Tensioner
In development · design targets belowA general-purpose family of tensioners that hold a set tension while the vessel moves, from backup riser tensioning to workover. Each unit is selected around the operating window, what it holds and the tension it must keep.
and subject to change
How tension is held
Hydraulic cylinders work against nitrogen accumulators. As the vessel heaves, the cylinders stroke and oil shifts into the gas volume, so the tension stays inside a band across the stroke. The diagram shows one of its duties: a riser held in tension.
Read the riser-tensioning guide ↗Concept architecture, shown on a riser. SIRIUS is in development and configurations are being defined; the diagram shows the tensioning concept, not a build drawing.
One tensioner family, many duties
SIRIUS is a family of topside tensioners with manually set damping and strokes from 1 to 12 m. It holds a set tension on what the vessel is connected to while the vessel moves: a riser that needs backup tensioning, a workover string, or another line that must stay in tension.
- General-purpose: risers, workover strings and other lines
- Backup riser tensioning and workover compensation
- Stroke from 1.0 to 12.0 m
- Manual damping
- Topside installation
Sized from the operation, not a catalogue
Operating window
The sea states and durations the operation must ride out set the compensation duty the tensioner has to carry.
What it holds
The riser, string or line and its interfaces set the geometry and the stroke the unit works across; design targets run from 1.0 to 12.0 m.
Required tension capacity
The tension to be held sets the capacity; the family is planned from 5 to 5,000 t.
When SIRIUS is the right choice
When something connected to a moving vessel has to be held at a set tension: backup riser tensioning, workover compensation and other constant-tension duties.
Engineering check
Send the tension, stroke, sea state and operation sequence. The team reviews the case and confirms the product fit before any hardware is discussed.
Status
SIRIUS is in development. The capacity and stroke ranges on this page are design targets, and configurations are being defined against real operations. Early input shapes the first units.
The hardware heritage is real.
SIRIUS the product is in development; the tensioner hardware behind it is not. Our team has delivered long-stroke tensioner systems before, including the 500 t / 8 m drilling tensioner shown here on the workshop floor.
SIRIUS’s lane in the Knowledge Hub
Riser tensioning
Why risers are tensioned, what the duty looks like, and where a backup tensioner fits.
Read → KB · PLANNINGWeather windows
How operating windows are screened and what they mean for equipment selection.
Read → KB · SELECTIONHeave compensator selection
The full product family and a practical selector for your case.
Read →Where SIRIUS sits
SWL 12.5–10,000 tstroke 1.0–6.0 m 03
SWL 30–4,000 tstroke 2.5–8.0 m 06
SWL 5–5,000 tstroke 1.0–12.0 mYou are here 07
Lift screeningDNV-RP-N103 Compare all systems →
SIRIUS, answered
When is SIRIUS the right choice?
How is SIRIUS sized?
SIRIUS is in development: what does that mean for my project?
Discuss SIRIUS.
Indicative only: final pricing depends on tension, stroke and classification requirements.
Share the operating window, what the unit has to hold and the tension it must keep. Norwegian Dynamics will review the case and return the recommended product path and next engineering step.