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Swedish Standard SA 2.5 shot blasting / surface prep
Q. I need to know the technical details about the following- Surface preparation - Mild steel part the surface needs to be prepared by sand blasting as per Swedish Standard , SA 2.5 minimum or better as per Swedish Standard. If it is possible then please inform about the surface finish value ( Ra, Rmax, e.g.) which can be achieved by the above mentioned process.
Please respond as early as possible.
Best Regards,
SRIHARIKOTA, A.P., India
2002
A. Hi, T.N.C.. This is a Swedish Institute for Standards designation for "near white" blasted finish -- approximately equivalent to
NACE No. 2/SSPC-SP10, and
ISO 8501-1 WA.2.5
I believe it's actually "Sa.2.5", but I don't know if "Sa" is an abbreviation or acronym in Swedish. It is a visual standard, rather than something you measure with a profilometer.
Please see letter 12526 for a more complete explanation. Good luck.
Regards,
Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
Multiple threads were merged: please forgive repetition, chronology errors, or disrespect towards other postings [they weren't on the same page] :-)
Roughness as per Sa 2 1/2
Q. For the preparation of CS surface I need to know the grit profile from blasting as per Sa 2-1/2 (roughness). Thank you in advance for your prompt answer.
Omar KhericiOil and gas project - Almaty, Kazakhstan
2004
A. Hi Omar. Although there are standards for roughness, Sa 2-1/2 is not a roughness standard, it's a cleanliness standard. There is no specific roughness associated with it.
Regards,
Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
Surface preparation without any surface preparation standard
Q. What is the standard surface finish values (e.g Ra, Rmax) or units used to measure the surface finish of structural steel products.
What is the importance of surface preparation per SA 2.5. Where can I get hold of this spec - SA 2.5
What are the technical details of this spec Swedish Standard, SA 2.5. What will be the acceptance criterion for shot blasting -- prime or reject.
If product are shotblasted without reference to any surface finish spec, e.g SA 2.5, there will be any conflict/disagreement between the manufacture/purchaser?
Plate manufacturing (rolling & heat treatment) - VANDERBILJPARK, GAUTENG, South Africa
2004
Profilometer: Mitutoyo
on
eBay
or
Amazon
(affil links)
A. Hi Felix.
Sa 2.5 is a cleanliness standard, not a surface roughness standard. An example of a surface roughness standard would be ISO 8503.
One reason cleanliness is required is because paint will not adhere properly to a dirty surface.
If you offer any service without reference to a spec, just expecting agreement with your customer about "implied industry methods" there is a significant chance of conflict after the job is completed; it's a bad idea :-(
Regards,
Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
Method for sandblasting to SSPC Sa 2.5
Q. We are repairing our existing navigational buoys. we want to know about sandblasting method conforming to SSPC Sa 2.5 standard. please help us. thanks!
Genesis G [last name deleted for privacy by Editor]construction business - Subic, Philippines
2006
A. Sa 2.5 equals SSPC 10. Sa is Swedish standard which is often used in marine work.
Regards,
- Concord, California
2006
A. SA2.5, also known as near-white blast cleaning is a method of preparing steel surfaces which, when viewed without magnification, shall be free of all visible oil, grease, dirt, dust, mill scale, rust and paint / coatings. Generally evenly dispersed very light shadows, streaks and discolourations caused by stains of rust, mill scale or previously applied paint / coatings may remain on no more than 5% of the surface
Marilyn Rushworth- Halifax, England
2006
Multiple threads were merged: please forgive repetition, chronology errors, or disrespect towards other postings [they weren't on the same page] :-)
Q. What is Sa 2 1/2 regarding surface preparation. and Sa stand for what?
dushyant upadhyay- varansi, u.p., India
September 3, 2009
A. Hi, Dushyant. This is a Swedish Institute for Standards designation for "near white" blasted finish -- approximately equivalent to NACE No. 2/SSPC-SP10 2, and
ISO 8501-1 WA.2.5
I believe it's actually "Sa.2.5", but I don't know is "Sa" is an abbreviation or acronym in Swedish.
Please see letter 12526 for a more complete explanation.
Regards,
Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
September 3, 2009
Q. Hello,
My question is kind of a general one. I was wondering if shot blasting process is applied for more surface area creation for the primer to adsorb or it's done only for cleaning the rust on metal pieces? For example I have got a metal piece and I'm asked to shotblast it to SA 2.5 norm. What will happen if I apply primer and paint within 310-450 micrometers thickness but shotblast isn't SA 2.5? Will the paint peel within time? Will shotblasting in SA 2.5 give my paint a longer life for it to stick onto the metal?
Thanks for sharing your time and I appreciate all help!
- Turkey, Istanbul
December 14, 2016
A. Specifications are basically acceptable guidelines. Meaning that if you do not conform to the specifications you will probably not achieve the surface finish or life span that the process is designed to produce. You will still get a surface that will accept a secondary process; however, the over all results will fail the time element.
AF Kenton
retired business owner - Hatboro, Pennsylvania
December 19, 2016
Q. What is the difference between a Swedish standard and British standard and American standard?
D. RajkumarDynamic engineering - Tamilnadu, India
March 2, 2018
A. Hi Rajkumar. There are also Indian standards. Anyone from any country, company, or organization can write any standard they wish ... although usually the standards writers do try to make their standards similar, and the more useful standards do tend to be adopted more universally than others. But there are no guarantees that any spec is equivalent to any other spec.
Regards,
Ted Mooney, P.E. RET
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
March 2018
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