New Build-Brazil; ISO Meeting
Trip Report
NACE Corrosion 2016 March Vancouver BC
By: Lydia Frenzel
I, Lydia Frenzel, scrutinized the program to see if the UHP WJ/ paint maintenance community might find a niche for applications as this conference has paint/coatings, railcar, marine, and pipeline sections but focuses on corrosion, cathodic protection, alloys-and metals. Prior to the NACE Corrosion2016 meeting, Frenzel had perused the titles to see if there was justification to register for the full meeting and go to technical papers during the four days. I decided to spend time in the exhibit hall, and to register for one day in order to chair the ISO TC35 Technical Advisory Group (TAG) on Wednesday.
- There were about 100 papers with paint, coatings, or linings in the title, but were fairly esoteric.
- Chemical Cleaning and Mechanical cleaning held a Technology Exchange Group
- There was a Technology Exchange Group on Surface Preparation issues, and
- committee meeting on “Soluble Salt Testing Frequency and Locations on Previously Coated Surfaces.” This development of a standard practice has a mirror committee at SSPC. The two documents are being handled separately, rather than as a joint standard.
- There was one title of interest at the Marine Technology Exchange Group for a presentation by “UHP Water-jetting and Surface-Tolerant Coatings in New Building Applications”, by Nuno Cipriano, Director at Narus Auditoria & Consultoria, Brazil. See JPCL, July, 2015, p. 42 for his paper.
None of the above TEG (Technology Exchange Group) presentations are included in the proceedings. The papers and TEG’s are considered informal and do not follow the rigorous time table of paper submission. The agenda and speakers of an TEG might, or might not, be announced in advance of the meeting, and is most likely not in the pre-publication information.
I obtained from Nuno Cipriano a copy of his presentation slides, which you can obtain upon request to me.
Proceedings Papers
- Proceedings papers which I feel are of interest to this specific email group include:
- “Effect of Surface Profile on Coating Adhesion and Corrosion Resistance”- Norwegian University of Science, Hagen, Corrosion2016 7518
- “Expected Service Life and Cost Considerations for Maintenance and new Construction Protective Coating Work”- KTA-Tator, Heisel, CORROSION2016 7422
- “Residual Soluble Salts and Coating Performance- Separating Myth from Reality”- Rogers & Assoc., Rogers, CORROSION2016 7539
- “Making Mud-Cracking IOZ’s a Thing of the Past” Hempel, McDonald, CORROSION2016 7835
- “Coating Deterioration – A Mechanistic Overview”; KTA-Tator, Tator, CORROSION2016 7065
At the exhibition itself, “nano” was the overwhelming buzz word for all sorts of coatings and processes. There were several thermal spray coatings, inhibitors or microbial biocides which were encapsulated as nano-spheres within the coatings for self-healing properties or to release as needed; field specialty kits for collecting microbes and determining what they were for more effective control of microbial induced corrosion (MIC). There were few true techniques of nano-chemistry or technology.
Wet Abrasive Blast Cleaning
Because the Wet Abrasive Blast Standards had just been released, I talked with many people who were curious about WAB, mainly because Graco is heavily advertising their Wet Abrasive Blast Cleaning System under the Trade Name “Vapor Blast.” One back story emerged. Graco had purchase “EcoQuip,” but found some difficulty with the equipment or process. Graco then purchased “Geoblast” which was more robust. Graco kept the Ecoquip name, while the final process is closer to the Geoblast. This back story cleared up some confusion which I had because I had noticed a name and emphasis shift during the start-up of the Graco marketing message.
Discussion Meetings at the exhibition hall.
- TermaRust HRCSA use on Bridge in England
I met briefly with Josef Soltis, Senior Corrosion Engineer, with Macaw Engineering from Newcastle-upon-Tyne. He was monitoring a bridge that had been coated with TermaRust HRCSA material; the bridge went under brackish water during the recent floods in England. TermaRust is used as an overcoat where the surface preparation Is 6000-7000 psi pressure washing with hand tools to remove remaining rust as needed. Soltis appeared to say that the TermaRust worked well and continued to perform. When asked about any drawbacks, he noted that it remains softer than conventional coatings. This is true because TermaRust HRCSA is not carried in a cross-linked polymer as a traditional coatings binder. To my thinking, this lack of brittleness is the element which makes TermaRust ideal for structures, such as bridges and exterior of riveted tanks, which have some movement or vibration; this condition needs a non-brittle coating to creep into crevices and around rivets. It is not an abrasion resistant coating.
Soltis had also used an English product called Chlor-X for washing the bridge. My follow-up research on Chlor-X comes from the web site (rust.co.uk) which describes washing marine engines, boats, fishing tackle, car or bus, and prior to painting steel. It appears to be a wash additive.
- UHP WaterJetting in Brazil
Nuno Cipriano, from Brazil, and I had a long discussion as he went through the features and decision for Petrobras and the overall Brazilian maintenance industry to adopt UHP WJ, and displace abrasive blast cleaning. See JPCL, July, 2015, p. 42 for his paper. He went through all the environmental, health, and productivity points that have been developed over the years. Also present at the meeting was a UHP WJ cutting expert who was not so familiar with the aspect of coatings removal, so Nuno and I hit upon many fundamental topics as to why use UHP WJ in place of abrasive blasting. Nuno is talking about both new build and maintenance. Estaleiro Atlantico Sul Shipyard (EAS) put in blast cabins to use only UHP WJ- and found the SY construction was much simpler and economically more appealing. A newer shipyard also adopted UHP WJ and put all the equipment into a central location. They treat their effluent water with 100% recycling. (See JPCL paper for more details)
Brazil placed strong mandates against abrasive blast cleaning about 20 years ago. They had to find a substitute starting in the 1990’s and making the conversion to new build about 2008 specifically for Ballast Tanks for International Maritime Organization (IMO). Nuno specifically mentioned Singapore and LisNaves in Portugal for new build. He did not specifically mention the Blohm and Voss Shipyard in Hamberg. Joaquim Quintela, Fernando Fragata, and Carols Augusto were advocates in Brazil.
On Costs
The overall process of WJ removal is less expensive because there is a smaller waste stream, and there is less containment and cleanup. Dust from abrasives gets everywhere. It is easier to collect and filter the water.
On Safety and Health
They have found that the WJ is safer. When a person gets hit with a sand blasting, grit is hard to get out. They have less worries about dust drifting in the air. Their overall conclusion: they can work with dangerously high water pressure, buth UHP WJ offers fewer overall health risks due to absence of abrasive media.
Their safety zone is around 3 meters (ca 10 feet); The WJTA Orange book recommends 15 feet (5 meters), but when Capriano questioned me about that safety factor, I did not know of tests to establish the distance. I have observed some US companies using the 15 feet and in generally extending it to 25 feet (8 meters) radius, with a warning- don’t get closer than 6 feet from the UHP WJ nozzle. This warning is individual company policy.
On safety ppe, the Brazilians use a local suit made of Aramid. They are mostly concerned with the waist and below. The overall suit from TST proved to be too rigid and their men can’t work effectively. He felt that the workers need mobility.
On Performance and Paint Systems
Nuno stressed that they use wet surface-tolerant paints, and sometimes a combination of UHP WJ and abrasive blasting. Brazil uses the surface -tolerant coatings for ease of application and to face varying weather conditions during application. The paint systems has to be typed approved by IMP PSPC.
On other global Experts
We talked about Raoul Kattan from Sarafinah (in the UK) whom I have known for years. Raouf and I had discussed some years before how to get the savings of UHP WJ into the bid process. Raouf had said that an obstacle was knowing that the UHP WJ is faster in turn around, even though it is likely a little more costly in cents/square area.
Nuno stressed that UHP WJ was faster because other trades were working in the same area.
Nuno talked about the removal of contaminants in the maintenance projects, and generally washing the surface to increase coating performance.
Future Considerations
What would Nuno like to see: Removal of mill scale.; production of a profile. He can always put on an abrasive induction head, but then the safety requirements change.
Nuno will like to increase productivity. Cost per square meter is comparable to abrasive blasting or less in the overall project. He spoke of removing 2000 sq meters in 5 hours with 12 guns which translated into 20 -30 square meters per gun.
Specifically he is speaking about removal of rust, not conventional coatings. In his opinion, WJ is better at removal of rust. Abrasive blasting is faster in removing conventional 300-400 micron (6-8 mil) coatings.
You must use moisture surface tolerant coatings when removing the rust. The profile is uneven. IMO looked for coatings that could go over moisture and light-to moderate flash rust developed as the water is drying. One coating system received IMO PSPC- approval that could be applied at block stage over UHP WJ bare metal.
On design of the Cleaning Head
Nuno liked the “Chariot Robotic” remote head- it is very fast and mobile. When doing spot and sweep blast, the head will lift about 1-2 inches from the surface to allow the partial removal.
On the steam or Fog which surrounds the WJ impact area.
The fog which steams radially from where the waterjet hits the surface is a problem in limiting vision to see what is happening. For manually held equipment, Nuno did not think that a vacuum attachment at the nozzle be effective as it is a lateral fog, not a splash back. This could be limiting for interior work. It is a different type of vision impairment when compared to the grit blasting.
On Manual Guns
Nuno likes the “Jetstream” guns. He said that some gun design have the hose connection at the gun going straight back. The jetters make a loop or U bend in the hose and rests it on the shoulder to absorb the shock; as the butt is not positions correctly. In my mind, this makes for an unsafe working practices as the hose U is between the shoulder and the gun. When Nuno said this, I just cringed at the thought of a jetter with a pulsating hose loop on the shoulder blade. This will affect the jetter’s choice of equipment.
KEY to SUCCESS: Full time maintenance crew.
Do not let the equipment run until it breaks down. I have heard this over and over. A company gets WJ equipment and then treats it like a compressor and blast pot [not maintained until it breaks]. This is a recipe for disaster. I have found that the more successful companies do not have the jetters also try to maintain the equipment; The company should have a dedicated equipment maintenance person on site. If something doesn’t operate right; set the gun down, and call the equipment person.
Filter the incoming water. They are using local filters as EOM filters were way, way too expensive. He faulted the manufacturers for not concentrating on supplying the parts which needed to be OEM, and telling the contractors or users that they could use local filters. Nuno uses filters which are more stringent than the equipment specifications. They use boiler water.
Nuno would like to see the lifetime of hoses improved. As a company, they stress keeping the gun on- not a lot of on-off repetitions, however their hose life is about 200 hours per hose. They spend 80 to 100,000 reals a month on hoses. This is a major expense. My overall impression is that the hose comes loose at the coupling or crimp. Nuno did not talk about hoses splitting.
The Summary:
Overall the productivity is faster with WJ.
The safety is better with WJ.
The cleanup is easier.
The cost is competitive.
They would not go back.
There is room for improvement.
ISO Meeting
NACE sponsors the USA Technical Advisory Group (TAG) for ISO TC 35 (Paints and Varnishes) to supply the US position through ANSI to ISO. Other organizations such and ASTM is responsible for other ISO Activities.
Lydia Frenzel is the ISO TC35 Liaison Chair. I can easily spend a half day every week-day just reviewing documents, drafting responses, and coordinating the comments of the USA country experts. NACE has a staff member, Ed Barrett, who works essentially full time on the international Standards preparation; NACE has also committed the funds required to administer this portion of ISO activities.
At the meeting, we looked briefly at the 29 standards that had been circulated in 2015. In addition, there are several other standards from Marine or Pipeline TC’s which were reviewed but didn’t require formal response from TC35 TAG. I review every standard for inclusion of methods other than conventional abrasive blasting, or power tools, as many of them were written and adopted in the 1990’s and need updating. For Advisory Council Supporters who are in WJ or WAB or Bristle Blast, I check the methods; for Advisory Council Supporters in paints, I check for inclusion of newer coating systems or wording that tacitly excludes newer coatings; for Advisory Council Supporters who have water additives, I check for exclusionary language; for Advisory Council Supporters in test equipment, I check the methods, some of which are written 20 years ago, to see if there have been newer changes and send them to the specific equipment/testing experts on the panel.
As a group, we are concerned that the Working Groups (WG) which are chaired by Europeans give us sufficient notice and work together so that we can avoid the increasing trend to announce, with minimal advance warning, one day meetings in Europe. In particular, there is a TC35 meeting in Tokyo which had been announced for years, and normally would be the place for multiple WG’s to meet face-to-face. Instead, the Tokyo agenda is very sparse.
The individual WG chairpersons appear to be deliberately avoiding the travel to Japan by holding small meetings in Europe, as an example there is an one day WG meeting, announced in March, which is in Europe which is 2 weeks before Tokyo. The USA feels that such action disenfranchises several countries for participating as our individual Country experts are volunteers and depend upon their employers to fund travel.
As TC35 liaison chair, I have drafted a US position paper of Support which was sent to the ISO TC35 Chair and the host in Japan through ANSI. Ken Tator noted that Japan will be hosting the Korean and Chinese country organizations; it is a great opportunity to build Asian cooperation. We are trying to use our influence so that Japan is not embarrassed by the lack of participation by certain European members of ISO. ISO objective is inclusion of global interest, not exclusively European.