Our proprietary simulation technology predicts variations in downhole pressure ("surge & swab") and other parameters, induced by waves during drilling and completion operations carried out from floating rigs. This helps managing risks related to breaching well pressure margins or damaging downhole tools as well as reducing non-productive time.


- Reduce risk through early warning for possible mud losses, wellbore ballooning and kicks

-  Reduce costs by tripping faster (optimized tripping speed throughout the well)

- Reduce NPT by optimizing heave limits based on properties of YOUR well




Less mud losses means lower drilling costs

Less waiting on weather in offshore drilling

Safer drilling operations with less emissions

Surge & swab simulation software

Surge & swab simulation services



When the drill pipe is put in slips during break-out or connection of the next stand, the topside heave compensation of the drill string is disabled. The whole drill string starts to move up and down with the rig.


When the drill string moves downwards, there is a sudden increase in downhole pressure ("surge"), which can surpass fracture pressure and severely damage the well.


When the string moves upwards, there is a sudden decrease in downhole pressure ("swab"). If downhole pressure falls below the pore pressure it causes a well to start producing, which may lead to kicks and in the absolute worst case scenario a blowout.



Our advanced simulation software is able to calculate anticipated bottom-hole surge & swab during drill pipe connections based on such inputs as rig type, drilling fluid data and well trajectory and geometry. Utilizing statistical data analysis for weather on a drilling location, we are able to provide an estimate of surge & swab pressure margins for your well.

Using our surge & swab simulations it is possible to determine a precise dynamic rig heave limit based on how much surge & swab your well can tolerate, not how much heave and waves the drilling rig you use can tolerate. This information will make you prepared for mud losses or kicks and can save weeks of NPT.

Surge & swab simulations and operability studies are available now – get in touch with us for an offer!


“No-one is offering a comparable commercial solution today, either for pre-planning or real time”

– Major operator company



Surge & swab "roadmap" for well planning

- Precise calculations of surge & swab on drill pipe connections and/or rig heave limits for different parts of your well


24/7 operational support

- Rolling rig heave limit forecast for data-driven decision support, minimizing the risk of breaching well pressure margins


Operability studies for floating rigs in harsh weather


Cost-efficient surge & swab simulation services





Get in touch with us if you want full text of a paper or presentation!

Surge & swab calculations delivered to Odfjell Drilling in March-April 2020-

- We performed a surge & swab study on different heave compensation methods. The study contained 150 different simulations highlighting the differences in the methods. Technical report together with interactive plots from the simulations. The study led to interesting input for the client and their products!

Surge & swab and flow calculations delivered to Shell in January-February 2020

- Downhole surge & swab calculations brought on by rig heave during completion operations. We also calculated the flow passing a packer element for different heave conditions. The work led to updated heave limits for the operation. Faster and safer operations!

Rig operability study, delivered to OMV Norway in September 2019

- We performed operability calculations for two different rig types in Barents Sea, Norwegian Sea and North Sea. The calculations were based on fixed rig heave limits (conventional method) and on dynamic limits, dictated by the pressure margins of a model well. We used our proprietary software HeaveSIM™ to calculate the dynamic limits!


Surge & swab calculations for several wells in Norway and Brasil delivered to Equinor in January-August 2019

- We calculated downhole surge & swab induced by rig heave during drill pipe connections in several different wells. Calculations were performed using our proprietary software HeaveSIM™ based on such variables as well trajectory and geometry, drilling fluids data, weather data and rig heave measurements. 

Presentation at the SPE One Day Seminar (Bergen, Norway) in May 2019

- The title of the presentation was "Flow Loop Trial of an Autonomous Downhole Choke for Compensation of Rig Heave-Induced Surge & Swab" and the paper was co-authored by Techni, NTNU and Equinor. SPE-196641.

Presentation at the SPE Workshop on Innovative Arctic Technologies (Harstad, Norway) in March 2019

- The title of the presentation was "Influence of Well Geometry, Weather Conditions and Rig Type on Surge & Swab During Drill Pipe Connections in the Barents Sea" and the paper was co-authored by OMV, Vår Energi, NTNU and Equinor.


Presentation at the SPE/IADC Drilling Conference and Exhibition (The Hague, The Netherlands) in March 2019

- The title of the presentation was "Verification of Downhole Choke Technology in a Simulator Using Data from a North Sea Well" and the paper was co-authored by NTNU and Equinor. SPE-194143, also published in the SPE Drilling & Completion Journal. https://bit.ly/2lmO4wV

White paper on the HeaveLock™ autonomous downhole tool published in SPE The First in August 2018

- This paper described the downhole choking concept and its utilization as an enabler for implementation of MPD on floating rigs in harsh weather environment. https://bit.ly/2lmqtwj

Presentation at the SPE/IADC Drilling Conference and Exhibition (Houston, USA) in April 2018

- The title of the presentation was "Attenuating Heave-Induced Pressure Oscillations using Automated Down-hole Choking" and the paper was co-authored by NTNU, Techni and Equinor. SPE-189657. https://bit.ly/2mlK1Bg





Visitor Address: 

Havnegata 7

7010 Trondheim


Postal Address: 

Heavelock Solutions AS

Postboks 1284 Torgard

7462 Trondheim



Tel: +47 481 40 339





  • Hvit Linkedin Ikon

Chairman of the board

20 years of experience developing, financing and leading technology companies.  



  • Hvit Linkedin Ikon

Board director and inventor

Professor of cybernetics at NTNU. Expert in drilling control and simulation.



  • Hvit Linkedin Ikon

Board director and inventor 

Professor of petroleum technology at NTNU. Expert in drilling and petroleum technology. 



  • Hvit Linkedin Ikon

Board director

CEO of Techni, one of the largest design & engineering houses in Norway.



  • Hvit Linkedin Ikon

Senior Adviser, Drilling and MPD

Rob has spent more than 30 years working with drilling in service and operator companies across the globe. He specializes in advanced drilling solutions such as UBD, MPD and Coiled Tubing drilling. Robert works with Heavelock AS as part-time advisor.



  • Hvit Linkedin Ikon

Senior Adviser, Technology

Thomas graduated with a PhD in Chemical Engineering from NTNU and spent the first 10 yers of his career with Statoil in various positions within R&D and projects. His latest position was CTO in Resman where he was responsible for all technology and development matters.



  • Hvit Linkedin Ikon

Adviser, Downhole Tools

MSc in Mechanical Engineering from NTNU. Background from Schlumberger, where Torgeir had spent 7 years working as Mechanical Engineer developing downhole tools for drilling. Field experience from land-based operations in the US. Torgeir works with Heavelock AS as part-time advisor.



  • Hvit Linkedin Ikon

Chief Executive Officer (CEO) 

MSc in Cybernetics from the NTNU and business studies at BI. More than 10 years of experience within oil & gas projects. Prior to joining Heavelock AS Martin had worked 8 years for Norwegian oilfield service company Reinertsen with maintenance and modifications on the Norwegian Continental Shelf.



  • Hvit Linkedin Ikon

Chief Technology Officer (CTO)

PhD in Process Technology and MBA in Technology Management. Background from various technical, project and operational roles with Norske Skog, Reinertsen, BRI Cleanup and Equinor in Norway and abroad. Considerable offshore experience from NCS, South-China Sea and offshore Brasil. 




  • Hvit Linkedin Ikon

Data Scientist

MSc in Simulation and Visualization from NTNU. Mateus comes from Brazil, where he had worked on student assignments for Petrobras during his studies. Excellent academic record.

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