Monopiles and Transition Pieces
Sif Group is one of the first manufacturers of monopiles worldwide. With more than 20 years’ experience in the offshore wind industry, we have already produced over 2,500 monopiles in our plants in Roermond and Maasvlakte 2 in Rotterdam.
The Monopile
The lengths and diameters of monopiles have increased dramatically in recent years. Whereas we used to manufacture monopiles with a 4-metre diameter and a length of 40 metres, we now produce monopiles that are some 11 metres in diameter and 120 metres in length. Our production location on Maasvlakte 2 has been expanded to meet the new requirements. We can now produce up to 500,000 tonnes of steel per year. These ‘XXXL monopiles’ are given a protective coating and form a strong foundation for larger offshore wind turbines, even for wind farms in remote areas in deep waters.
Sif is known for its reliability and high quality. We have never received a fine for late delivery of any of our 2,500 monopiles. With a production speed of 4 - 5 monopiles per week and a central location in Europe, we are the ideal partner for offshore wind projects.
The technical specifications of a Sif Group monopile are:
- Diameter: 11,0 meters
- Weight: 2500 tonnes (can be heavier on request)
- Length: 120 meters
- Wall thickness: 160 mm
- Production speed: 4-5 per week
Transition pieces
A transition piece traditionally connects a monopile with a wind turbine tower. These pieces are usually connected together using a flange-bolt connection. Together with Smulders, our partner in Belgium, we have already supplied over 2,000 transition pieces. Our customers value our experience and return to us, time after time.
Sif produces the primary steel for the transition pieces in Roermond, before transporting them to Smulders in Hoboken (Belgium) for further finishing. The final product is then shipped to Maasvlakte 2.
The technical specifications of a Sif Group transition piece are:
- Diameter: 8,45 meters
- Weight: 950 tonnes
- Length: 32 meters
- Wall thickness: 160 mm
- Production speed: 4-5 per week
TP-Less monopile
The demand for extended monopiles, otherwise known as TP-Less monopiles is increasing. Globally, Sif has produced the most TP-Less monopiles. We collaborate with Smulders for welding attachments and the secondary steel package.
The TP-Less monopile offers space for innovations including the Skybox and internal platforms that can replace the boat landing. These monopiles are often 20 to 30 metres longer than traditional monopiles and save on weight by eliminating the skirt, the overlength required to move a transition piece across the monopile.
Value Engineering
In the earlier project development phases, we help devise an ideal foundation solution for wind farms. Our value engineering expertise helps with respect to cost-effective design. Together with KCI The Engineers, we advise on the optimal layout of cans and cones for the most efficient production. This results in a manufacturable and cost-effective foundation.
Our value engineering offers customers the opportunity to consider the advantages and disadvantages of the various options at an early stage. Together with our subsidiary, KCI The Engineers, we offer extensive knowledge and experience in the design and calculation of offshore foundations.
Welding Technology
Our technical knowledge enables us to communicate efficiently with customers. We have a wealth of experience in welding high-quality, incredibly strong steel alloys for harsh and cold conditions.
At Sif, we are proud of:
- Internal training and qualifications for all welders
- Our own design of welding machines
- Optimised welding techniques
- Many years of rolling expertise and the capacity for cold rolling the highest rollable wall thicknesses
- 75 years’ experience
Sif's key data production site
