CARBON STEEL FOR FLANGES :  
ASTM A105/A105N .A350 LF1, LF2 CL1/CL2, LF3 CL1/CL2
 A694 F42, F46, F48, F50, F52, F56, F60, F65, F70
 A516.60, 65, 70 (Spectacle Blind Flange, Spacer Ring/Spade Flange   
STINLESS STEEL FOR FLANGES :
ASTM A182 F304/304L, F316/316L, F316H, F316TI, F310, F321;
Alloy Steel: ASTM A182 F1, F5, F9, F11, F22, F91
Duplex & Super Duplext Steel: ASTM A182 F51/UNS S31803, A182 F53/UNS S32750

Nickel alloy forged flange :
Alloy 200/Nickel 200/NO2200/2.4066/ASTM B366 WPN;
Alloy 201/Nickel 201/NO2201/2.4068/ASTM B366 WPNL;
Alloy 400/Monel 400/NO4400/NS111/2.4360/ASTM B366 WPNC;
Alloy K-500/Monel K-500/NO5500/2.475;
Alloy 600/Inconel 600/NO6600/NS333/2.4816;
Alloy 601/Inconel 601/NO6001/2.4851;
Alloy 625/Inconel 625/NO6625/NS336/2.4856;
Alloy 718/Inconel 718/NO7718/GH169/GH4169/2.4668;
Alloy 800/Incoloy 800/NO8800/1.4876;
Alloy 800H/Incoloy 800H/NO8810/1.4958;
Alloy 800HT/Incoloy 800HT/NO8811/1.4959;
Alloy 825/Incoloy 825/NO8825/2.4858/NS142;
Alloy 925/Incoloy 925/NO9925;
Hastelloy C/Alloy C/NO6003/2.4869/NS333;
Alloy C-276/Hastelloy C-276/N10276/2.4819;
Alloy C-4/Hastelloy C-4/NO6455/NS335/2.4610;
Alloy C-22/Hastelloy C-22/NO6022/2.4602;
Alloy C-2000/Hastelloy C-2000/NO6200/2.4675;
Alloy B/Hastelloy B/NS321/N10001;
Alloy B-2/Hastelloy B-2/N10665/NS322/2.4617;
Alloy B-3/Hastelloy B-3/N10675/2.4600;
Alloy X/Hastelloy X/NO6002/2.4665;
Alloy G-30/Hastelloy G-30/NO6030/2.4603;
Alloy X-750/Inconel X-750/NO7750/GH145/2.4669;
Alloy 20/Carpenter 20Cb3/NO8020/NS312/2.4660;
Alloy 31/NO8031/1.4562;
Alloy 901/NO9901/1.4898;
Incoloy 25-6Mo/NO8926/1.4529/Incoloy 926/Alloy 926;
Inconel 783/UNS R30783;
NAS 254NM/NO8367;
Monel 30C
Nimonic 80A/Nickel Alloy 80a/UNS N07080/NA20/2.4631/2.4952
Nimonic 263/NO7263
Nimonic 90/UNS NO7090;
Incoloy 907/GH907;
Nitronic 60/Alloy 218/UNS S21800

A spectacle blind is a safety device used to isolate process piping or equipment when the line or equipment needs to be inspected or removed from service. It is different than a valve in that the spectacle blind is a permanent or long-term isolation device.  Delta primarily builds to ASME B16.48 but can build to any specification needed.