supply of branch pipe 20 n.b. with socket & flange (welded assembly)branch pipe 20 n.b. with socket & flange (welded assembly),branch pipe 20 n.b. with socket & flange (welded assembly) to rdso drg. no. wd-80 007-s-11, alt.no.12, item nos. 5, 15 & 16. details of socket & flange to rdso drg. no.wd-83062-s-07 , alt.no.-6, item no.-2 & 3. other technical requirements confirming to rdso specification no.04-abr -2019, material specification of pipes is as under, pipes 20 nb- stainless steel to astm-a 312 schedule 40 s gr.tp 304 (seamless). flanges & socket - stainless steel to is: 6911-2017 with amendment 5, gr ade: x 04 cr 19 ni 9- 304 si. [ warranty period: 30 months after the date of delivery ] [quantity tolerance (+/-): 5 %age , item category : normal , total po value variation permitt ed: max 8 lacs ] ]