... size 2. F316, F51,35CrMo, 36CrNiMo4 and so on 3. Heat treatment 4. detailed record cards of process 1 ... ,NF,GOST,EN,ISO and Non standard,4. Size:1/2"-48"5. Type:Slip-on flanges, Blind flanges, Lap joint ... 40 64 and 160, 150LBS-2500LBS ,5K-40K and so on .7. Sealing surface : FF ,RF, LJ, FM ,RTJ ... ,RJ ,MALE ,FEMALE and so on .8. Used for : petroleum,chemical,power,gas,water,linepipe, heat ...