Thief Hatch (Weight loaded)
Model No: 240
ERGIL Storagetech™’s Model 240 Thief Hatch offers protection against pressure and vacuum.
Within the cover are a static pressure seal, and a weight-loaded vacuum pallet and diaphragm assembly. The pressure and vacuum settings can be selected from a standard list.
As excessive pressure builds up in the storage tank or vessel the hinged hatch cover lifts, breaking the seal and allowing excess pressure to dissipate into the atmosphere. It closes under gravity when the pressure has returned to normal.
If the tank is subjected to negative pressure, the vacuum pallet and diaphragm assembly opens and allows air to be drawn into the vessel. The diaphragm closes when a positive pressure is established.
The unit must be installed on a flange at the top of the tank in the horizontal plane. It is possible to access the tank for gauging and sampling by fully opening the hatch.
Setting Range
| Pressure & Vacuum | : Weight-loaded +2.0 mbar and +25 mbar. (+0.8 inch W.C and +10 inch W.C) |
| Ambient temp | : Weight-loaded -20°C to +60°C |
Construction
| Standard sizes | : 2” to 12” 50 to 300mm |
| Flanges | : API Class 150 RF, DIN PN16 |
| Body | : Carbon steel, stainless steel, or aluminium |
| Seals | : Nitrile, Teflon, and Klingrit |
| Pallet | : Stainless steel AISI 304 |
| Weights | : Carbon steel, stainless steel, or aluminium |
| Paint finish |
1-) Powder Coating, Colour RAL 9006 2-) Epoxy Paint, Colour RAL 9006 3-) Customer Specification |
Design & Manufacturing Specifications
The integrity of the seal is tested for leakage in accordance with API Standard 2521 - Use of Pressure-Vacuum Vent Valves for Atmospheric Loss.
The size of the vent should be calculated in accordance with API Standard 2000 (ISO 28300) - Venting Atmospheric and Low-Pressure Storage Tanks or other international standards.