In the central part of the North Sea, near the Danisch/Norwegian border, is the Hejre field. The field is located at a water depth of approximately 70 meters and covers an area of approximately 30km2. The Hejre field contains two thirds oil and one third gas. The development of this field is the largest oil and gas project in the Danish sector. The production from the Hejre field is expected to total about 15 million m3 of oil and about 10 billion m3 of gas during the term of the project. The production start-up is scheduled for 2016.
Offshore production requires onshore expansion
The Hejre development will be connected to the existing infrastructure in the North Sea through separate pipelines for oil and gas, providing secure and reliable product logistics from the offshore area. However, the facilities at the onshore oil and gas terminal in Fredericia will be modified and expanded in connection with the commissioning of the Hejre-field. In 2015, the extended terminal has to be ready to receive and handle the additional oil and gas from the Hejre field.
The expansion of this terminal includes the establishment of gas processing plants and storage facilities for liquefied propane and butane with eight bullet tanks. The tanks will be used to store butane and propane gas prior to shipping, as well as for temporary storage of ‘off-gas’ – i.e. gas not compliant with the propane and butane specifications. The bullet tanks are not average tanks, these were huge! Not only in weight (325,5 tonnes including transport saddles), but also in size. The tanks, manufactured in Willebroek (Belgium) are measuring 38,54 meters in length, 8,43 meters in diameter and have a volume of 1.850 m3. So, how to get these giants from Belgium to Denmark? Royal Wagenborg knew the answer on this project comprising the transport of eight giant bullet tanks to the terminal in Denmark where they had to be placed on an unconventional sand bed foundation. A perfect challenge to demonstrate Wagenborg’s expertise on the field of ‘factory to foundation logistics’.
During transport with SPMTs, the trailer operator is walking along the entire transport route holding the remote control panel. No problem for a single short distance transport, but for longer distances engineers, HSEQ members and SPMT trailer operators of Wagenborg developed a safe and efficient solution: the SPMT support platform. The SPMT support platform is a folding platform, assembled to the power pack unit. The platform,... Next ›
The journey by sea
At the manufacturers’ site in Willebroek, the tanks were loaded onto barges by means of a RORO (Roll on Roll off) operation. From here on the tanks set sail towards the port of Rotterdam, where the bullet tanks were loaded onto our Self Propelled Modular Trailers (SPMT) by means of the sheerleg ‘Matador 3’ and temporarily stored onto steel supports. The sea transport to Denmark was carried out by a heavy lifting ship. In the Danish port the bullet tanks were discharged by the vessel’s own cranes onto our SPMT’s and temporarily stored, waiting for their final transport and installation at the oil terminal 6.5 kilometers ahead.
Driving through narrow streets
Since the transport had to cross a town between the port and the jobs site, the route was accurately analyzed by Wagenborg.
Every traffic light, street light, road sign, tree and any other obstruction was documented and identified for (temporary) removal. This was as much of a challenge as it was an opportunity to show how well prepared and professional this part of the project was executed. The optimum transport route has been assessed in cooperation between Wagenborg, our customer and local authorities. Subsequently all 8 bullets were transported through town in sets of 2 pieces on alternate days. A real impressive sight to see the bullets drove slowly and carefully through the narrow streets of this town. A route which required lots of calculations and engineering for the right SPMT configuration. But with this perfect preparation, excellent crews and with the assistance of the local authorities the entire operation went perfectly.
For the transport in Denmark, Wagenborg used a
double connected 16 axle line Scheuerle SPMT.
The Scheuerle SPMTs that were used were 4 x 6 axle lines and 2 x 4 axle line, 32 axle lines in total. Each 4-axle line unit and each 6-axle line unit comes with 4 drive axles, a total of 24 drive axle on this transport combination. The SPMTs were equipped with 2 power packs of 350 kW each. As a safe rule of thumb it can be stated that every 10 axle lines require approximately 75 kW. With 32 axle lines this transport would require a minimum of 240 kW.
The actual combination used 2 PPUs of 350 kW each, more than sufficient for its purpose. However, nothing was left to chance. As part of the riskanalysis Wagenborg assumed a worse-case scenario where one PPU would fail and climbs during the route would have to be made with one PPU.
Upon arrival at the site location the transporters and the bullets faced a 10% slope leading up to the final resting place of the bullets. Wagenborg’s engineers determined that for this last stretch more than sufficient
tractive effort was available to make this climb safely.
Operational detail, as can be seen on the picture above, during the climb, the transporter deck was lowered in the front and raised in the rear to offset some of the 10% incline.
Lifting the tanks to their final position
On the terminal, where the bullets had to be installed, Wagenborg mobilized two of their large crawler cranes along with all the required rigging materials and lots of crane mats to perform a tandem lift. The 400 ton Liebherr LR1400 crawler crane and the 350 ton Demag CC2200 were both equipped with a main boom and superlift ballast. The Demag CC2200 was set to a lift radius of 19 m which resulted in a lifting
capacity of 188 ton. The 400 ton Liebherr lifted its end of the bullets at 20 m radius which gave it a capacity of 177 ton. The combined capacity was therefore 365 ton to lift the bullet tank, weighing 301,5 ton, to its foundation.
For the lifting operation the SPMTs maneuvered the bullets in front of the foundation where the rigging was attached. The bullets were belly slung with nylon belts to facilitate a quick turnaround. The rigging layout was cleverly designed in such a way that it could all be hooked up and attached at ground level without the cumbersome use of man baskets and/or man lifts. Subsequently the bullets were lifted from their saddles to sufficient height to clear the foundations and sand beds and both cranes walked to the far end of the sand bed foundation to lower the first bullet in its final place. The carefully laid out crane mats, hundreds of them, ensured that the ground pressure imposed by the cranes never exceeded 10 ton/m2. Worth mentioning is the fact that the crane operator in the Demag crane was performing the lift blind, as he was working from behind a foundation wall that completely blocked his view. Dry runs and clear communication between all Wagenborg crew members made even this part of the project go smoothly. At a rate of two bullets per day, this part
of the project was completed in just four days.
Modifications and smart thinking
To make this project a bit easier to execute, the engineering department at Wagenborg put their heads together and designed a few add-ons on for the transporters. First they designed a fold-up platform for the PPU’s to allows the SPMT operator to stand on it during transportation. In tight turns he can step off the platform, fold it up and continue the transport.
The other smart solution form the Wagenborg engineers was a mini superlift tray. Nothing out of the ordinary you may think, but it is more the application than the manufacturing. This mini superlift tray is yet another sign of how well prepared this project was. Once the bullets
are set down, the superlift tray also sits on the ground. It would take multiple trips back and forth to bring all superlift ballast back to its origin. The mini superlift tray is part of the original superlift tray during the lifting operation. When the bullet is disconnected, the crane rotates 180 degrees and picks up the mini superlift tray from the original superlift tray with 100 ton of the total of 190 ton, the crane once again rotates 180 degrees back and connects the original superlift tray. Now that the crane carries 100 ton in its main hook, it can boom down sufficiently to let the original superlift tray float and the entire superlift arrangement is taken to the its origin in one shot.
A well planned and well executed project.