The VAC-SAFTM System rupture disks can be utilized in various ways:
Type DKB
For vacuum and over pressure relief in a KB-7R Safety Head, for installation between standard pipe flanges.
Type VKB
For vacuum and over pressure relief in a KB-C Safety Head with- hygienic fittings.
Type P/DKB
For light over pressure relief in a PKB-7R Safety Head, for installation between standard pipe flanges.
Type P/VKB
For light over pressure relief in a PKB-C Safety Head with hygienic fittings.
The VKB rupture disk (bursting disc) with the KB-C Safety Head meets the requirements of the American 3A Sanitary Standards. The KB-C Safety Head and VKB disk provide a uniformly smooth, noncontaminating and non-corrosive environment towards the products. The assembly is ideal for situations where frequent situation dismantling is required for product changes and cleaning purposes.
Applications for Protection
- Storage Tanks
- Silos
- Pi- Fermentation Systems
- Glycol re-boilers
USED IN PROCESSES
- Aseptic
- Food
- Dairy
- Beverage
- Pharmaceutical
- Applications where contamination in unacceptable.
The VAC-SAF Disk Components
VAC-SAF TM Rupture disks consist of three main parts:
A perforated and slotted metal section.
A Fluropolymer seal with integral Fluropolymer button.
A Fluropolymer slit cover between the Fluropolymer seal and the metal section prevents damage to the seal by the slits in the metal section.
Rupture Disk (Bursting Disc) Types DKB & VKB
Features
- Unique two-way acting disks prevent vessel damage from implosion under vacuum or over pressure
- Available in sizes 50 mm to 200 mm
- No-Vacuum relief pressures available from 110 mbar down to 10mbar
- Not for gas or liquid applications
- Disk offers smooth surface towards the process which prevents product accumulation and facilitates cleaning of the disk
- Asymmetric alignment pins in the Safety Head mate with locating holes in the rupture disk (bursting disc) for proper alignment and installation
- The standard material of the disks metal section is 316 SS. Consult BS&B regarding other materials, e.g. lnconel 600, Monel 400, Nickel 200 and Hastelloy C-276. The disk’s seal material is fluoropolymer.
Vacuum Relief
At the rated Vacuum relief pressure the disk’s seal separates from the perforated metal section to snap against knife blades located in the safety Head inlet , cutting the seal into three segments. The perforated metal sections remains intact and flow through the holes in the metal sections relieves the Vacuum condition.
Overpressure Relief
The disk relieves over pressure by opening fully along the radial slits in the perforated metal section.
Pressure Range for Vacuum and over Pressure overpressure relief for
Disk Types DKB and VKB at 72 ‘F |
| Disk Size (in) |
Vacuum Relief |
Overpressure Relief |
| Minimum |
Maximum |
Vacuum Relief Area(sq.in) |
Minimum |
Maximum |
| Wc |
Bar |
wc |
Bar |
PSI |
Bar |
PSI |
Bar |
| 2 |
7.5 |
0.019 |
44 |
0.110 |
1.50 |
18 |
1.240 |
170 |
11.720 |
| 3 |
6.5 |
0.016 |
30 |
0.075 |
3.57 |
16 |
1.100 |
170 |
11.720 |
| 4 |
5.5 |
0.014 |
30 |
0.075 |
5.93 |
13 |
0.900 |
119 |
8.210 |
| 6 |
5.5 |
0.014 |
30 |
0.075 |
12.30 |
13 |
0.900 |
90 |
6.210 |
| 8 |
5.5 |
0.014 |
20 |
0.050 |
18.50 |
7 |
0.480 |
55 |
3.790 |
Rupture Disk Types DKB & VKB
VKB Rupture disk and KB-C Safety Head with quick release hygienic fittings provides easy dismantling for routine maintenance. The 0-ring seal provides leak-tight connection.
Vacuum Relief
Burst Range
The Disks are available with a Burst Range of +/- 3.75 mbar for pressure up to 20 mbar and +/- 20% for higher pressures. All tolerances are included in the Burst Range.
Markings
A disk with vacuum relief pressure of 18 mbar will be shown on the disk tag as min 14.25 mbar to max 21.75 mbar
Operating Pressure
The system may operate up to 80% of the minimum of the marked Burst Pressure without affecting the service life of the disk.
Overpressure Relief
Manufacturing Range
The disks are available with a +/- 0.138 bar or 10% manufacturing range depending on the burst pressure.
Tagged Burst Manufacturing
| Pressure |
Range |
| up to 2.76bar |
+/-0.138bar |
| above 2.76 bar |
-10% |
Example:
A burst pressure of 4 bar is requested with a 10% manufacturing range. The values of the burst tests carried out during manufacture will be between 3.6 bar and 4 bar. The average of these test values will be marked on the disk tag.
Burst Tolerance
Tolerances are the maximum variation from the burst pressure shown on the disk tag.
Tagged Burst
Pressure (bar) |
Burst Tolerances |
| 0.41 -0.55 |
+/- 20% |
| 0.62 -0.83 |
+/- 15% |
| 0.90-1.17 |
+/- 10% |
| 1.24-1.72 |
+/- 7% |
| 1.79 and above |
+/- 5% |
Operating Temperature Range
Minimum -40’C to Maximum 80’C.
Rupture Disk Types P/DKB & P/ VKB
Highlights
- Unique two-way acting disks prevent vessel damage from light over pressure or implosion under vacuum
- Available in sizes 50mm to 200mm
- Rupture pressures available from 110 mbar down to 10 mbar
- Asymmetric alignment pins in the Safety Head mate with locating holes in the rupture disk (bursting disc) for proper alignment and installation.
- The standard material of the disks metal section is 316SS. Consult BS&B regarding other materials, e.g. lnconel 600, Monel 400, Nickel 200 and Hastelloy C-276. The disk’s seal material is fluropolymer.
- For gas or liquid applications
PRESSURE RANGE FOR LIGHT OVERPRESSURE AND VACUUM RELIEF FOR DISK TYPE P/VKB
AT 22 C |
| OVER PRESSURE RELIEF (MBARS) |
| DISK SIZE |
MINIMUM |
MAXIMUM |
RELIEF AREA (SQ.MM) |
| 2″ 50 mm |
18.75 |
110 |
967 |
| 3″ 80mm |
16.25 |
75 |
2303 |
| 4″ 100mm |
13.75 |
75 |
3825 |
| 6″ 150mm |
13.37 |
75 |
7935 |
| 8″ 200mm |
13.75 |
50 |
11936 |
How the System Works
Overpressure relief
At the rated burst pressure the disk’s seal separates from the perforated metal section to snap against knife blades, located in the Safety Head outlet, cutting the seal into three segments. The perforated metal section remains intact and flow through the holes in the metal section relieves the over pressure.
Overpressure Relief
Burst Range: + /- 3.75 mbar for pressure up to 20 mbar and +/- 20% for higher pressures. All tolerances are included in the Burst Range.
Markings
A disk with a marked burst pressure of 40 mbar will be shown on the ,disk tag as Min. 32 mbar Max. 48 mbar
Operating Pressure
The system may operate up to 80% of the minimum of the Burst Range without affecting the service life of the disk.
Operating Temperature Range
Minimum -40oC to Maximum 80oC
Vacuum Relief
The disk may be used also to relieve vacuum depending on specific requirements.
Safety Head Insert Types KB-7R & PKB-7R
- Quik-Sert reduces diameter safety head fits inside the studs of two companion flanges
- Asymmetric alignment pins in the Safety Head mate with locating holes in the rupture disk (bursting disc) for proper
alignment and installation
- The inlet and outlet of the Safety Heads is held together by side lugs
- Standard materials are 304 SS and carbon steel. Consult BS&B Safety Systems for other materials
- Knife blade material is 301 SS
The dome of the disk is protected by the Safety Head.
| SAFETY HEAD SPECIFICATION |
| RUPTURE DISKNOMINAL |
PN 10 |
ANSI 150 |
| A OUTSIDE DIAMETER |
B OVERHEIGHT |
A OUTSIDE DIAMETER |
B OVER HEIGHT |
| 2″ 50mm |
107mm |
46.5mm |
102.0mm |
46.5mm |
| 3″ 80mm |
142mm |
47.5mm |
133.0mm |
47.5mm |
| 4″ 100mm |
162mm |
59.0mm |
171.0mm |
59.0mm |
| 6″ 150mm |
218mm |
66.0mm |
219.0mm |
66.0mm |
| 8″ 200mm |
273mm |
71.5mm |
276.0mm |
71.5mm |
Safety Head Hygenic Types KB-C & PKB-C
- Hygienic fittings permit quick installation or dismantling
- Ring seal provides leak tight connection
- Asymmetric alignment pins in the Safety Head mate with locating holes in the rupture disk (bursting disc) for proper alignment and installation
- The knife blade material is 301 SS
- Safety Head material 300 series stainless steel
| SAFETY HEAD SPECIFICATION |
| RUPTURE DISK NOMINAL |
A OUTSIDE DIAMETER |
B OVER ALL HEIGHT |
HYGIENIC FITTING SIZE |
| 2″ 50mm |
90.4mm |
76.2mm |
3″ 76.2mm |
| 3″ 80mm |
118.8mm |
76.2mm |
4″ 101.6mm |
| 4″ 100mm |
166.6mm |
101.6mm |
6″ 152.4mm |
| 6″ 150mm |
217.4mm |
101.6mm |
8″ 203.2mm |
| 8″ 200mm |
268.2mm |
114.3mm |
10″ 254.0mm |
