GB2638649A

GB2638649A - Inspection method and associated apparatus

Info

Publication number: GB2638649A
Application number: GB2317391.7A
Authority: GB
Inventors: Constantinis Daniel
Original assignee: Em&i Maritime Ltd
Current assignee: Em&i Maritime Ltd
Priority date: 2023-11-13
Filing date: 2023-11-13
Publication date: 2025-09-03
Also published as: WO2025103696A1; GB202317391D0

Abstract

A method fo inspecting at least a portion of an object comprising, loading the object 4, measuring at least one surface of the portion of the object while it is loaded 6, the measurement providing a measurement of a deformation and/or deflection of the portion of the loaded object. A simulated model of the object is provided and the loading of the object simulated by adapting the simulated model to include a corresponding simulated loading, adapting at least one property of the simulated model dependent on the measurement of the object under load 8. The simulated model preferably involving finite element analysis or a finite element model and preferably derives an expected deformation and/or deflection of the simulated model of the portion of the object in dependence of the simulated loading and comparing the expected deformation with the measured deformation of the loaded object. The adaptation of the model preferably comprising altering at least one property of the simulated object until the expected deformation matches the measured deformation. The finite element model preferably being used to calculate residual strength of a particular point on the object based on the expected deflection and/or deformation. The method preferably involving measuring the surface of the object my scanning using optical or laser scanning.

Description

INSPECTION METHOD AND ASSOCIATED APPARATUS

The present invention relates to a method of inspecting an object, particularly, but not exclusively, a portion of a marine object, such as an offshore object; and associated apparatus.

BACKGROUND

The Oil/Gas and indeed many other industries are concerned with safety risks. There are numerous objects on Oil / Gas assets that are often safety critical and need to comply with regulatory and corporate standards. When designing objects, particularly marine objects for use offshore in safety-critical industries, to minimise risks and ensure that safety standards are met, object properties are calculated. For example, models and simulations can be used to calculate object dimensions and materials. Finite Element Analysis ("FEA") can be used to help select or optimize geometries and materials when designing the objects for production. Dependent upon intended use, factors of safety can be used in the calculations to ensure the object can withstand extreme envisaged usage scenarios.

During and after production, quality controls can be performed to check whether the physical manufactured product meets the design specifications. For example, depending on particular manufacturing processes, the product may deviate from a target property or dimension. Accordingly, the design specifications typically include windows or ranges, defined as tolerances for relevant dimensions or parameters.

Sometimes, during a product's lifetime, inspections require to be performed. At least some situations require personnel entry into confined spaces. For example, industries, such as Oil/Gas, stipulate a regulatory and classification requirement to inspect these confined spaces at regular intervals to assure the integrity of the structure. Such inspections involve having a competent person carry out a General Visual Inspection (GVI) and a Close Visual Inspection (CVO of critical parts of the structure and an assessment of any structural deformation by various visual and/or mechanical means.

These inspections are normally carried out by making the tank safe for man entry, cleaning the surfaces to be inspected to a given standard and providing safe access and egress to the components that require inspection. This requires considerable time, cost and renders the tank unavailable for use.

Where the structure shows signs of corrosion then there may be a further requirement to measure the remaining thickness of the steel to confirm the structural and leak integrity of the component or tank respectively.

Regulators and classification societies have prescribed that any inspection methods must provide a particular quality and scope of inspection to provide a GVI, CVI, structural deformation survey and wall thickness measurement of critical components where there is evidence of corrosion.

Entry into such confined spaces can require trained personnel, qualified in appropriate safety procedures. Additional risks are encountered when the confined space involves working at height, for example in a large storage tank or on a ship or offshore production facility. Again this can require personnel to be suitably trained to meet safety requirements for such work.

Furthermore, inspections may be required in hazardous areas. Hazardous areas are typically areas where flammable liquids, vapours, gases or combustible dusts are likely to occur in quantities sufficient to cause a hazard risk, such as of fire or explosion. Hazardous environments or areas are sometimes referred to as "Ex Locations", "Zoned Areas", "Explosive Atmospheres" or "ATEX Areas". Consequently, equipment that is certified for use in these areas is often called "ATEX Equipment", "HAE" or "Ex Equipment".

Inspection of pressure systems and other components on large industrial assets both on and offshore can be costly but needed to meet regulatory requirements and to carry out maintenance.

Previously, the present inventor has attempted to improve inspection, such as disclosed in international PCT patent application W02017/191447, the contents of which are incorporated herein.

It may be an object of one or more aspects, examples, embodiments, or claims of the present disclosure to at least mitigate or ameliorate one or more problems associated with the prior art.

SUMMARY

According to an aspect of the invention, there is provided a method of inspecting at least a portion of an object. The object may comprise a marine object. The object may comprise an offshore object. The object may comprise a structure. The object may comprise an at least partially-floating structure. The object may comprise a vessel, such as a floating marine vessel. The object may be on or part of a moving ship or Floating Production, Storage and Offloading unit (FPSO) or Mobile Offshore Drilling Unit or Accommodation Vessel for example. The method may comprise a short-range inspection. The vessel may comprise a container, such as for containing a material, fluid, or the like. The method may comprise inspecting at least a portion of a physical marine structure.

The method may comprise measuring the portion of the object. The method may comprise measuring the portion of the physical object. The method may comprise loading the portion of the object. The method may comprise measuring at least one surface of the portion of the object. The method may comprise measuring at least one surface of the portion of the object, whilst the portion of the object is loaded. The measuring may provide a measurement of a deformation and/or deflection of the portion of the object.

The method may comprise providing a simulated model of the physical object. The simulated model may comprise a Finite Element Model ("FEM"). The simulated model may comprise a simulation of the physical object. The method may comprise simulating the loading of the of the portion of the object. The method may comprise simulating the loading of the of the portion of the object. The method may comprise simulating the loading of the of the portion of the object by adapting the simulated model to include a corresponding simulated loading. The method may comprise adapting at least one property of the simulated model in dependence of the measurement of the physical object under loading. For example, the method may comprise adapting a property of the simulated object in dependence on the measurement. The property of the simulated object may comprise one or more of: a dimension; a material property; a strength; a stiffness.

Accordingly, in at least some examples, there is provided a method of inspecting at least a portion of a physical marine structure, the method comprising: loading the portion of the physical marine structure; measuring at least one surface of the portion of the physical marine structure, whilst the portion of the physical marine structure is loaded, the measuring providing a measurement of a deformation and/or deflection of the portion of the loaded physical marine structure; providing a simulated model of the physical marine structure; simulating the loading of the physical marine structure by adapting the simulated model to include a corresponding simulated loading; adapting at least one property of the simulated model in dependence of the measurement of the physical marine structure under loading.

The method may comprise measuring the at least one surface with a scanner. Measuring the at least one surface may comprise scanning. The scanning may comprise optical scanning. The scanning may comprise laser scanning. The measuring may comprise measuring a deformation of at least a portion of the object. The measuring may comprise measuring a deflection of the portion of the object. The method may comprise scanning the at least one surface whilst the at least one surface is loaded. The method may comprise scanning the at least one surface whilst the at least one surface is loaded to measure a deformation and/or a deflection of the at least one surface. The scan may acquire a plurality of points, such as a point cloud, associated with one or more surfaces of the portion of the object. The method may comprise scanning, such as disclosed in International PCT patent application PCT/GB2019/051039, published as WO 2019197826 A1, the contents of which are incorporated herein by reference. The scanning may be performed remotely, such as using a camera and/or scanner/s without requiring entry of personnel.

The method may comprise creating the simulated model.

The method may comprise creating the simulated model after the production of the object. For example, the simulated model may be created in dependence upon a measurement/s, such as a scanning/s, of the manufactured object.

In other examples, the simulated model may be created in advance of the production of the object. The method may comprise providing the simulated model prior to production of the object. In at least some examples, the method may comprise designing the object at least partly in dependence of the simulated model.

The method may comprise adapting the simulated model in dependence of a pre-loading measurement's. The method may comprise adapting the simulated model in dependence of an unloaded measurement's. The pre-loading measurement's may comprise a post-production measurement's. The method may comprise measuring the object in an unloaded configuration in advance of a use of the object. For example, the measurement of the unloaded object may be performed after production, such as part of a check or quality control, prior to deployment and use of the object. The method may comprise measuring the object in an unloaded configuration in advance of loading of the object.

The method may comprise measuring a baseline deformation of the physical object. The baseline deformation may comprise an as-built deformation of the physical object. The method may comprise measuring the baseline deformation of the physical object after manufacture of the physical object. The measurement of the baseline deformation may be performed in advance of use of the physical object. The measurement of the baseline deformation may be performed in advance of loading of the physical object.

The load may be a predefined load. The load may comprise a known load. The load may be associated with a weight. The load may be associated with a mass. The load may be associated with a known mass and/or weight. The load may be associated with a pressure. The pressure may comprise a known pressure.

The load may comprise an applied load. The load may be applied for the purpose of performing the loaded measurement, such as of deformation and/or deflection under loading.

The load may comprise a static load. In other examples, the load may comprise a dynamic load. In such examples, the method may comprise measuring the deformation or deflection over a period of time. The period of time may be sufficiently long and of sufficient resolution to capture one or more complete cycles of the dynamic loading.

In at least some examples, the method may comprise a static loading on or in a moving object. For example, the object may be on, or part of, a floating or otherwise moving marine vessel. The scanning may be performed whilst the floating or otherwise moving object is subjected to a static loading.

The load may be associated with a fluid. For example, the portion of the object to be measured may comprise at least a portion of a container. The container may comprise a portion of a marine structure, such as a tank, pressure vessel, or the like. The container may comprise a fluid therein, such as a stored liquid and/or gas. The fluid may comprise a static fluid. For example, the fluid may comprise a non-flowing or non-pumped fluid. The fluid may comprise a fluid at ambient pressure. In other examples, the fluid may comprise a pressurised fluid, such as contained in a pressurised container. A property/ies of the fluid may be known, such that a load associated with the fluid may be known. For example, one or more properties of the fluid may be known selected from one or more of: a mass; a weight; a density; a depth; a volume.

In at least some examples, the method may comprise measuring the load. The measuring of the load may comprise a confirmatory measuring, to confirm the load or at least a value or parameter associated therewith. In other examples, the measuring of the load may comprise a determinative measuring, to establish the load or at least a value or parameter associated therewith. For example, the measuring of the load may comprise a mass or volume of fluid associated with the loading.

The method may comprise measuring from a single side of the portion of the object being measured. The method may comprise measuring the surface of the single side of the portion of the object. The method may comprise measuring a thickness of the portion of the object from the single side. The method may comprise indirectly measuring the thickness of the portion of the object from the single side. The method may comprise deriving the thickness of the portion of the object based upon the single-sided measurement.

The single side may be a same side as to which the loading is applied. Alternatively, the single side may be an opposite side as to which the loading is applied.

The object may deflect or deform towards the single side being measured.

Alternatively, the object may deflect or deform away from the single side being measured.

The single side may be, or may be on, an inside of the portion of the object being measured. For example, the portion of the object may comprise a portion of a container, tank, hull, wall, floor, bulkhead, or the like. The single side may comprise an internal surface/s of the container, tank, hull, wall, floor, bulkhead, or the like. The load may be applied from an opposite side of the object to that being measured. For example, an opposite side of the object, such as another container, tank or chamber on the other side may be filled, or partially filled, with a fluid. The fluid may exert a pressure on the object, such as a container, tank or chamber wall, deforming the tank towards the side being measured. The side being measured may be dry, such as on or in an empty or drained container, tank or chamber. Accordingly, the measurement may be performed in an empty or drained container, tank or chamber. The measurement may be performed without requiring measurement and/or access to both sides of the object being measured (e.g. without requiring measurement and/or access to both an internal side and an external side of the object being measured). In other examples, the measurement may be performed in the fluid-filled, or partially filled, container, tank or chamber.

The method may comprise updating the simulated model in dependence of the measurement/s. The method may comprise simulating the loading of the object by adapting the simulated model to include a corresponding simulated loading. The method may comprise calculating or deriving an expected or calculated deformation or deflection of the simulated model of the portion of the object. The method may comprise calculating or deriving an expected or calculated deformation or deflection of the simulated model of the portion of the object in dependence of the simulated loading. The method may comprise comparing the expected or calculated deformation or deflection of the simulated model of the portion of the object with the measure deformation or deflection of the physical object. The method may comprise adapting at least one property of the simulated model in dependence of the comparison between the deflection or deformation of the object under simulated loading with the measured deflection or deformation of the physical object under physical loading. The method may comprise adapting a property of the simulated object in dependence of the comparison. For example, the method may comprise adapting a dimension or geometry of the simulated object in dependence of a difference between the calculated deflection or deformation under loading and the measured deflection or deformation under loading. The method may comprise adapting the simulated object's property/ies under loading until the calculated deflection or deformation matches the measured deflection or deformation under loading. For example, the method may comprise adapting a thickness of the simulated object portion, such as a simulated object wall, until the adapted thickness provides a calculated deflection or deformation under loading that corresponds to the measured deflection or deformation under loading.

Where the measured deflection or deformation is greater than that calculated using Finite Element Analysis ("FEA") of the FEM of the object under loading, then the FEM of the object may be adapted to decrease the thickness of the FEM of the object. The FEM of the object may be adapted to decrease the thickness of the FEM of the object until the deflection or deformation of the object using the FEA of the FEM under loading corresponds to the measured deflection or deformation of the physical object under loading (the same loading). Accordingly, the likely or actual thickness of the physical object may be derived.

In at least some examples, the method comprises comparing the FEM calculated deflection to the measured deflection. The object may comprise a metal plate wall, such as of a marine vessel bulkhead. If the measured deflection is more than the calculated deflection, (i.e., the plate in real life is thinner than design) the FEA model may be recalculated using reduced thicknesses until the measured and calculated deflections coincide, thus confirming the actual thickness at any chosen points. The deviation between the thickness calculated using FEA in dependence on the measured deflection (or deformation) and the previously-modelled thickness may be associated with a reduction in the thickness. For example, where the modelled thickness is based upon the pre or post-production object prior to use, then the then the deviation in thickness may be associated with a deviation in thickness over time, such as associated with use. For example, the reduction in thickness may be due to general and/or localised corrosion.

The method may comprise planning and/or performing an inspection or an additional inspection in dependence of the results of the comparison of the FEM with the measurements, under loading. For example, if there is a difference between the initially-calculated simulated deflection or deformation and the actual measured deflection or deformation, then an inspection, such as a visual inspection, may be performed. The method may comprise identifying one or more portions of the object with a sufficient deviation in simulated thickness under loading. The method may comprise performing a further inspection of the portion/s of the object. For example, the method may comprise performing an inspection with one or more cameras, scanners and/or thickness gauge/s of the portion/s of the object. In at least some examples, if corrosion appears to be present (e.g. as viewed by a remote camera), the type and extent of corrosion may be visually confirmed.

The method may comprise multiple measurements under loading. For example, the method may comprise multiple measurements under a same known loading, the multiple measurements spread over a period of time. The spread may be an even spread over the period of time, such as at regular frequencies. Additionally, or alternatively, the frequency of the measurements may be determined or adapted in view of the result/s of a measurement/s. For example, where a thickness derived from the FEM, based upon the measured deformation or deflection under loading, is a reduced thickness (being less than a predicted or projected thickness), then the period to a next measurement may be reduced (e.g. frequency of measurement may be increased).

The method may comprise deducing thickness at any portion of the object; such as any point on a surface of the object. Additionally, or alternatively, the method may comprise calculating residual strength at any portion of the object, such as any point on a surface of the object.

Accordingly, in at least some examples, there is provided a method of using a laser scanner to measure deflections at many points in a structure against a given load.

In other words, if we know the load we should be able to see an expected deflection.

We can then go further and say if we see a particular deflection we can use an Finite Element Model (FEM) informed by the deflection at a particular point or area, to calculate residual strength The object may comprise a system or portion thereof. The system may comprise a pressure system. The pressure system may comprise one or more pressure vessel/s.

The object may comprise a pressure vessel. The portion of the object may comprise one or more bulkhead/s.

Accordingly, in at least some examples, there is provided a method of thickness determination of a bulkhead, the method comprising the following steps: 1. performing a baseline survey of a bulkhead to establish as-built deformations; 2. taking a laser scan of the bulkhead under a known load, to measure deformation/deflection across the bulkhead surface; 3. creating a finite element model ("FEM") of the bulkhead, derived from one or more of: the original drawings; material thickness; and material type; 4. incorporating the as-built deformations into the FEM model by morphing the FEM to the survey of as-built deformations; 5. 'loading' the FEM to the same load as was used in the laser scan (item 1 above); 6. comparing the FEM calculated deflection to the measured deflection (item 2 above).

7. If the measured deflection is more than the calculated deflection, (i.e., the plate in real life is thinner than design) the FEA model is recalculated using reduced thicknesses until the measured and calculated deflections coincide, thus confirming the actual thickness at any chosen points.

8. The reduction in thickness may be due to general or localised corrosion.

9. If this corrosion is present on the face of the bulkhead that can be seen (by the remote camera), the type and extent of corrosion can be confirmed visually as well.

The method of inspecting the inside of the vessel may produce an overall or complete image of the inside of the vessel. The overall or complete image of the inside of the vessel is may be used to provide an inspection of the inside of the vessel.

The vessel may be referred to as a confined space. The vessel may be tens of meters in one or more of length, depth and height. The vessel may be a tank on and/or part of a ship. The ship may be a drillship or a cargo ship. The tank may be a ballast and/or water ballast tank. The tank may be a fuel and/or oil tank. The tank may be a J-tank. The vessel may be on or part of a Floating Production, Storage and Offloading unit (FPSO). The vessel may be a pressure vessel.

The one or more objects inside the vessel may be one or more parts of the vessel or one or more components inside the vessel. The one or more surfaces of the inside of the vessel are typically one or more of the inside walls of the vessel.

It may be an advantage of the present invention that the method of inspecting the inside of the vessel has one or more of enhanced safety, reduced cost in preparation and/or inspection and is a faster method of inspecting a vessel which may increase system availability, require fewer personnel and reduce downtime compared to conventional inspection methods.

The method may further include a structural assessment of the object, or portion/s thereof, by a competent person and/or engineer before the steps of using a camera and/or a scanner. The structural assessment will normally identify one or more of the probable deterioration, structural deformation, thickness gauging requirements, anomalies, work scope, defect tolerance standards and reporting standards for and/or in the vessel. The method may include the step of using an ultrasonic scanner and/or non-immersion ultrasonic scanner to measure the thickness of a wall or walls of the vessel. The thickness measurement may comprise a confirmatory measurement to confirm the thickness derived from the FEM by simulation.

The structural assessment by a competent person and/or engineer may also include assessing where a camera and/or scanner will be located for inspecting.

The method may comprise inspecting an inside of a vessel, such as a pressure or storage tank. The method may minimise the need to one or more of clean, vent or empty the vessel during the inspection of the inside of the vessel. This may reduce the overall cost of the method of inspecting the inside of the vessel.

The method may further include filling or at least partially filling the vessel with a liquid, typically water. This may be particularly useful when the vessel has an internal shape such that a camera or scanner cannot gain access to and or see all of the inside of the vessel, one or more objects inside of the vessel or one or more surfaces of the inside of the vessel respectively. The method then may include mounting and/or attaching the camera and/or scanner to a Remotely Operated Vehicle (ROV).

An immersion ultrasonic device and/or other inspection tools may be mounted and/or attached to the Remotely Operated Vehicle (ROV). The immersion ultrasonic device and/or other inspection tools may be used to measure the thickness of a wall or walls of the vessel. The other inspection tools may provide a gauging capability. The Remotely Operated Vehicle (ROV) may be stabilised.

The method may include the step of using the camera to obtain a plurality of visual images of the inside of the vessel. The plurality of visual images may be obtained from a number of different positons to create a photogrammetric image. The photogrammetric image may be used to measure and/or inspect the inside of the vessel, one or more objects inside of the vessel and one or more surfaces of the inside of the vessel.

The method may further include a structural assessment of the vessel by a competent person and/or engineer before the steps of using the camera, first three-dimensional scanner, and second three-dimensional scanner. The structural assessment will normally identify one or more of the probable deterioration, structural deformation, thickness gauging requirements, anomalies, work scope, defect tolerance standards and reporting standards for and/or in the vessel. The method may include the step of using an ultrasonic scanner and/or non-immersion ultrasonic scanner to measure the thickness of a wall or walls of the vessel. The thickness measurement may comprise a confirmatory measurement, such as to confirm the thickness derived from the FEM.

The method may comprise compiling data, such as historical data. The method may comprise scanning, such as disclosed in International PCT patent application PCT/GB2019/051045, published as WO 2019197830 A1, the contents of which are incorporated herein by reference.

The method may comprise inspecting multiple objects. The method may comprise inspecting multiple objects during a single inspection. The single inspection may comprise multiple inspection scans and/or measurements, such as scans under loading/s (e.g. different known loadings).

The method may comprise storing the inspection results and/or analysis/es or data derived therefrom, such as storing in a database. The method may comprise compiling the inspection results and/or analysis/es or data derived therefrom. The method may comprise compiling the inspection results and/or analysis/es or data over a period of time for a single object. Additionally, or alternatively, method may comprise compiling the inspection results and/or analysis/es or data for multiple objects.

The method may comprise analysing the compiled inspection results and/or analysis/es or data. The analysis may comprise a statistical analysis. The analysis may comprise a risk or risk factor analysis, such as a Failure Modes and Effects Analysis (FMEA) or the like. The method may comprise performing a targeted inspection. The method may comprise performing a targeted inspection in dependence on the compiled inspection results and/or analysis/es or data. The method may comprise performing a targeted inspection in dependence on a most likely and/or most critical failure location/s and/or object/s and/or feature/s.

The method may comprise compiling an inventory of objects, and/or inspection results and/or analysis/es or data associated therewith, such as in a database. The method may comprise grading the objects, such as by criticality -typically in dependence on the inspection results and/or analysis/es or data.

The method may comprise determining and/or following an inspection programme. The method may comprise identifying which object/s require or are likely to require inspection. The method may comprise identifying or determining a detailed procedure for the inspection of each object. The detailed procedure may be determined in dependence on a probable defect or failure type/s; and may comprise an associated, preferably validated, method for detecting such defects or failures. The detailed procedure may be determined in dependence on the analysis, such as an FMEA.

The steps of the method may be in any order. The method of inspecting the object may be referred to as a method of inspection.

It may be an advantage of the present invention that the method of inspection is equivalent or at least substantially equivalent, such as in quality and/or scope, to the inspection that a competent person would achieve with a conventional inspection, such as a prescribed or certified inspection or detailed inspection. It may be an advantage of the present invention that the method of inspecting the object is in a manner and/or quality and/or resolution at least equivalent to that required by regulation. The manner and/or quality and/or resolution may be at least equivalent to that obtainable by conventional inspection or general inspection, or at least comparable thereto. The manner and/or quality and/or resolution may be at least equivalent to that obtainable by visual inspection, or at least comparable thereto. The manner and/or quality and/or resolution may be at least equivalent to that obtainable by electrical testing. It may be an advantage of the present invention that the method of inspecting the object is in a manner and/or quality and/or resolution at least equivalent to that which a skilled surveyor or engineer would achieve if they had access to the object, such as with dismantling or disassembly, and optionally isolation, of the object.

It may be an advantage of the present invention that the method of inspecting the vessel is in a manner and/or quality and/or resolution at least equivalent to that required by regulation. The manner and/or quality and/or resolution may be at least equivalent to that obtainable by ultrasonic thickness measurement, or at least comparable thereto. It may be an advantage of the present invention that the method of inspecting the vessel is in a manner and/or quality and/or resolution at least equivalent to that which a skilled surveyor or engineer would achieve if they had access to all parts of the vessel including within 'arm's length' of components, such as subject to a Close Visual Inspection, in particular if the skilled surveyor or engineer were inside the vessel and had such access.

Inspecting the vessel may comprise inspecting an inside of the vessel. The method may comprise inspecting the vessel without a person entering or being required to enter the vessel. The method may comprise the entry of only apparatus, such as scanning apparatus, into the vessel. In at least some examples, the method comprises measuring a portion of the object, such as an adjacent tank, compartment, container, chamber or wall defining or separating such -without requiring access of personnel and/or equipment therein.

The method may comprise analysing data to predict or to project a property or characteristic of the object. The property or characteristic may comprise a current or existing property or characteristic. Additionally, or alternatively, the property or characteristic may comprise a future property or characteristic. The property or characteristic may comprise a known or a measured property or characteristic.

Additionally, or alternatively, the property or characteristic may comprise an unknown or an unmeasured property or characteristic, such as a target property or characteristic. The predicted or projected property or characteristic may be predicted or projected for a particular parameter or variable, such as a particular time or use parameter. In at least some examples, the predicted or projected property or characteristic may be associated with a life or use of the object. Accordingly, a development of the property or characteristic may be predicted or projected over a period of time.

The method may comprise generating a model or simulation of the object and/or the property or characteristic thereof. The mode or simulation may comprise an effective fingerprint associated with the object. The method may comprise fingerprinting the object. For example, the method may comprise associating each object with a unique data set. The unique data set may be indicative of the property/ies or characteristic/s of the object at a plurality of locations of the object, such as distributed along or through the object. The method may comprise analysing the object to determine the property or characteristic and or location/s of the object corresponding to the property or characteristic. The property or characteristic may comprise a wall thickness, such as a minimum wall thickness.

The method may comprise determining a predicted or projected wall thickness. The method may comprise determining a predicted or projected wall thickness of one or more object/s at one or more location of the object/s. The predicted or projected wall thickness may comprise a minimum thickness.

The method may comprise determining a predicted or projected wall thickness in dependence on one or more parameter/s. The one or more parameter/s may comprise historical data. The historical data may comprise data for the object for which the wall thickness is to be predicted or projected, such as compiled from previous inspection/s, measurement/s and/or determinations. The previous inspection/s, measurement/s and/or determinations may be of the object. Additionally, or alternatively, the historical data may comprise data for other objects, such as with one or more similar traits or features to the object for which the wall thickness is to be predicted or projected. The one or more similar traits or features may comprise one or more of: an object type; a material type; a starting wall thickness; an environment of use; a pressure of use; a system of use; a fluid for use therewith or therein.

The method may comprise determining an amount of data to collect at an inspection, such as a next inspection, of the object.

The method may comprise projecting how the object will age. The method may comprise projecting how much inspection data is required to assure the operator and regulator that the risk is within a pre-agreed level.

In at least some examples, the method comprises at least mitigating against an unexpected loss of containment of the fluids inside high risk piping or pressure vessels. For example, the method may comprise at least mitigating against excessive external or internal corrosion of the pressure retaining walls to the extent where at some point in the pressure system the remaining wall thickness is no longer able to contain the pressure of the contained fluids. The method may comprise a risk based inspection (RBI) to focus inspection methods and inspection intervals on the probable failure mechanisms of high risk objects or components.

The method may comprise determining the amount and/or frequency of inspections (e.g. deflection or deformation measurements under loading) to provide inspection thickness data and a required 'confidence factor' that assures the stakeholders that it is improbable that any part of the object, such as the pressure system, is going to fail under normal operating conditions.

The object may comprise the vessel. The vessel may be on or part of a moving ship or Floating Production, Storage and Offloading unit (FPSO) or Mobile Offshore Drilling Unit or Accommodation Vessel for example. The method may comprise a short-range inspection. The vessel may comprise a container, such as for containing a material, fluid, or the like.

The vessel may be referred to as a confined space. The vessel may be tens of meters in one or more of length, depth and height. The vessel may be a tank on and/or part of a ship. The ship may be a drillship or a cargo ship. The tank may be a ballast and/or water ballast tank. The tank may be a fuel and/or oil tank. The tank may be a J-tank.

The vessel may be on or part of a Floating Production, Storage and Offloading unit (FPSO). The vessel may be a pressure vessel.

The object may be for, in or from a hazardous environment or area. The object may comprise hazardous area apparatus or equipment, or at least a component thereof.

The method may comprise a non-invasive inspection. The method may comprise the inspection of an electrical and/or electronic component/s or system/s. The method may comprise obtaining a inspection result, such as a inspection image, of the object. The method may comprise inspection without isolating the object, such as without electrically isolating the object. The method may comprise inspection without dismantling or disassembling the object, or component/s thereof.

It may be an advantage of the present invention, that method allows an effective management of the object or system, particularly given, for example, the number of items of equipment potentially involved, their accessibility, the varying risks they represent or a lack of prior or existing information on asset registers or current condition.

The method may comprise inspecting the object multiple times. The multiple times may be during separate discrete inspections, such as separated by weeks, months and/or years. The method may comprise compiling data from multiple inspections. The method may comprise compiling data from multiple inspections of a single object. The method may comprise compiling data from multiple inspection of the single object over a lifespan, or period thereof, of the single object.

The method may comprise inspecting multiple objects. The method may comprise inspecting multiple objects during a single inspection. The single inspection may comprise multiple inspection scans and/or measurements, such as under multiple same loadings and/or multiple different loadings (e.g. with different known forces applied).

According to an aspect of this invention, there is provided an apparatus configured to perform a method according to an aspect, claim, embodiment or example of this disclosure.

According to an aspect of the invention, there is provided a controller arranged to perform a method according to an aspect, claim, embodiment or example of this disclosure.

According to an aspect of the invention, there is provided a system comprising a controller according to an aspect, claim, embodiment or example of this disclosure, or a system arranged to perform a method according to an aspect, claim, embodiment or example of this disclosure.

According to an aspect of the invention, there is provided computer software which, 35 when executed by a processing means, is arranged to perform a method according to any aspect, claim, embodiment or example of this disclosure. The computer software may be stored on a computer readable medium. The computer software may be tangibly stored on a computer readable medium. The computer readable medium may be non-transitory.

Any controller or controllers described herein may suitably comprise a control unit or computational device having one or more electronic processors. Thus, the system may comprise a single control unit or electronic controller or alternatively different functions of the controller may be embodied in, or hosted in, different control units or controllers. As used herein the term "controller or "control unit" will be understood to include both a single control unit or controller and a plurality of control units or controllers collectively operating to provide any stated control functionality. To configure a controller, a suitable set of instructions may be provided which, when executed, cause said control unit or computational device to implement the control techniques specified herein. The set of instructions may suitably be embedded in said one or more electronic processors. Alternatively, the set of instructions may be provided as software saved on one or more memory associated with said controller to be executed on said computational device. A first controller may be implemented in software run on one or more processors. One or more other controllers may be implemented in software run on one or more processors, optionally the same one or more processors as the first controller. Other suitable arrangements may also be used.

Within the scope of this disclosure it is expressly intended that the various aspects, embodiments, examples and alternatives set out in the preceding paragraphs, in the claims and/or in the following description and drawings, and in particular the individual features thereof, may be taken independently or in any combination. That is, all embodiments and/or features of any embodiment can be combined in any way and/or combination, unless such features are incompatible. The applicant reserves the right to change any originally filed claim or file any new claim accordingly, including the right to amend any originally filed claim to depend from and/or incorporate any feature of any other claim although not originally claimed in that manner.

BRIEF DESCRIPTION

An embodiment of the invention will now be described by way of example only and with reference to the accompanying drawings, in which: Figure 1 shows a method of inspecting an object; Figure 2 shows an example of a physical object; Figure 3 shows a schematic portion of the object of Figure 2; Figure 4 shows a FEM of the portion of Figure 3; Figure 5 shows a schematic example of a 2D view of the portion of Figure 3, with the portion shown in an unloaded configuration in Figure 5a and in a loaded configuration in Figure 5b; Figure 5 shows a schematic example of a 2D view of the portion of Figure 3, with the portion shown in an unloaded configuration in Figure 5a and in a loaded configuration in Figure 5b; Figure 6 shows a schematic example of a 2D view of the FEM of Figure 4, with the portion shown in an unloaded configuration in Figure 6a and in a loaded configuration in Figure 6b; Figure 7 shows a schematic 2D view of a scanning of the portion of Figure 3 with the portion under a known loading; Figure 8 shows a schematic view of the scanned surface obtained with the scanning of Figure 7; and Figure 9 shows schematically the adaptation of the FEM of Figure 6 in view of the scanned surface of Figure 8, with Figure 9a showing an original or initial FEM of the unloaded portion, Figure 9b showing the original or initial FEM with the portion loaded with the known loading; Figure 9c shows the FEM adapted in view of the measured deflection or deformation obtained with the scanning of Figure 7; and Figure 9d shows the adapted FEM in an unloaded configuration, after adaptation.

DETAILED DESCRIPTION

There is herein described a method 2 of inspecting an object 10. Referring firstly to Figure 1, there is shown an optional preliminary step 4 of the method 2 of applying a load to the object 10. This can be when the object is otherwise unloaded. For example, a known synthetic load, such as with a weight or other applied mechanical force can be applied to the object 10. Accordingly, the object 10 is loaded. With the object 10 loaded, a step 6 of measuring deflection/deformation of the object 10 under loading can be performed. Based upon the results of the loaded measurement in the previous step 6, a subsequent step 8 can be performed of adapting a Finite Element Model ("FEM") of the object 10 (in dependence of the loaded measurement).

Referring now to Figure 2, there is shown an example object 10. Here the object 10 is a portion of a FPSO, showing a transverse bulkhead. It will be appreciated that, conventionally such bulkheads are regularly inspected by personnel accessing the surface of the bulkhead to perform visual inspections (e.g. CVI, GVI) and measurements, such as ultrasonic thickness measurements. However, with the method disclosed with this application, no such personnel access is required. Rather a scan of the bulkhead (or portion/s thereof) is performed remotely, using one or more cameras or scanners. In particular, a laser scan of the bulkhead 12 as shown can be performed to gather a cloud of data points representative of the (visible) surface/s of the bulkhead as shown in Figure 2. It will be appreciated that on another side of a wall of the bulkhead 12 shown in Figure 2, a fluid (e.g. oil) is stored. Accordingly, a pressure is exerted on the wall of the bulkhead. This pressure is known, based upon the volume/depth of the fluid on the other side of the wall. As such, when the wall of the shown bulkhead 12 is scanned, the resultant surface/s are that of a loaded object: the surface of the wall of the bulkhead is deformed, deflected away from the fluid, into the compartment shown where the scanning measurement is performed.

Referring now to Figure 3, there is shown schematically a portion of the wall of the bulkhead 12 of Figure 2. Figure 4 shows a FEM 112 of the portion 12 of Figure 3. Generally, the FEM 112 depicts features corresponding to that of the actual, physical portion 12, with the reference numerals increment by 100. Referring now to Figure 5, there is shown a schematic example of a 2D view of the portion 12 of Figure 3, with the portion 12 shown in an unloaded configuration in Figure 5a and in a loaded configuration in Figure 5b. Here the actual thickness 14 of the portion 12 can be readily viewed, in the 2D cross-sectional examples.

Similarly, Figure 6 shows a schematic example of a 2D view of the FEM 112 of Figure 4, with the portion 112 shown in an unloaded configuration in Figure 6a and in a loaded configuration in Figure 6b. Here, it can be seen that the example shows similar thicknesses 14, 114 of the actual and FEM portions 12, 112. Such a FEM and model is typical of existing use of FEA, whereby FEM is used to merely replicate the actual, physical model 12.

Referring now to Figure 7, there is shown a schematic 2D view of a scanning of the portion 12 of Figure 3 with the portion 12 under a known loading. The scanning of a single surface of the portion 12 is represented by the horizontal arrows. Figure 8 shows a schematic view of the scanned surface 16 obtained with the scanning of Figure 7.

Referring now to Figure 9, there is shown schematically the adaptation of the FEM 112 of Figure 6 in view of the scanned surface 16 of Figure 8. Figure 9a shows an original or initial FEM 112 of the unloaded portion, corresponding to Figure 6a. Figure 9b shows the original or initial FEM 112 with the portion loaded with the known loading.

Figure 9b also shows a representation 116 of the actual measured deformation 16 of Figure 8. Here it can be seen that there is a deviation or discrepancy between the actual measured deformation under loading of Figure 8 and the calculated deformation under the loading according to FEA, as shown in Figure 9b. Accordingly, it can be deduced that there is a deviation or a discrepancy in the FEM. Here, it can be assumed that the deviation or discrepancy is attributable to a deviation or discrepancy between the modelled thickness 114 of the FEM 112 and the actual thickness 14 of the physical portion 12. Accordingly, the FEM 112 can be adjusted to adapt the thickness 114 of the FEM 112 based upon the magnitude of the deviation between the measured and originally calculated deformations. Figure 9c shows the FEM 112 adapted in view of the measured deflection or deformation obtained with the scanning of Figure 7, with the thickness 114 in this example reduced, to reflect the larger measured deformation in Figure 8 than originally calculated with the FEM 112 in Figure 9b. Figure 9d shows the adapted FEM 112 in an unloaded configuration, after adaptation, merely to provide an indication of FEM thickness 114 reflecting that of actual thickness 14 of the physical portion of the bulkhead 12. It will be appreciated, that the thickness 114 of the FEM 112 can be calculated based upon the magnitude of the deviation between measured and originally-calculated deformations. In some examples, the adapted FEM thickness 114 can be iteratively derived, by variation of the FEM thickness 114. Where there is a deviation between measured and FEM calculated thicknesses 14, 114, this can be converted to a rate, such as a rate of change of thickness -or even a rate of corrosion.

The time factor of the rate can be determined based upon the timing of the creation or setting of the original FEM thickness 114, as shown in Figure 9a. For example, where the original FEM thickness 114 shown in Figure 9a is based upon a production or post-production (e.g. QC) FEM 112 on the bulkhead portion 12, then the time between that creation of the production or post-production FEM 112 and the performance of the measurement scanning of Figure 8 can be used as the time factor in calculating the rate. It will also be appreciated that multiple scans such as that shown in Figure 8 can be performed over a period of time, with the intervals of that period and the development of changes in thickness 14 of the bulkhead portion 12 (as determined by the development of changes in thickness 114 of the FEM model 112 based upon the multiple scans) being used to calculate the rate -or rates, if the rate also changes over time.

The thickness 114 can be used to assess numerous operational activities. For example, timing and extent of a next inspection can be planned. Likewise, any additional inspection, if deemed necessary, such as confirmatory thickness measurements; and/or remedial or maintenance work, can also be planned.

It will be appreciated that in at least some examples, the method provides a thickness measurement that does not require entry of personnel into confined spaces (such as that shown in Figure 2). Similarly, the method can provide single-sided thickness measurements -without requiring access to both (opposite) sides of an object, such as a bulkhead wall 12 as shown in Figure 2. Furthermore, the thickness measurement can be performed entirely contactlessly; and also entirely remotely. For examples, the scanning of Figure 8 can be performed remotely.

It is an advantage of the present invention that the method of inspecting the vessel is in a manner and/or quality and/or resolution at least equivalent to that required by regulation. The manner and/or quality and/or resolution is at least equivalent to that obtainable by ultrasonic thickness measurement, or at least comparable thereto. It is an advantage of the present invention that the method of inspecting the vessel is in a manner and/or quality and/or resolution at least equivalent to that which a skilled surveyor or engineer would achieve if they had access to all parts of the vessel including within 'arm's length' of components, such as subject to a Close Visual Inspection, in particular if the skilled surveyor or engineer were inside the vessel and had such access.

Inspecting the vessel comprises inspecting an inside of the vessel. The method comprises inspecting the vessel without a person entering or being required to enter the vessel. The method comprises the entry of only apparatus, such as scanning apparatus, into the vessel.

It will be appreciated that embodiments of the present invention can be realised in the form of hardware, software or a combination of hardware and software. Any such software may be stored in the form of volatile or non-volatile storage such as, for example, a storage device like a ROM, whether erasable or rewritable or not, or in the form of memory such as, for example, RAM, memory chips, device or integrated circuits or on an optically or magnetically readable medium such as, for example, a CD, DVD, magnetic disk or magnetic tape. It will be appreciated that the storage devices and storage media are embodiments of machine-readable storage that are suitable for storing a program or programs that, when executed, implement embodiments of the present invention. Accordingly, embodiments provide a program comprising code for implementing a system or method as disclosed in any aspect, example, claim or embodiment of this disclosure, and a machine-readable storage storing such a program. Still further, embodiments of the present disclosure may be conveyed electronically via any medium such as a communication signal carried over a wired or wireless connection and embodiments suitably encompass the same.

All of the features disclosed in this specification (including any accompanying claims, abstract and drawings), and/or all of the steps of any method or process so disclosed, may be combined in any combination, except combinations where at least some of such features and/or steps are mutually exclusive.

Each feature disclosed in this specification (including any accompanying claims, abstract and drawings), may be replaced by alternative features serving the same, equivalent or similar purpose, unless expressly stated otherwise. Thus, unless expressly stated otherwise, each feature disclosed is one example only of a generic series of equivalent or similar features.

The invention is not restricted to the details of any foregoing embodiments. The invention extends to any novel one, or any novel combination, of the features disclosed in this specification (including any accompanying claims, abstract and drawings), or to any novel one, or any novel combination, of the steps of any method or process so disclosed. The claims should not be construed to cover merely the foregoing embodiments, but also any embodiments which fall within the scope of the claims.

Claims

CLAIMS1. A method of inspecting at least a portion of an object, the method comprising: loading the portion of the object; measuring at least one surface of the portion of the object, whilst the portion of the object is loaded, the measuring providing a measurement of a deformation and/or deflection of the portion of the loaded object; providing a simulated model of the object; simulating the loading of the object by adapting the simulated model to include a corresponding simulated loading; adapting at least one property of the simulated model in dependence of the measurement of the object under loading.
2. The method according to any preceding claim, wherein the simulated model comprises a Finite Element Model. *ct
The method according to claim 1 or claim 2, comprising deriving an expected O deformation and/or deflection of the simulated model of the portion of the object in dependence of the simulated loading.
The method according to claim 3, comprising comparing the expected deformation and/or deflection of the simulated model of the portion of the object with the measured deformation and/or deflection of the portion of the loaded object.
5. The method according to claim 4, comprising adapting at least one property of the simulated model in dependence of the comparison between the deflection and/or deformation of the portion of the object under simulated loading with the measured deflection and/or deformation of the object under physical loading.
6. The method according to claim 5, comprising adapting at least one property of the simulated object under loading until the expected deflection and/or deformation matches the measured deflection and/or deformation under physical loading.
7. The method according to claim 6, wherein the at least one property comprises a thickness of the simulated object.
The method according to any one of claims 3 to 7 when dependent upon claim 2, wherein the expected deformation and/or deflection is calculated using Finite Element Analysis of the Finite Element Model, and if the measured deflection and/or deformation is greater than expected deflection and/or deformation, then the Finite Element Model of the object is adapted to decrease the thickness of the Finite Element Model of the object.
9. The method according to claim 8, comprising adapting the Finite Element Model to decrease the thickness of the Finite Element Model of the object until the expected deflection and/or deformation and the measured deflection and/or deformation coincide.
10. The method according to claim 9, comprising deriving the actual thickness of the object from the Finite Element Model.
11. The method according to any one of claims 3 to 10, when dependent upon claim 2, comprising using the Finite Element Model informed by the expected deflection at a particular point of the object to calculate residual strength.
12. The method according to any one of claims 3 to 11 when dependent upon claim 2, comprising planning and/or performing an inspection or an additional inspection in dependence on the comparison of the Finite Element Model expected deflection and/or deformation with the measured deflection and/or deformation.
13. The method according to claim 10, comprising measuring the thickness of the object by using an ultrasonic scanner and/or non-immersion ultrasonic scanner to confirm the thickness derived from the Finite Element Model.
14. The method according to any preceding claim, comprising measuring at least one surface of the portion of the object in advance of loading the portion of the object.
15. The method according to claim 14, comprising measuring an as-built deformation of at least one surface of the portion of the object in advance of loading the portion of the object.
16. The method of claim 15, comprising incorporating the as-built deformations into the simulated model.
17. The method according to any preceding claim, comprising measuring from a single side of the portion of the object being measured.
18. The method according to any preceding claim, wherein the load is a known load.
19. The method according to any preceding claim, wherein the object is on or part of a floating marine vessel or Floating Production, Storage and Offloading unit (FPSO) or Mobile Offshore Drilling Unit or Accommodation Vessel.
20. The method according to any preceding claim, wherein the object is or is part of a bulkhead.
21. The method according to any preceding claim, comprising measuring the at least one surface of the object by scanning.
22. The method according to claim 21, wherein the scanning comprises optical scanning or laser scanning.
23. The method according to any preceding claim, comprising creating the simulated model.
24. The method according to any preceding claim, comprising carrying out the method of inspection on the object multiple times during separate discrete inspection, such as separated by weeks, months and/or years, and compiling data from multiple inspections.O