Drilling and well servicing structures – API4
Drilling and well servicing structures stay safe and operational when structural integrity is verified on a fixed schedule. Work at height continues efficiently, and unplanned downtime stays low because potential defects are found early. Control Union deploys field‑ready inspectors who conduct surveys on location without delaying rig operations.
Compliance and safety through API 4G inspections
Control Union performs complete category III and IV inspections on derrick and substructures in accordance with API Recommended Practice 4G. This standard sets the benchmark for structural assessment of drilling and well servicing equipment.
Certified, multi-skilled inspectors carry out every survey, so a single mobilisation covers the full scope. Organisations gain a clear compliance status and a prioritised maintenance overview in one visit.
Certainty through independent inspections
Multi-skilled certified inspectors
Certified experts handle multiple disciplines in one mobilisation, reducing the need for additional specialists and saving helicopter seats offshore.
IRATA rope access for hard-to-reach areas
Rope access trained inspectors certified to IRATA or equivalent standards reach inaccessible derrick sections safely, so no structural area goes unchecked.
Bolt tension checks integrated in survey
Optional bolt tension checks or torquing verify that all fastening elements are properly tightened, strengthening overall structural integrity during the same visit.
DROPS survey in a single mobilisation
Combining the derrick survey with a Dropped Objects Prevention Scheme assessment addresses falling-object hazards without scheduling a separate inspection campaign.
Fully independent and objective results
Control Union has no ties to insurers or maintenance contractors, guaranteeing 100% objective findings that hold up under regulatory scrutiny.
The proof to your promise
Compliance and operational continuity
Control Union delivers verified structural compliance, supporting rig operations and labour regulation compliance with timely inspection reporting.
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Labour safety regulations are met seamlessly because inspections, evidence and sign-off happen in a single on-location visit.
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Digital reporting reduces paperwork delays, helping vessels and rigs continue operations with minimal scheduling impact.
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Certified experts receive continuous training and recertification, keeping inspection quality consistent across every location and cycle.
Proof to your promise
Frequently asked questions
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Control Union drives global trade forward. As an international and independent partner, we support traders, producers, brands, and logistics service providers in managing risk and safeguarding quality at every step of the supply chain.
From raw material to final product, from processes and systems to installations, we provide insight, assurance, and trust in every link of the chain. We do this through inspections and audits, certification and verification, laboratory analyses, and pest management.
Our global network of experts are embedded in international supply chains across dozens of sectors, including agriculture, food & feed, energy & biofuels, forestry, construction & infrastructure, textiles, maritime, and on- and offshore.
Together, we build future-proof supply chains and confidence in global trade!