XN-85™ - Nu-Saf™

Performance Features

  • Designed for gas service (acceptable for liquid service with a compressible gas/vapor pocket)
  • Suitable for operating pressure to 85% of the marked burst pressure (90% of the minimum)
  • Designed for non-fragmentation, recommended for Relief Valve isolation
  • Damage safety ratio ≤ 1
  • Suitable for cycling service
  • Vacuum resistant
  • Available with ASME “UD” (select 0%, -5%, -10% Manufacturing Design Range)
  • Pressure Equipment Directive “CE” marking and/or other International Certifications
  • BS&B proprietary technology

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  • Sizes & Pressures
  • Burst Tolerance
  • Safety Heads & Sensors
  • Accessories
  • Documentation

Sizes & Pressures

XN-85™ Disk Specifications Minimum/Maximum Pressure with Rating at 72° (22°C)

Disk Size Nickel Alloy 200 Monel Alloy 400 Inconel Alloy 600 316SS Aluminum
in mm psig barg psig barg psig barg psig barg psig barg
min max min max min max min max min max min max min max min max min max min max
1 25 188 1500 13 103 225 1500 16 103 225 1800 16 124 335 1800 23 124 113 199 8 13
1.5 40 135 1500 9 103 165 1500 11 103 165 1800 11 124 250 1800 17 124 81 135 6 9
2 50 113 1350 8 93 135 1350 9 93 135 1800 9 124 200 1800 14 124 68 113 5 8
3 80 90 1250 6 86 108 1250 8 86 108 1600 8 110 160 1600 11 110 54 90 4 6
4 100 75 1200 5 82 90 1200 6 83 90 1400 6 97 135 1400 9 97 45 75 3 5
6 150 60 1100 4 76 72 1100 5 76 72 1150 5 79 125 1200 8.6 83 36 60 3 4
8 200 53 1000 4 69 63 1000 4 69 63 1050 4 72 120 1100 8 76 - - - -
10 250 45 900 3 62 54 900 4 62 54 950 4 66 115 1000 8 69 - - - -
12 300 41 750 3 52 50 750 4 52 50 850 4 59 110 900 8 62  - - - -
14 350 35 500 2 34 42 500 3 34 42 700 3 48 100 800 7 55 - - - -
16 400 33 200 2 19 39 270 3 19 39 350 3 24 90 400 6 28 - - - -
18 450 33 200 2 14 38 200 3 14 38 260 3 18 85 300 6 21 - - - -
20 500 32 170 2 12 36 170 2.5 12 36 220 2.5 15 80 250 5.5 17 - - - -
24 600 30 140 2 9 33 140 2 9 33 180 2 12 70 200 5 14 - - - -
Optional liner: liners are available in all sizes on the process or downstream side (or for both; consult factory). Fluoropolymer film application range -40°F to 500°F (-40°C to 260°C)

Burst Tolerance

Marked Burst Pressure Burst Tolerance
≤ 40 psig (2.76 barg) ± 2 psig (0.138 barg)
> 40 psig (2.76 barg) ± 5%

Accessories

BS&B supplies many of the accessories required to safely and conveniently install our overpressure relief devices and complementary products. Through our professional team and global network of sales engineers and procurement personnel, we are able to provide the highest quality accessory products to meet your installation requirements.

Saf-T-Change Quick Disk Replacement (QDR)

After activation, the replacement disk is quickly slid into place. Saving hours of lost production due to blown rupture disks.

Tell-Tale Assemblies & Excess Flow Valves/Gauges

A gauge tap in the outlet flange of the safety head may be considered when the safety head is installed in a vertical position.

Spare Safety Heads & Cap Screws

Jackscrews

When activated, the jackscrews effectively separate the flanges, providing adequate clearance to remove or insert a safety head and external gaskets.

Lifting Lug Eye Bolts

Eye bolts are recommended when weight and/or accessibility is a factor in lifting safety heads.

Baffle Plate

When a safety head is free-vented to atmosphere, a baffle plate may be considered to disperse overpressure and absorb recoil.

Product Literature

Nu-Saf™ Series Scored Forward Acting Rupture Disks
Saf-T-Change™ QDR Rupture Disk Replacement System
Burst Alert Sensors
Detec Saf Alarm System - Burst Disk Monitor