October 22, 2015

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EVALUATION OF 20,000 PSI WATER JETTING FOR SURFACE PREPARATION OF STEEL PRIOR TO COATING OR RECOATING

EVALUATION OF 20,000 PSI WATER JETTING FOR SURFACE PREPARATION OF STEEL PRIOR TO COATING OR RECOATING

1983

Dr. Lydia M. Frenzel, Dr. Robert DeAngelis, Dr. John B. Bates

The original monograph which started the SSPC, NACE, and ISO to use waterjetting (hydroblasting, aquablasting) for coatings removal and surface preparation.

Click on the link to get the download.

frenzel deangelis bates 1983 White Paper

August 27, 2015

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Surface Preparation- Why surfaces with more surface area look darker.

Surface Appearance with Surface Area.

Back in the early 80’s, Dr. Lydia Frenzel and myself took a series of water-jet processed steel panels and examined them with a scanning electron microscope. We were hoping to receive confirmation of what our computer models told us; that is, water jetting at or above a threshold pressure produced surfaces with fractal properties. This property, we felt, would explain the observation that coatings over surfaces cleaned with high pressure and ultra high pressure water jetting exhibited remarkably enhanced adhesion values. “. Lydia Frenzel reported this thinking in “L.M. Frenzel and Jonell Nixon, Corrosion89, “Surface Preparation Using High Pressure water Blasting,” paper No. 397, NACE.” However, at the time, few took notice of this microscopic phenomenon or seriously considered that one day water would become “True Grit.”

A dozen or so years later, people are beginning to take seriously what cannot be seen with the eye and what cannot be felt with the finger tip. I think this has partly come about because we and others have been “hammering home” the idea that invisible salts on surfaces are a principle cause of premature coatings failures.

If your marketing arsenal of “reasons why you should use water in surface preparation” lacks punch, you should definitely obtain a copy of the paper by Thomas A Taylor entitled “Surface roughening of metallic substrates by high pressure pure waterjet”. This paper is to be found in “Surface & Coatings Technology”, 76-77,(1995) 95-100. Don’t call me for a copy, we don’t have the rights to reproduce the paper; so order this from your nearest major library.

This paper demonstrates (once again) that pure water jetting can and does produce surfaces which have far greater projected area than abrasive blasted surfaces, and that such area is obtained cleanly ( that is, without disturbing grain boundaries or creating fractures with occluded debris). Furthermore, such phenomenon is observed for threshold pressures as low as 32 Mpa for lnconel and much, much lower for softer substrates.

Surfaces with large areas (compared to projected area) tend to look dark. In fact, as the area of any surface increases, the surface darkens until, if you coat a surface with finely divide carbon particles oust about the ultimate in area), the surface will fail to reflect any appreciable light in the visible spectrum. Bright surfaces mean lots of flat, projected, smooth areas. This is the case of dry abrasive-blasted surf aces which are more like “grooved mirrors” with lots of occluded debris.

This is why we say that water jetted surfaces are more like “true” surfaces. Features as small as grain boundaries are preserved, indicating that, in general, such surfaces are “naturally” less active. While this is not a scientific term, it does describe what we generally mean by “clean”.

Charles Frenzel, At my desk, 1995

In 1995, Taylor, looked at the erosion of Inconel (IN 718) and titanium (Ti- 6AL-4V) with 345 MPa (50,000 psi) pure waterjet. (12) Taylor was concerned about individual droplets and cleaning [removal] of surface oxides from turbine blades. The threshold pressure for IN 718 was determined to be around 207 MPa (30,000 psi), with a velocity around 650 m/sec. This threshold of a water drop velocity threshold is compared to plexiglass at 150 m/sec, and for aluminum at 200 m/sec. Taylor reports “Excellent bonding of a thermal spray overlay was obtained with this surface preparation having an absolutely clean interface.”

“The striking point is that the detail of the eroded surface increases with increasing magnification, suggest the waterjet erosion produces a fractal surface. The highest magnification micrographs show a multitude of granular features of about 2 mm is size and rather micro-faceted. There is no indication of ductile fracture, but there are no long-running cleavage facets indicating brittle fracture either.”

“The structure of the waterjet-eroded surface is compared to the conventional alumina grit blasted surface in Figure 8[in Taylors’s paper] at the same magnification…. The feature size is at least an order of magnitude finer in the waterjet surface. In contrast, the grit-blasted surface would actually appear smoother as the magnification is increased, going from a long-range roughness pattern to smooth plateaus and facets, although there is micro-grooving due to the abrasion of the grit particle. The roughness of the grain blast surface is about 5.3 mm, while the waterjet surface is about 6.0 mm, much the same in magnitude but substantially different in detail.”

Surface Appearance with Surface Area discussion of Taylor paper Frenzel

July 8, 2015

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Lead Based Paint on Bridges- Cost Effective Alternatives- FHWA

I get questions about relative cost for various surface preparation methods and the pros and cons.  I refer people to this study as they can plug in their own numbers.

“COST EFFECTIVE ALTERNATIVE METHODS FOR STEEL BRIDGE PAINT SYSTEM MAINTENANCE” CONTRACT NO. DTFH61-97-C-00026

was published by the FHWA with Corrpro in September 2001.  The final product was a series of reports- found on the Advisory Council downloads page and an excel sheet so that contractors, specifiers, and owners could plug in their own numbers.

A cost model for bridge painting maintenance was developed to aid specifiers in
evaluating the costs associated with currently available painting technologies. A myriad
of design approaches, surface preparations, and coating systems are currently available to
engineers tasked with maintaining painted bridges. This cost model allows quick and
easy comparisons between many of the current options for steel bridge painting. The
information used for the model is based on actual field observations1 and current industry
practices. This “User’s Guide” describes the model’s primary components and features
and the basic operation of the cost model.

The following are two powerpoint presentations given on this project by Corrpro.  The reports are found on Advisory Council Downloads page which is in the upper left as I appear to have two different pages entitled “downloads”.

corrpro_TNRCC FHWA LBP July-2002

97C26 overview presentation Corrpro FHWA LBP Bridges Costs

October 28, 2014

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The Only Pipeline Integrity Congress Focused Specifically on Crude: Houston 19-Nov-2014

PS14_400x200

This year’s inaugural Crude Pipeline Asset Integrity Congress is the only event designed specifically for crude oil pipelines.

With the continual emergence of new shale plays across the US, crude production has continued to soar and crude takeaway capacity with it. Tens of thousands of miles of crude pipelines now traverse the United States and Canada and as pipeline infrastructure continues to expand at this rapid pace, it has become absolutely imperative for pipeline operators to maintain the highest level of integrity in these pipelines to maintain flow rates, avoid hazardous leaks and expensive repairs.

Crude pipelines and facilities require specific tools and considerations for maintenance. In order to deliver operators with the most comprehensive understanding of the latest, most effective integrity management tools relevant to their operations, solutions designed specifically for crude pipelines need to be presented.

“This is the only conference focused specifically on crude oil pipelines and 100% focused on the pipeline operator’s experience. We’ve put together a select group of pipeline operators and academics to deliver practical case studies on optimizing the main pipeline integrity plan. This is really a very valuable opportunity for operators to learn from each other and apply that knowledge to their day to day work.” Says Diana Franco, Conference Director.

Kinder Morgan, BP, ExxonMobil, Centurion Pipeline, Buckeye Partners and more are also confirmed to speak at the conference on 19-20 November in Houston.

For more information, please visit the event website here:

http://www.crude-pipeline-asset-integrity-2014.com/

October 27, 2014

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Ensuring the Success through Optimal Coatings Techniques 19-20 Nov 2014 Houston

PS14_speaking_at

Lydia Frenzel will be speaking on November 20, 2014 in Houston Texas.

The Only Crude Pipeline Operator-Led Congress Focused On The Entire Pipeline Asset Integrity Management Strategy: From Selection To Implementation

Website: http://www.crude-pipeline-asset-integrity-2014.com

Ensuring The Success Of A Project Through The Optimal Selection Of Coating Techniques

Reviewing NACE,-SSPC, ISO Surface Preparation Standards so the owner knows what they’re getting, the contractor knows what they’re supplying, and the paint manufacturer knows what they’re warranting

Exploring the three components of a perfect surface preparation to ensure performance

Understanding the logistics of removal of thick coal tar (coating) and tape to identify the most time-effective technique

Evaluating the economic parameters to decide whether to repair or to replace to justify capital expenditure

 

 

August 14, 2014

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Fixing Pipeline Problems; Performing Pipeline Rehabilitation Agenda 21- October 2014

Performing Pipeline Rehabilitation- Course Programme

21-22 October, 2014, Berlin Germany

www.clarion.org

DAY 1

Introduction

Deterioration Mechanisms                        Causes of pipeline problems and consequences

Rehabilitation Options                                What overall methods can be considered

In-plant Rehabilitation                               Reconditioning pipe in a stationary facility

Out of the Ditch Rehabilitation                  Case Studies of recoating a large diameter gas line in Canada and Russia

In-Situ Projects                                             Working on live lines

Case Studies- Oil Line                                   Recoating an operating large diameter of oil line in Kazakhstan and Canada

Case Study- Gas Line                                    Recoating an operating large diameter gas line in Canada

Inspection                                                       Inspection of the pipeline in the field

DAY 2

Internal Corrosion                                      Case studies of internal rehabilitation projects

Repair                                                            Methods for repairing pipeline defects in the field- pros and cons

External Strengthening of a line             Increasing the operating pressure of existing pipeline externally

Internal Strengthening of a line              Increasing the operating pressure of an existing pipeline internally

Coating Removal                                        Equipment available for removal of existing coatings in the field

Surface Preparation                                  Surface preparation equipment and product rates

Coating Materials issues                          Selecting the new coating and application equipment needed

Estimating Costs                                       Equipment and manpower requirements

Review                                                        Questions and Answers