Emission Covers
The Primary Emission Barrier
Emissions of volatile organic compounds (VOC) from penetrations in external floating roofs are contribute significantly to the total emission on a tank storage facility, For operational reasons these openings cannot be avoided and should be covered in the pursuit of our zero emission goal.
To bring emissions down to acceptable levels, these openings can be best sealed with our emission covers. We have solutions for support legs (leg seals and leg socks) and for avoiding emissions on slotted gauge poles (guide pole cover or guide pole sleeve)
These combined solutions significantly reduce the emission from external floating roof tanks, without having to revert to expensive emission control measures.
Truly Circular
GUIDE POLE COVERS
GUIDE POLE SLEEVES
LEG SEALS
LEG SOCKS
Our Leg socks consist of flexible, hydrocarbon resistant material, covering the top of the leg. They are designed of PTFE material with very high resistance against a wide range of liquids and is suitable for the most demanding environmental conditions. The sock is fully closed for emission and rain water by a stainless steel clamp.
In the following tables we have provided more specific information relating to the materials and product data of our Leg socks.
Material
| Fabric | Plain weaved glass |
| Coating | PTFE |
| Clamp | SS 304 (1.4301) |
Leg sock product data
| Width [mm] | Length [mm] |
| 106 | 1,650 |
| 110 | 1,425 |
| 121 | 1,000 |
| 135 | 405 |
| 136 | 400 |
| 140 | 1,650 |
| 160 | 1,050 |
| 166 | 625 |
| 203 | 1,220 |
| 203 | 305 |
| 210 | 1,350 |
| 220 | 1,650 |
| 260 | 1,350 |
| 260 | 1,550 |
| 360 | 1,000 |
Other dimensions upon request
Gauge Pole Covers greatly reduce hydrocarbon vapours from slotted guide pole covers in Aboveground Storage Tank (AST). Tank owners benefit by reducing product emissions and meeting environmental regulations.
Gauge Pole Covers are manufactured from a unique double fabric, with uniformly resistant PTFE on the inside and wather resistand Silicone on the outside. The optional Transition Box seals the cover at the EFR guide pole box.
Cover material
- Gauge pole fabric covers consist of 2 materials that combine unique characteristics. Inner layer is highly aromatic resistant PTFE and the outer layer is fire and UV resistant Silicone.
- This makes the cover suitable for all possible stored products including 100% aromatics under the most harsh weather consitions
Transition box material (if required)
- The (optional) transition box material is SS 304 L
- The Transition box split parts will overlap each other with a minimum of 2”. This will ensure that the transition box in combination with silicone has an optimal sealing.
Base fabric
| YARN | Warp | EC9 | 136 tex | ± 5% | DIN 53830-3 |
| Weft | EC9 | 136 tex | ± 5% | ||
| Thread count | Warp | 19,0 | 1/cm | ± 5% | DIN-EN 1049-2 |
| Weft | 13,0 | 1/cm | ± 5% | ||
| Weight | g/m2 | ± 5% | DIN EN 12127 | ||
| Weave | Satin | ISO 9354 | |||
| Temp resistance | 550 oC |
Coated fabric
| Tensile strength | Warp | <3.100 | N/5cm | DIN EN ISO 13934-1 | |
| Weft | >2.200 | N/5cm | |||
| Weight | g/m2 | ± 5% | DIN EN 12127 | ||
| Thicknes | 0,4 | Mm | ± 10% | DIN EN ISO 5084 | |
| Temp resistance | 250 oC | ||||
| Internal coating | PTFE | ||||
| External coating | Silicone |
A leg sleeve consists of two half-scales that are clamped around a leg. The inside of the seal is fitted with gasket profiles, an engineered interlock completes the components. Stainless steel hose clamps are used to fit the two scales together to form a seal. The high position hole is sealed with a top sleeve. This combination makes a completely sealed support leg. This configuration has the additional advantage that the leg pin is kept in place and crevice corrosion avoided
EPDM withstands both ozone and UV radiation well, and has a high chemical and temperature tolerance, as well as allowing effective processing during production.
Material
| Leg seal | EPDM 60 Shore A rubber (hydrocarbon, chemical and ozone resistant and weather-proof) |
| Hose clamps | SS 304 (1.4301) |
| Pin hole plug (optional) | EPDM 60 Shore A rubber (hydrocarbon, chemical and ozone resistant and weather-proof) |
Leg seal product data
| Leg size | Sleeve size | Upper inside diameter [mm] | Lower inside diameter [mm] | Height [mm] |
| 2½” | 3” | 75 | 90 | 200 |
| 3½” | 75 | 102 | 200 | |
| 3” | 3½” | 89 | 102 | 200 |
| 4” | 90 | 115 | 165 | |
| 4” | 90 | 115 | 200 | |
| 4” | 90 | 115 | 225 | |
| 4” | 5” | 115 | 145 | 165 |
| 5” | 115 | 145 | 225 | |
| 5” | 115 | 145 | 242 |
Pin hole plug product data
| Hole size [mm] | Diameter [mm] | Height [mm] |
| 30 | 70 | 29 |
| 35 | 70 | 29 |
| 38 | 70 | 29 |
| 42 | 70 | 29 |
| 45 | 70 | 29 |
| 50 | 70 | 29 |