SIRIUSRiser Tensioner

In development · design targets below
SWL 350 / 500 t (concept) · stroke 3.0–12.0 m (target)

Backup riser tensioning for drilling and workover. SIRIUS is a concept selected around the operating window, riser configuration and required tension capacity.

Discuss SIRIUS How tension is held ↓
Specifications on this page are design targets
and subject to change
Concept architecture

How tension is held

Hydraulic cylinders work against nitrogen accumulators: as the vessel heaves, the cylinders stroke and oil shifts into the gas volume — riser tension stays inside a band across the stroke.

Read the riser-tensioning guide ↗
SIRIUS — TENSIONING ARCHITECTURECONCEPT — NOT A BUILD DRAWINGELEVATION — CONCEPTDECKvessel heave ±RISER — held in tensiontensioner ringtensioner cylindersNITROGEN ACCUMULATORSgas over oil — the springN₂oilN₂oildamping — manually setwellhead / seabedRISER TENSION vs STROKETENSION BANDNOMINAL TENSIONtension across the strokeriser tensionstroke — as the vessel heavesconcept — no scalevessel heaves → cylinders stroke → oil into N₂ → tension held in the bandoilnitrogen / bandstructureSTATUS: IN DEVELOPMENTNOT A BUILD DRAWINGconcept — proportions are illustrative SIRIUS — TENSIONING ARCHITECTUREELEVATION — CONCEPTDECKvessel heave ±RISER — held in tensiontensioner ringtensioner cylindersNITROGEN ACCUMULATORSgas over oil — the springN₂oilN₂oildamping — manually setwellhead / seabedRISER TENSION vs STROKETENSION BANDNOMINAL TENSIONtension across the strokeriser tensionstroke — as the vessel heavesconcept — no scalevessel heaves → cylinders stroke → oil into N₂ → tension held in the bandoilnitrogen / bandstructureSTATUS: IN DEVELOPMENTNOT A BUILD DRAWINGconcept — proportions are illustrative

Concept architecture — SIRIUS is in development; configurations are being defined. The diagram shows the tensioning concept, not a build drawing.

Backup tensioning, controlled compensation

SIRIUS is a tensioning concept for drilling and workover operations where backup riser tensioning and controlled compensation are required — long-stroke, topside, with manually set damping.

  • Backup riser tensioning
  • Workover compensation duties
  • Long-stroke — targets to 12.0 m
  • Manual damping
  • Topside installation
In development · design targets subject to change
350 / 500 t
SWL — concept points
3.0–12.0 m
Stroke — design target
Manual
Damping
Topside
Form
Selection

Sized from the operation, not a catalogue

01

Operating window

The sea states and durations the operation must ride out set the compensation duty the tensioner has to carry.

02

Riser configuration

The riser string and its interfaces define the geometry and stroke the unit works across — design targets run long, 3.0 to 12.0 m.

03

Required tension capacity

The tension the riser must hold sets the capacity point — the concept is defined at 350 and 500 t.

When SIRIUS is the right choice

Drilling or workover operations that need backup riser tensioning and controlled compensation.

Engineering check

Send SWL, stroke, sea state, payload and operation sequence — the team reviews the case and confirms the practical product fit before any hardware is discussed.

Status

SIRIUS is in development. The capacity points and stroke range on this page are design targets, and configurations are being defined against real operations — early input shapes the first units.

In developmentBackup tensioningWorkover compensation
500 t / 8 m tensioner for oil drilling on the workshop floor, ready for delivery
Proof · delivered hardware

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.

Go deeper

SIRIUS’s lane in the Knowledge Hub

KB · OPERATIONS

Riser tensioning

Why risers are tensioned, what the duty looks like — and where backup capacity fits.

Read → KB · PLANNING

Weather windows

How operating windows are screened and what they mean for equipment selection.

Read → KB · SELECTION

Heave compensator selection

The full product family and a practical selector for your case.

Read →
The product family

Where SIRIUS sits

02CYGNUSSWL 12.5–10,000 t
stroke 1.0–6.0 m 03ANTARESSWL 30–4,000 t
stroke 2.5–8.0 m 06SIRIUSSWL 350 / 500 t (concept)
stroke 3.0–12.0 mYou are here 07CONSTELLATIONLift screening
DNV-RP-N103 Compare all systems →
Frequently asked questions

SIRIUS, answered

When is SIRIUS the right choice?
When drilling or workover operations need backup riser tensioning and controlled compensation. For lifting operations, the heave compensator family — RIGEL, CYGNUS, ANTARES and VEGA — is the right starting point.
How is SIRIUS sized?
SIRIUS is selected from the operating window, riser configuration and required tension capacity — the concept is defined at 350 and 500 t with strokes from 3.0 to 12.0 m.
SIRIUS is in development — what does that mean for my project?
The capacity points and stroke range on this page are design targets. Send the operating window, riser configuration and required tension, and the team will review the case and return the recommended path and next engineering step.
Early engagement

Discuss SIRIUS.

SIRIUS is in development — early input shapes the first units
SIRIUS configurations from approximately USD 150,000

Indicative only — final pricing depends on tension, stroke and classification requirements.

Share the operating window, riser configuration and required tension capacity. Norwegian Dynamics will review the case and return the recommended product path and next engineering step.

post@nodynamics.com · +47 9664 7886
Specifications are design targets

Concept points 350 / 500 t.
Design targets 3.0–12.0 m.
PDF, CAD, spreadsheet, ZIP or OrcaFlex — up to 5 files, 15 MB in total.

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Discuss SIRIUS