How to Identify Plate Thickness Tolerance Using ASTM Code?

uhhhhhh, whatever happened to people actually reading themselves instead of being spoon fed?

SA-516:

3. General Requirements and Ordering Information

3.1 Plates supplied to this product specification shall
conform to Specification A 20/A 20M, which outlines the
testing and retesting methods and procedures, permissible
variations in dimensions and mass, quality and repair of
defects, marking, loading, and so forth.

oh, and you spelled 'Engineer' wrong in your footer.

Dear Mr.Hctoo,

SA516 refer ASTM -II A20/20M for material supplied conformation .

Mill tolerance 12.5% of plate thickness is acceptable.In your case 35mm plate thickness , plate thickness or vessel shell thickess shall not be less than 30.625 or minimum speficied thickness ( check design data sheet minimum calculated thickness+ corrosion allowance) in any place.

with Regards

If I bought 35mm plate that measured 30.625 it would be going back to the supplier regardless of mill tolerances .

That said I do buy 5mm plate that varies from a strong 5mm down to about 4.7mm in thickness . I do complain about the thinner stuff but as I am only a very small fry and my steel supplier never ring me looking for money , I tend to overlook their transgressions .

Good Luck !

"Mill tolerance 12.5% of plate thickness is acceptable.In your case 35mm plate thickness , plate thickness or vessel shell thickess shall not be less than 30.625 or minimum speficied thicknes" IS WRONG

Munneykhan - it looks like you are thinking about some piping tolerances.

For Metric, see A20/A20M TABLE A2.1 NOTE 1 -

NOTE 1 — Permissible variation under specified thickness, 0.3 mm.

Dear Mr. Guest,

if we refer to table A2.1 thickness 35mm and width is 2100 to 2400mm the tolerance of plate should be 1.4mm right?

Then why we need to refer to note 1? and what is the meaning of below note:

NOTE 1 — Permissible variation under specified thickness, 0.3 mm.

Thanks

The table itself provides OVER tolerance as per heading.

Tolerance Over Specified Thickness for Widths Given in Millimeters, mm

(the 1.4 value is OVER thickness)

So a 35mm thick x 2100-2400 mm plate thickness will be 35mm +1.4/-0.3mm or

34.7 < thickness < 36.4 mm

ASME Section II is a regurgitation of the ASTM material specifications ASME has adopted. However, Section II is the official guide for ASME. I would start there. If you don't have a copy, go to the nearest engineering school's library. Your local library may have a copy. Even an old copy will do, for the most part as very little changes for the subject at hand.

Hi

The ASME Sec.II Part A , SA-20 is the " specification for general requirements for steel plates for pressure vessels "

G.R.H