Densit Aps is the leading provider of Engineered UHPC (Ultra High Performance Concrete) Solutions to the upstream oil and gas industry. From initial design to final abandonment, our engineered UHPC solutions offer added value to your assets.

  • Design life extension – engineering through implementation
  • Structural strengthening services
  • Well refurbishment services
  • Plugging and abandonment services
  • UHPC in platform designs

From initial inspection, through engineering to the final implementation, Densit UHPC solutions have proven to be an extremely cost effective means of upgrading offshore facilities, solving fatigue life and over-stress problems.

Extending the service life of your assets does not only release additional revenues and increase "return on investment", it also defers the huge cost of abandonment. At Densit, we are prepared to take on your challenges. From conceptual design to execution – your problems are our commitment.

EXTREME PROPERTIES OF DUCORIT UHPC MATERIALS

Densit has developed a portfolio of non-shrinking UHPC materials specifically designed for oil and gas industry applications. The Ducorit range of UHPC materials exhibit extreme mechanical properties, often surpassing material requirements in engineering designs.

The strength characteristics exhibited by Ducorit® exceed those of conventional materials by a factor of 5 to10.
Grouting is usually carried out from a workstation on the platform where mixing and pumping grout takes place.
Densit® reinforcement technology is currently used in a number of applications including offshore grouting, wear linings, security barriers, industrial flooring and concrete repairs.

Important properties of Ducorit UHPC materials include:

  • Underwater operations – the high viscosity and inner cohesion of Ducorit UHPC materials prevent “washing out” of particles, separation or mixture with water when cast underwater.
  • Strength Development – Ducorit UHPC materials develop a significant early strength, reaching 50% of the final strength within 24 hours at 20°C
  • Fatigue – the fatigue strength of Ducorit UHPC material to increase the tensile and bending strength, leading to higher ductility and fracture energy
  • Fibre reinforcement – steel fibres can be incorporated into Ducorit UHPC materials to increase the tensile and bending strength, leading to higher ductility and fracture energy

STRUCTURAL STRENGTHENING AND REPAIR

Strengthening of offshore structures may be required or just desirable for a number of reasons, e.g. additional loading or structural damage of existing platforms or low installation weight for new structures. The unique mechanical and physical properties of the Densit UHPC materials provide a cost-effective solution for structural strengthening.

Structural strengthening of selected members, joints or annuli can result in e.g. reduced number of braces necessary or shorter interface length of pile-sleeve connections.

WELL ABANDONMENT WITH A CONSCIENCE

Traditionally depleted wells have been plugged using conventional oil well cements. This provides a simple and inexpensive solution but one that is often prone to failure due to the poor quality of both the cement materials and cementing process. Left unattended for many years well fluids can permeate through the cement plug and contaminate the surrounding environment.

Densit plugging and abandonment services are carried out in an expedient rigless operation. The unique mechanical and physical properties of our innovative range of UHPC materials provide robust and durable well plugging for generations to come.

WELL REFURBISHMENT SERVICES

After many years in service, often in very hostile environments, corrosion becomes an increasing threat to the integrity of the well. Unattended corrosion may lead to leaking and/or collapse of well strings resulting in lost production revenues and significant costs for re-establishing the well.

Densit UHPC based well integrity solutions offer in conjunction with structural reinstatement of the well string, effective protection against corrosion, without affecting production rates.

Down-hole inspection, plugging and installation of Densit UHPC materials are expediently carried out for a wide range of well configurations and even when the annuli are very narrow.

Over the recent years, Densit has been involved in corrosion protection and structural strengthening of highly corroded wells both off- and onshore.

CORROSION PROTECTION

Corrosion has become an increasing threat to the integrity of offshore structures including pipelines, casing, well casings and tubings world wide. Failure of all or part of these structures may in many cases have disastrous consequences and results in lost production revenues and significant costs for re-establishing the structure.

NO CHLORIDE DIFFUSION

Densit® UHPC materials offer a durable and cost effective solution for corrosion protection due to its very low chloride diffusion being in the order of 0.6×10-13 m2/sec, which is in the order of 1/50 of other cementitious materials. Low shrinkage of the grout ensures that it remains in physical contact with steel and concrete surfaces after curing.

In addition to the unique corrosion protection offered by Densit® UHPC materials, the high strength and the high bonding between the steel and concrete also leads to improvements in the structural integrity of the structure.

Densit® UHPC materials have been applied for corrosion protection of:

  • Piled jetty structures
  • Conductors
  • Sump caisson
  • Steel piles