Seeking the help of a company with proven expertise in the shot blasting field is always advised.

Designed specifically to clean wide head and base plates, ribs, re-enforcements, and the welds from fabrication, shot blast machines, such as roller conveyor machines, are designed around these types of work pieces.

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Blast Cleaning Of Welded Constructions

These machines are capable of cleaning and descaling complex welded fabricated components and constructions. They are designed specifically to clean wide head and base plates, ribs, re-enforcements along with the welded seams after construction.

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All round blasting is achieved after 3D simulation and actual placement of the blast wheels in the optimum locations of the blast chamber. The chamber can be designed with 2 blast zones, each zone designed to blast clean the surface of the infeed side and the second, the outfeed side and end. As the fabrication passes through the chamber, all gussets, re-enforcements, ribs, angles are descaled and cleaned to Sa Swedish standards and with the desired profile to optimise the adhesion of the coating to be applied.

The equipment requires to easily meet the most stringent customer specifications regarding surface cleanliness and cost, for steel traders, steel fabricators, equipment manufacturers, shipyards and manufacturers of wind power stations. In wind power applications roller conveyor systems are utilised for shot blasting of the steel sheets or plate required for the fabrication of the towers for off-shore and land based windmills.

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Typical applications fall into these fabricating industries:

  • Steel traders/ distributors
  • Steel fabricators
  • Equipment manufacturers
  • Gas and oil
  • Aerospace
  • Power generation – including wind turbine columns
  • Transport – rail, bus, lorry, earthmoving, agricultural
  • Steel portal frame, tower block, stadium and steel construction
  • Bridge , crane, access, scaffolding and lifting gear

Partners for Steel

There are distinct benefits to be offered by the cooperation between the manufacturers of both shotblast equipment and multispindle drill/saw lines. The objective of cooperation (as partners for steel) is to support customers in resolving the interface problems between the various technologies, integrating shotblasting, measuring, marking, drilling and sawing or punching and shearing or coping and profiling thereby offering customers added value and profit from the processing of steel.

Click here for information on cleanliness standards

Click here for information on surface profile

For further information on roller conveyor shot blast machines please click here

 

Haydn Kitchen New APost written by
Haydn Kitchen
Shot Blasting Technical Manager

 

Structural Steel Descaling

Steel trading companies and fabricators shot blast their steel plate, sections and pipes to achieve a degree of surface cleanliness that is required before protective coatings are applied or other surface preparation needs.

Automated roller conveyor shot blast systems offer solutions which guarantee a highly-efficient descaling, rust /oxidisation removal and general surface cleaning of all kinds of steel.rrb

Shot blasting is a process for the surface treatment of plate, pipes, beams, tubes and bars.

Due to the design, roller conveyor shot blast systems are ideally suited for this application as it allows fast and highly-effective cleaning and surface preparation and at the same time, provides the surface with a profile to which a coating will adhere well, accommodating a wide- range of commercial to marine offshore standards.

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The equipment descales the surface of the steel ready to accept a first-class coating, or further engineering processes.

Equipment design and efficiency are paramount and should include the following as basic design and inclusions;

  • Infeed and outfeed vestibules should be long enough to stop abrasive escapement
  • The blast chamber itself should be constructed from wear-resistant manganese steel
  • The blast chamber requires to be further periphery lined with replaceable tiles again manufactured manganese steel, for durability
  • The blast requires to be delivered by a number of highly-efficient blast wheels set at an ideal angle to optimise the blasting coverage of the profile or plate
  • The blast wheels require to be driven by highly energy efficient electric motors, that are energy saving to the latest design standards of power efficiency
  • The system requires to recycle the abrasive and to include an airwash separation screen that is also highly-efficient in its function of separating out dust, scale and fines out to waste bins
  • Only good cleaned abrasive should be recycled back for re use
  • Abrasive level control is a vital inclusion, as without information, the efficiency of cleaning, repeatability and uniformity of the steel surface is all but impossible
  • A rotational brush and blow off unit, after blasting will complete the process and provides a very clean component that can be either removed from the outfeed conveyor or be handled automatically for further processing
  • Dust and contaminated air requires to be always drawn through the shotblast system under negative atmosphere, and passed through a very efficient cartridge-type dust collector/filter unit with a discharge back into the hall as low as 1mg/cu mtr down to 0.5 micron particulates and has an efficiency of upto 99.09%
  • By placing the cleaned spent air back into the building, residual and any ambient heat can be retained in the winter months which can contribute to the reduction of heating costs of the internal working environment

Generally, standard equipment concepts allow the processing of components from 1000mm wide, upto 5200mm wide and 600mm high. Other configurations may be offered as bespoke equipment and to accommodate more complexly designed fabrications.

Click here for information on cleanliness standards

Click here for information on surface profile

For further information  on roller conveyor shot blast machines click here

 

Haydn Kitchen New APost written by
Haydn Kitchen
Shot Blasting Technical Manager

 

 

A Complete Shotblasting And Painting Line

The demand for pre-finished quality steel sections, plate and tube is increasing throughout the world, year on year.  Many steel stockholders, distributors, fabricators and shipyards require their steel to be brought to the highest standard of cleanliness and coated for corrosion protection.

 

Preservation Line with Play Button cropped

Continue reading A Complete Shotblasting And Painting Line