COPPE/UFRJ Course on Flexible Pipes and Umbilical Cables Introduction to Unbonded Flexible Pipe Manufacturing 04 of December 2007

Transcription

1 Manufacture -1 COPPE/UFRJ Course on Flexible Pipes and Umbilical Cables Introduction to Unbonded Flexible Pipe Manufacturing 04 of December 2007 Judimar Clevelario Technology Manager Wellstream do Brasil 11/23/2007

2 Manufacture -2 Course Outline Flexible Pipe Layers & Functions for a typical structure. Pipe Design Methodology, Standards and Verification. Flexible Pipe Documentation and Acceptance Tests. Pipe Layer Manufacture (for each layer: materials, process, critical parameters, tolerances) Internal Carcass Internal Pressure Sheath & External Sheath Pressure Armor Tapes: Antiwear/Insulation/Antibirdcage Layers Tensile Armor End Fittings: Materials, Machining, Welding, Coating Packaging and Shipping Load Out

3 Manufacture -3 Flexible Pipe Design Make-up Flexbody - (Internal Carcass) The Flexbody is a corrugated interlocked metallic tube with a specified internal diameter. The Flexbody supports the extruded fluid barrier and prevents collapse from hydrostatic pressure or crushing loads applied during the pipe operation. Normally not used in W.I. pipes.

4 Manufacture -4 Flexible Pipe Design Make-up Flexbarrier - (Internal Pressure Sheath) The Flexbarrier is a polymer layer extruded over the Flexbody, or as inner liner in W.I. pipes, to form a boundary for the conveyed fluid. The Flexbarrier material is selected to be chemically resistant to the conveyed fluid and unaffected by its service life conditions.

5 Manufacture -5 Flexible Pipe Design Make-up Flexlok - (Pressure Armour) The Flexlok is a steel hoop strength layer consisting of circumferentially wound profiled wire. The Z-shaped wire is profiled to allow interlocking of the edges as they are formed around the pipe. Some other forms (T H) can be used as shaped wires also.

6 Manufacture -6 Flexible Pipe Design Make-up Flextensile - (Tensile Armour) The Flextensile layer is a helical steel armour layer that resists internal pressure and axial tension. Normally round or flat wires are used, even there are differences between them.

7 Manufacture -7 Flexible Pipe Design Make-up Flexwear - (Anti-wear Layer) The Flexwear is a thin polymer tape layer applied between any two adjacent metallic layers, that by preventing metal-to-metal contact between the layers, prevents wear. Flextape - Tape layers are applied over the tensile armors as a manufacturing aid and to prevent radial birdcaging.

8 Manufacture -8 Flexible Pipe Design Make-up Flexinsul - (Insulation) Flexinsul is a thermal insulation layer used to limit heat loss through the pipe wall to the surrounding environment (normally cold sea water). Is usually provided by circumferentially wound bands, or an extruded special polymer. Crushing resistance is essential.

9 Manufacture -9 Flexible Pipe Design Make-up Flexshield - (External Sheath) Flexshield is an externally extruded polymer barrier, applied to resist mechanical damage and intrusion of seawater into the annulus. Also can help insulating the pipe and can be applied in one or more layers.

10 Manufacture -10 Typical Structure: Layer 2: FLEXBARRIER TM Function: Seal Internal Fluid Material: Nylon PA-11 Thickness: 7 mm Layer: TM Function: Birdcaging Resistance Material: High Strength Glass Filament Thickness: 1 mm Layer 6: TM Function: Birdcaging Resistance Material: High Strength Glass Filament Thickness: 1 mm Layer 4: FLEXWEAR TM Function: Limit Steel Layer Wear, Constrain Flextensile Wires, Manufacturing Aid Material: Nylon Thickness: 2,00 mm Layer: FLEXSHIELD TM Function: Environmental Protection Material: HPDE PT7000 Thickness: 10,00 mm Petrobras - Marlim Sul Pipe ID : 6 inches Water Depth : 1500m Pressure Rating : Mpa Design Temperature : 80 Deg. C Function : Oil / Gas Insulated Flowline Layer 1: FLEXBODY TM Function: Collapse Resistance Material: Stainless Steel Thickness: 9 mm Layer 3: TM Function: Provides Hoop Strength Material: Carbon Steel Thickness: 6.5 mm Layer 5: 1 TM Function: Provides Hoop and Axial Strength Material: Carbon Steel Thickness: 3,00 mm Layer: 5 2 TM Function: Provides Hoop and Axial Strength Material: Carbon Steel Thickness: 3,00 mm Layer: TM Function: Decrease Heat Loss Material: Syntetic Foam PT7000 Thickness: 40,00 mm (total)

11 Manufacture -11 Design Methodology For unbonded Flexible Pipes, Wellstream s design methodology is in accordance to the standards shown on the next slide and consider main issues as: - Material Selection - End Fitting Design - Stress Analysis - Upheaval Buckling - Dynamic Analysis - Axial Compression Resistance Analysis - Flexible Structure - Thermal Analysis - Hydraulic Analysis - Gas Permeation - On bottom Stability - Wear Fatigue - Cathodic Protection - Finite Element Analysis

12 Manufacture -12 Flexible Pipe Standards API 17J - Specification for Unbonded Flexible Pipe Petrobras N-2409-A - Flexible Pipe Specification Must be in compliance on all Petrobras Projects. ISO/CD Petroleum natural gas industries - Drilling and production equipment - Design and operation of subsea system- Part 2: Flexible pipe systems for subsea and marine applications. Bureau Veritas NI 364 DTO ROO E - Non-bonded Flexible Steel Pipes used as Flowlines DNV Rules for Flexible Pipe Petrobras RM s ET s and other specifications - ALL SUPERSEDED BY API 17J RP17B - Recommended Practice for Unbonded Flexible Pipe (sister document to API 17J)

13 Manufacture -13 Pipe Structure Design Verification Design Criteria Pipe Design Global Stress Dynamic Analysis Local F.E. Analysis Service Life Fatigue Analysis See Figures 19, 20 API RP 17B for more detailed process charts for static flowlines and dynamic risers

14 Manufacture -14 Technical Documentation Requirements for Flexible Pipe Design Premises - (ISO ) Design Load Report - (ISO plus RM req.) Design Report - (ISO plus RM req.) Operations Manual - (PB N2409-A item 8.8) Manufacturing Quality Plan (N 2409-A item 8.5) Data Book As built documentation (N 2409 A item 8.6)

15 Manufacture -15 Acceptance Tests The FAT requirements are specified in the Fabrication Specification and Quality Plan. 9.2 Gauge Test 9.3 Hydro Test 9.4 Electrical Continuity/Resistance 9.5 Gas Venting Test

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18 Manufacture -18 Internal Carcass The carcass is a corrugated flexible tube typically made from stainless steel, or special metals to a specific internal and external diameter. It is made from flat strip pre-formed and wound in a spiral around a mandrel interlocking each section together, this gives a continuous length of carcass.

19 Manufacture -19 Storage of pancakes The material is verified for compliance with specifications in accordance with the Manufacturing Quality Plan The rolls of strip are called pancakes and the weight of each depends on the size of the strip that s being used. The approximate weight is 440kg.

20 Manufacture -20 Pancake loaded onto drum The pancakes issued from storage are lifted on to a pancake stand used for unwinding and loading the pancakes on to the machine. The material is fed through a set of guide rollers contained inside an interlocked guard and onto the storage drums. There are two drums, each with a capacity of 1700kg or four pancakes depending on material size used.

21 Manufacture -21 Butt Welding Strip The pancakes are joined using an automatic welding machine, this enables the drum to be loaded with one continuous length of strip and allows the production of a continuously formed carcass length.

22 Manufacture -22 The Pre-bend Roll The strip passes through a flyer head, an entry guide, a progressive die and then forming rollers to shape the strip.

23 Manufacture -23 Mandrel / Winding Rollers The formed strip is wound around a mandrel using winding rolls. The size of the mandrel dictates the internal diameter of the carcass. This can range from 2 up to 16. The winding rolls rotate around the mandrel as the strip is closed to its final interlocked shape.

24 Manufacture -24 Cross section of interlock The formed carcass is slowly pulled away from the mandrel and forming head using a caterpuller.

25 Manufacture -25 Quality Inspection Critical parameters which are checked for tolerances (every 10 meters). External diameter Wall thickness - beginning and end Ovality

26 Manufacture -26 Carcass take up Reel The carcass is taken upon a reel, ready for the extrusion operation.

27 Manufacture -27 Internal Pressure Sheath / External Sheath Extrusion Process For Flexbarrier (polymer fluid barrier) the carcass is passed through the extruder cross-head, where the resin melt is applied over the carcass. Control of extruder volume and line speed, coupled with use of specially sized dies, determine the thickness of the wall around the carcass. High Density Polyethylene (HDPE), Nylon (PA11), and polyvinylidene fluoride (PVDF) as well as other polymers are applied in this process.

28 Manufacture -28 Extrusion Process The required wall thickness is determined by the basic pipe design, material type and / or layer function. Wall thickness and pipe diameter are constantly monitored and checked for holidays or voids. The process is computer controlled ensuring a uniform stressfree extrusion by carefully monitoring and controlling extrusion parameters, including resin moisture content, temperature, pressure, line speed, and quench tank pressure.

29 Manufacture -29 Materials and Storage Raw materials are delivered to the plant in boxes, bags or containers, in the form of granules. Materials are verified for compliance with specifications. The material is protected against contamination by a plastic or foil lined bag.

30 Manufacture -30 PWO s Transfer Stations and Silo s The material is loaded into a silo. Unique silos for each polymer Driers integrated with silos

31 Manufacture -31 The Extruder loader and Hopper From the silo the material is vacuum transferred to the extruder hopper.

32 Manufacture -32 The Crosshead The polymer material passes through the extruder (auger/barrel) and filters, then into the crosshead. Each type of material run through the extruder has it s own heat profile. This is due to individual polymers being processed differently because of mechanical properties.

33 Manufacture -33 Production Reels & Carousel The product is stored on reels or in a carousel as it is processed through each work centre. The reels are also used to transport the product to the customer. Carousels are used when the length of product exceeds the capacity of the production reels or where the SBR is large. Transportation to the customer takes place by loading the product on to the vessel either on reels or in to the vessels own carousel.

34 Manufacture -34 Caterpullers There are two caterpullers on each extrusion line, one is used to pull the pipe from the pay-off Rim drive and feed it down the line at a constant speed. The other one is used to pull the product through the line at a constant speed dictated by UT the catenary setting. The catenary is a necessary function of the extrusion line.

35 Manufacture -35 Quality Inspections Critical dimensions - OD and wall thickness. Wall thickness measured continuously by UT Visual checks are also carried out, and monitoring the manufacturing tolerances are also part of the Operators inspection process.

36 Manufacture -36 Pressure Armor The Flexlok machine applies a shaped, rolled, carbon steel wire which is preformed and interlocked as it is wound around the pipe, providing a smooth, flexible, continuous layer to support the barrier and increase pipe burst pressure. When design and pressure requirements demand higher burst strengths, Flexpress, a wide flat wire, may be wound over the Flexlok layer. Machines that apply from 1 to 4 wires simultaneously are used.

37 Manufacture -37 Bobbin Rewind Flexlok/Flexpress wire is supplied in coils. These have to be loaded onto the Flexlok machine bobbins. The coils are loaded on to the payoff and the wire is strung through the pinch rolls and casting rollers and secured to the bobbin. The wire is then taken up on the bobbin as the rewind rotates and traverses from side to side.

38 Manufacture -38 Welding Process Flexlok wires are welded to maintain a continuous length. Prior to the welding the ends of the wire are prepared. The welding machine is set to the correct wire size and then the wires are clamped in the machine, then welded. The completed welds are ground back to profile then annealed. Upon completion of this process the welds are tested by non destructive testing.

39 Manufacture -39 Critical dimensions - OD, Pitch, Gap, Quality Inspection Diametral gap from barrier Dimensions are recorded every 10 metres and 100% visual inspection of the wire is conducted. The Flexlok welds and the materials used are tracked. The welds and material are recorded on the material traceability record sheet.

40 Manufacture -40 The tape heads are suitable for the application of either two or four tapes. A fabricated steel frame supports the rotating head. The following tapes are applied - Manufacturing aids Anti-bird caging (Deepwater) Anti-wear (Dynamic Risers) Thermal Insulation Taping Head

41 Manufacture -41 Tensile Armour The Armour machine applies a layer of helical steel armour wires to the pipe. The flat wires increase burst strength and give the pipe axial strength. There are two machines that apply the flat wire contra-helically. The flat wire can be of various sizes and tensile strengths depending on the pipe design. As the wire is applied, it runs through pre-form tooling heads which twist the wire so it lays flat against the pipe s surface.

42 Manufacture -42 Materials The armour wire is supplied from the stores in various coil weights. Wire sizes can vary depending on the size of pipe that is being produced.

43 Manufacture -43 Bobbins The armour wire is wound from coils onto bobbins. The number of bobbins and amount of wire used are determined by the pipe design specifications.

44 Manufacture -44 Operation of Rewind The wire is fed through a set of pinch and forming rollers then attached to the bobbin. The bobbin rotates and traverses as the wire is wrapped on to it.

45 Manufacture -45 Welding Process Once the wires have reached a required temperature they are pushed together and pressure welded. Once the wire has been welded the molten scrap is removed off the wire. The operator then dresses the weld with a grinder so that its profile is the same as the rest of the wire. The weld is then checked by the Quality department and documented.

46 Manufacture -46 Armour Line The armour line consists of two Armoring machines which rotate in opposite directions from one another. Stationed throughout the line are tape machines which apply the tape layers.

47 Manufacture -47 Armour Bobbin Loading Bobbins are loaded on to the machine with a loading system. The loader can load up to 4 bobbins at once. Each armour machine is capable of holding up to 96 bobbins.

48 Manufacture -48 Armour tooling Each wire is fed through two sets of tooling rollers. When the wire is pulled through, a helical twist is put in to the wire. The wire helix length and height are then measured to ensure it is in specification. Pre-formation of the armors is a critical process, to ensure the pipe quality, especially if they are risers.

49 Manufacture -49 Start up Once all the wires are pulled down and secured to the pipe the line is started. The pipe is pulled forward and the machine rotates allowing the wire to be wrapped on to the pipe.

50 Manufacture -50 Armour Running The second layer of armour wires are then applied and wrapped with tape. The pipe is pulled through the line by caterpullers and take-up on a reel or carousel.

51 Manufacture -51 Critical Dimensions - OD Diametral gap, Quality Inspections flatness (prevent fishscaling) Gap between adjacent wires Pitch Lay angle

52 Manufacture -52 End Fittings End fittings are custom designed for each flexible pipe structure Terminations can be any design - API/ANSI flanges, hubs, welded, or other Stronger than pipe in burst and failure tension Most common structural material is AISI 4130 low alloy steel Common coatings include electroless nickel plating, Inconel cladding and various epoxies. Installation is a manual process

53 Manufacture -53 Load-out Once the pipe is completed it is secured to a reel or installed in to a carousel. Overview

54 Manufacture -54 Load-out Overview

55 Manufacture -55 Load-out Overview

56 Manufacture -56 Load-out Overview