Letter 12526

Swedish standard SA 2.5, SA 3 for sand blasting for cast iron part 

I need to know the technical details about the following- Surface preparation - Cast Iron part ( gratings, used for cooking ranges); the surface needs to be prepared by sand blasting as per Swedish Standard , SA 2.5 minimum or better as per Swedish Standard , SA 3. If it is possible then please inform about the surface finish value ( Ra, Rmax eg.) which can be achieved by the above mentioned process. lease respond as early as possible. Best Regards, Souren Pal steel company - Ahmedabad, Gujarat, India   Dear Mr. Souren Pal, I am also interested in the relationship between the SA standards SA 1, 2 21/2 and 3 and Ra. An interesting answer on your question which may be of help to me? Best Regards, Laure Spriensma - Jirnsum, The Netherlands   I WOULD LIKE TO INQUIRE INFORMATION REGARDING SAND BLASTING PROCEDURES, EQUIPMENTS AND MATERIAL, AS DESCRIBED IN SWEDISH STANDARD SA1, 2, 2.5, 3? YOUR COOPERATION ON THIS MATTER WILL BE HIGHLY APPRECIATED. FADI MUSALLAM - ABU DHABI, UAE   Mr. Souren Paul , Laure Spriensma, Mr. FADI MUSALLAM,

Surface preparation standards are stipulated by various bodies throughout the world to designate the cleanliness condition of blasted steel, prior to applying a protective coating. The applicable cleanliness standard is usually called for by either the protective coating manufacturer or the owner of the structure to be painted. The most commonly referred to standards are SSPC, NACE, and Swedish Standards. Each standard is divided into four standards of cleanliness, broadly described as follows; brush off, commercial, near white metal, white metal. Whilst each standard may differ slightly in requirements and terminology the following cross reference chart indicates the close approximation of each level of cleanliness for each standard.

BRUSH OFF COMMERCIAL NEAR WHITE METAL WHITE METAL SSPC SP 7 SP 6 SP 10 SP 5 NACE No.4 No.3 No.2 No.1 SWEDISH Sa.1 Sa.2 Sa.2.5 Sa.3

A brief description of each of the four levels of cleanliness is as follows: Brush Off - Loose mill scale, loose rust and foreign particles are removed.

Commercial - Mill scale, rust and foreign particles are substantially removed and grey metal is visible.

Near White Metal - Mill scale, rust and foreign particles are removed to the extent that only traces remain in the form of spots or stripes. The cleaned surface will show varying shades of grey. White Metal - Visible mill scale, rust and foreign particles are entirely removed. The cleaned surface should have a uniform metallic colour but may show varying shades of grey when viewed at different angles.

I hope the above info is useful to you. We are setting up a shipyard and are installing a plate preparation shop.

Regards,

Bijit Sarkar
shipbuilding - Calcutta, WB, India

Grit blasting. SA 2.5 .... what what is it ? and Y SA 2.5 Y not 4.5 or what ever looking forward for ur reply

Yasir Al-Mahrooqi
Royal Court Affairs - Oman, Muscat

May I know the surface profile difference between SA 2.5 and SA 3 in microns?

Shahaji Doltade
- UAE

Please give me the details of S.A. 2.5. Where can we purchase this standard?

Kuldeep Bhat
employee - India

What is Sa 2.5 and Sa 2 1/2
Please explain elaborately for the above (with technical support)

Venu Gopalarao
student - Angul, Orissa, India

I hope this will clear your all l queries on Blasting and surface preparation..

ABRASIVE BLASTING DATA
BLAST CLEANING - PREPARATION GUIDES

grade - BS 7079 SS 05 59 00

description

when viewed with the naked eye
SA 2

thorough blast cleaning:Commercial finish 65% clean


The surface shall be free from visible oil, dirt and grease, from poorly adhering mill scale, rust, paint coatings and foreign matter. Any residual contamination should be firmly adhering.
SA 2.5


very thorough blast cleaning: Near white metal 85% clean

The surface shall be free from visible oil, dirt and grease, from poorly adhering mill scale, rust, paint coatings and foreign matter. The metal has a greyish colour. Any traces of contamination shall be visible only as slight stains in the form of spots or stripes.
SA 3

blast cleaning to pure metal: White metal 100% clean

The surface shall be free from visible oil, dirt and grease, from poorly adhering mill scale, rust, paint coatings and foreign matter. The blasted surface must have a uniform metallic colour.

BLASTING GRADES Following is a table giving a clear indication of the comparative blasting grades applicable to national and international standards: BLASTING GRADE COMMON STANDARDS COMPARISON SSPC steel structures painting council BS 7079 British standards SS 05 59 00 Swedish standards BS 4232 NACE National Association of Corrosion Engineers white metal (SP5) SA 3 1st quality grade 1 near white metal (SP10) SA 2.5 2nd quality grade 2 commercial finish (SP6) SA 2 3rd quality grade 3 RUST GRADES A Surface mostly covered with adherent mill scale, with little or no rust B Mill scale has begun to flake, rust has started to form C Mill scale has rusted away or can be scraped off easily and slight pitting has taken place D Mill scale has rusted away and general pitting can be seen with naked eye Sanjay Mungee - Baroda, Gujarat, India March 17, 2009 Please explain the letters "Sa" in blast cleaning, and, how and where these letters came from? Eswaramoorthy Velu painting employee - Abudhabi, U.A.E.   opt

dear sir

we want photographs of standard blasting like as sa 2, sa 2.5, sa 3 etc.

regards

KIRIT D. PARMAR
reliable coatings - Vadodara, Gujarat, India