ASTM B521-98 pdf free.Standard Specification for Tantalum and Tantalum Alloy Seamless and Welded Tubes.
The finished tube shall be clean and free of foreignmaterial, shall have smooth ends， free of burrs，and shall befree of injurious external and internal imperfections in accor-dance with standards of acceptability agreed upon between themanufacturer and the purchaser. Minor defects may be re-moved provided the dimensional tolerance of Section 9, are notexceeded. If any sample or specimen exhibits obvious surfacecontamination or improper preparation disqualifying it as atruly representative sample,discard it and substitute a newsample or specimen.
In case of failure, retest two additional specimens.Ifboth specimens conform to this specification，discard theoriginal values and consider the material acceptable.If the inspection results of a lot are not in conformancewith the requirements of this specification，the lot may bereworked at the option of the manufacturer. A lot shall beacceptable if results of all tests after reworking conform to thespecification.
Significance of Numerical Limits: For the purpose of determining compliance with thespecified limits of property requirements, an observed value ora calculated value shall be rounded in accordance with therounding method of Practice E 29.
The manufacturer shall inspect the material covered bythe specification prior to shipment.If so specified on the purchase order, the purchaser orhis representative may witness the testing and inspection of thematerial at the place of manufacture. In such cases，thepurchaser shall state in his purchase order which tests hedesires to witness.The manufacturer shall give ample notice to the purchaser as to the time and place of the designated test. If
the purchaser’s representative does not present himself at the agreedupon time for the testing, and if no new date is agreed upon, the manufacturer shall consider the requirements for purchaser’s inspection at the place of manufacturer to be waived. When the inspector representing the purchaser does
appear at the appointed time and place, the manufacturer shall aford him all reasonable facilities to see that the material is being furnished in accordance with this specifcation. This inspection shall be conducted so as not to interfere unnecessarily with production operations.ASTM B521 pdf download.