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Derrick Repair and Upgrades


In our 30+ years of experience we have upgraded, modified, repaired, re-certified and inspected almost every type of structure that is out working, regardless of manufacturer or design. Our in-house engineering teams have accumulated many years of experience in work-scopes concerning upgrades, allowing us to provide rapid and proven derrick solutions that meet your requirements. Our API 4F and 8C accreditation provide you with the assurance that we are qualified to undertake such work-scopes.

Installation of field upgrades is a particular strength of our business. We have a large pool of offshore/site crews and personnel that undertake onsite upgrades and modifications at locations all over the world.

Typical projects include:

  • TD Upgrades
  • Bolt Changes
  • Derrick Lighting
  • Derrick Extensions
  • Casing Stabbing Boards
  • Replacement Guide Rails
  • Increased Setback Capacity
  • Replacement Racking Boards
  • Increased Hook Load Capacity
  • High and Low Pressure Piping
  • Derrick Windwall and Heat Shield Cladding
  • Derrick Modifications for Introduction of Pipe Handling


As part of our core business activities, DSL provides Operators and Drilling Contractors with a wide range of construction services to cover most work-scopes associated with rig/drilling package upgrades, refurbishment and repair. The Apache Forties Field in the North Sea is a great example of the broad range of support that we can provide to our customers (either turnkey or individual work-scopes). For this project, we undertook the turnkey upgrade and refurbishment of the drilling packages and systems on the four platforms that are installed on this development. Support included – project management, engineering and detailed design, fabrication, offshore installation and commissioning.

The work scopes on this project included the design, manufacturing and installation of the following on the four platforms:

  • Structural analysis and verification of derrick capacity and refurbishment of same
  • Design, procurement and installation of replacement drag chains for rig skidding
  • Procurement and installation of Cuttings Re-injection System and associated piping
  • Electrical design and load calculations for Platform Power Supplies
  • Installation of Power Supplies, Cable Support and Switchboard Upgrades
  • Upgrades for installation of Varco & MH TD Systems and Roughnecks
  • Design, procurement and installation of Variable Frequency Drive System
  • Design, fabrication and installation of Diverter Lines
  • Design, fabrication and installation of Samson Barrier
  • Supply and installation of third Mud Pumps
  • Conversion of Mud Return System to OBM
  • Conversion of Brine Loading System
  • Conversion of Mud Transfer System
  • OBM HVAC upgrade-Integration


Land rig refurbishment, upgrades and re-certification form a significant part of DSL’s core business worldwide. From carrier rigs to the biggest drilling rigs, we provide a range of services from complete overhaul to upgrade for new equipment/capacity and refurbishment of individual components. We have a long history of working with masts and substructures, along with carrier and trailer rigs of almost every manufacturer there is or has been. Our extensive knowledge and background is at your disposal to support whatever you need done to your rig. Our worldwide locations ensure that we are able to support you wherever you may be. API audits DSL annually for its various licenses and for rig refurbishments; these certifications include include API Q1 and ISO 9001:2008. As an API 4F and 8C licensed company, we have the qualifications and accreditation to re-certify your drilling structure.

Some of the common upgrades that we undertake include:


  • Top Drive upgrades
  • Rig Moving Systems
  • Replacement of components
  • Upgrade of BOP handling systems
  • Refurbishment of drilling structure
  • Modifications to increase rig capacity
  • Replacement masts and substructures
  • Conversion to helicopter transportable rigs
  • Re-Certification of structure in accordance with API 4F


DSL has comprehensive, in-house, engineering resources covering a wide range of disciplines and work-scopes – including electrical, mechanical and structural engineering, which are supported by the latest design software. We have permanent engineering teams in Great Yarmouth, Aberdeen and Dubai that undertake work-scopes covering the broad spectrum of systems on-board an installation from power generation, mud systems, drilling structures and rig moving;  just to name a few. For projects such as general fabrication, we can either design based on your requirements in-house, or provide additional support to your own engineering teams on an ad hoc basis for engineering and/or drafting.


CMC removals are normally complex work scopes requiring forward planning and preparation to ensure that the work is completed as efficiently and safely as possible. Through our significant track record of Derrick CMC removals worldwide, DSL has both established and enhanced our operational procedures, risk assessments and lift plans of various makes and models – making us the most experienced and competent company for undertaking this type of work.


DSL employs Rig Building Crews all over the world to erect, outfit, decommission, extend and modify derricks. DSL is the only company in the industry that provides API Certified Derrick Technicians, who are trained and qualified at our API and IADC approved training academy. This training involves all aspects of derrick and drilling structure work including derrick erection, crown block removal and installation, changing out racking boards, guide rails, derrick bolts and many other work-scopes.


We also supply the following products for all makes and models of derricks, masts and substructures:

  • Derrick bolts
  • Drilling derricks
  • Guide rails and braces
  • Masts and substructures
  • Racking Board assemblies
  • Replacement derrick members
  • Derrick and land rig accessories
  • Replacement masts for carrier rigs
  • Work-over masts and substructures
  • Masts and substructures for desert rigs
  • Derrick and drill floor windwall cladding