LPG Vessel and pipe work installation and maintenance

Double wall pipework for emergency generator systems

Retractable primary pipes

The primary pipes, supplied in coils of 50 or 100 m are installed in secondary ducts supplied in coils of 50 m and 76 m. Ducts can be connected to each other when longer lengths are required.
According to the duct’s diameter, multiple primary pipes can be inserted in one duct (2 to 3 in the SP3501 and up to 4 in the SP6001 duct). The primary pipes remain retractable without excavation.
Manually installable couplings with swivelling nuts and BSPT adaptors are supplied to complete the pipe work on site. ‘EASY FIT’ pipe entry fittings combined with specific sealing donuts ensure liquid tightness in the tank chamber and when passing the wall or the floor slab of the technical room.


  • Complies with EN14125 – A1
  • Secondary contained pipework
  • Manually installed couplings
  • Quick and easy installation
  • Installed in continuous runs
  • Primary pipes remain retractable
  • Multiple primary pipes fit in secondary duct
Multiple Pipes can fit in a secondary duct and are still retractable
Example of a duct passing through a wall

Double wall pipework for fuel furnaces & emergency generator systems

Computer datacentres rely on complex power backup systems involving diesel-generator units. Double wall FOGS pipe systems are being installed between tanks, pump room and the generator.

Several double wall storage tanks, each with a capacity ranging between 100 m³ to 120 m³, are buried in the vicinity of the building. Liquid tight access chambers are installed on each manway.

A typical datacentre has an underground fuel storage capacity ranging from 300 m³ to 800 m³ to feed the generator units. The remote fill points, installed in a liquid tight chamber, centralize the 4” fill lines (one to each of the 4 underground tanks as well as a 2 1/2” lubricant oil delivery line and a 2 1/2” used lubricant oil suction line.

All pipe runs are double wall, flexible pipework.
The feed & return line from the tank to the generator room runs into secondary ducts. Between 1 to 4 primary lines can be inserted into secondary ducts with diameters 3 1/2” and 6”.

Both primary pipes and secondary ducts are laid in continuous runs, without buried inaccessible joints. At both ends, the primary pipes are sealed with the secondary duct by means of flexible boots and special donuts. The boots are equipped with a valve for eventual continuous monitoring of the interstitial space.


For more in-depth information, please click on the image below to download the datasheet:

FOGS - Double wall pipework for emergency generator systems
FOGS - Double wall pipework for emergency generator systems