Jumper Components and Functions
Contents
Flexible Jumper Components
A typical flexible jumper consists of two end connectors and a flexible pipe between the two connectors.
(1) a stainless steel internal casing, which is designed to resist external pressure;
(2) a thermoplastic sheath, which creates a fluid seal;
(3) a helically wound steel wire, which is designed to resist internal pressure;
(4) an axial armored wire, which is for tensile load reinforcement;
(5) an external polymer sheath for protection from the environment; and
(6) an optional external stainless steel carcass for additional protection.
End Fittings of Flexible Pipe
The standard end fittings installed on the subsea flexible jumper are produced with high specification carbon steel coated with ultra-highcorrosion- resistant and damage-tolerant Nikaflex cladding. Standard terminations are available with API flanges, Grayloc,, Cameron hubs, or hammer unions.
Corrosion Resistance
The subsea jumpers for HP/HT flowlines should use the corrosion resistance of high-performance materials technology to provide a high-pressure, high-temperature, corrosion-resistant pipe. The pipes are designed and specified to resist the worst operational conditions. Especially all pipe structures are well adapted to resist corrosive agents such as water, H2S, CO2, aromatics, acids, and bases without loss of mechanical design life integrity.
Advantages of Flexible Jumpers
The advantages of flexible jumpers can be summarized as follows:
- Flexible;
- H2S and corrosion resistant;
- High-temperature resistance;
- Suitable for dynamic or static service;
- Excellent fatigue design life;
- Can be pigged;
- High resistance to collapse;
- Highly simplified length specification;
- Low U-value.
The disadvantages of flexible jumpers are expansive and smaller diameter for a higher internal pressure.
Rigid Jumper Components
The jumper connection system is configured with steel pipe and mechanical connections at each end for connection to the subsea facility’s piping. The metal seal is retained and sheltered within the connector during installation and retrieval. The connector design is capable of resisting the design loads due to the combined effects of internal pressure, external bending, torsion, tensile, thermal, and installation loads.
In the design of a rigid jumper system, the following items should be considered:
(1) The jumper system is installable by a vessel;
(2) the jumper components are independently retrievable from the connector receiver (or support structure); and
(3) all parts of the system are analyzed with respect to reliability and expected failure rates. The system is designed to minimize failures.
For the design of components for a rigid jumper system, the following items should be considered:
- Materials for the components should be selected so as to minimize potential galling or damage to sealing surfaces during assembly, installation, and maintenance.
- A redundancy philosophy for all parts of the system should be analyzed with respect to safety, cost, and reliability.
- Jumper components of the same design should be interchangeable.
- Standardized parts should be used throughout the system.
- All system components should be compatible with the intended fluids (e.g., all produced, injected, and completed fluids, as applicable) and designed to operate without failure or maintenance for the design life.
- All system components are designed to operate in seawater at the design depth rating. The rigid jumper connection system may consist of the following items:
- Preformed curved steel piping;
- Two connector assemblies, each with an integral or retrievable actuator;
- A soft landing system either integral to the connectors or provided for in the connector actuator (running tool);
- Two connector receivers;
- Hub end closures;
- Jumper measurement tool;
- Fabrication jigs/test stands and lifting tools such as spreader bar and rigging;
- Shipping/transportation stands;
- Testing equipment;
- Running tool;
- Metal seal replacement tool;
- Insulation;
- Connector actuator (running tool);
- Hub cleaning tool;
- Vortex-induced vibration (VIV) suppression devices (if required).
Connector Assembly
The connector assembly may consist of the following components:
- Connector receiver (hub and support structure);
- Connector;
- Connector actuator;
- Soft landing system;
- Connector override tool.
These subsea components are summarized in the following subsections.
Connector Receiver
The connector receiver is mounted on the subsea equipment (such as manifold, PLET, and tree) and includes the connector mating hub, connector alignment system, piping, and support structure. Metal-to-metal seal surfaces for each connector receiver are inlaid with a corrosion-resistant alloy. The connector receiver should include the following components:
(1) an alignment system for guiding the connector onto the mating hub (The alignment system should provide coarse alignment during the initial landing of the jumper connectors onto the connector receivers and align the connector and mating hub during final lowering within the makeup tolerances of the connector.),
(2) a measurement tool interface,
(3) two highquality inclinometers (90 degrees to one another) to measure the inclination of each hub directly, and
(4) padeyes for attachment of a guideline by an ROV.
The connector receiver should be designed with the following requirements in mind:
- The connector receiver should be designed to be a self-contained assembly that can be independently tested prior to integration into the subsea equipment (tree, manifold, PLET, etc.).
- The connector receiver should be field weldable to the subsea equipment (e.g., piping weld).
- The connector should be able to transfer jumper loads and connector override loads into the subsea structure (tree frame, manifold structure, PLET, etc.).
- The connector should protect critical surfaces on the mating hub during installation and retrieval.
- The connector should be designed to accept hub end caps.
Connector
The connector should be used at the end of the jumper piping to lock and seal the mating hub on the connector receiver. The connector should be equipped with the following components:
(1) a mechanism (e.g., collet fingers, or dogs) designed to resist lateral and longitudinal forces that may be encountered in the process of aligning and final lowering, prior to makeup of the connection (the connector is designed to accommodate the design loads);
(2) metal-to-metal seal surfaces inlaid with corrosion resistant alloy; the seal surfaces shall be relatively insensitive to contaminants or minor surface defects and maintain seal integrity in the presence of the maximum bending moments and/or torsional moments;
(3) a metal seal with an elastomeric backup capable of multiple makeups;
(4) mechanical position indicators to indicate lock/unlock operations that are clearly readable by an ROV; and
(5) a mechanical release override or a hydraulic secondary release system.
The connector should be designed to satisfy the following requirements:
- The connector should not permanently deform the mating hub during connection.
- The connector should protect seals and seal surfaces during deployment and retrieval.
- The connector should retain the metal-to-metal seal during jumper installation and retrieval. The metal seal should be capable of being replaced by an ROV without bringing the jumper to the surface.
- The connector should be welded to the jumper pipe. The mechanical unlatch load should not exceed the allowable stresses in the connector receiver structure and piping.
- The connector should provide for an external pressure test of the metalto- metal seal after makeup using an ROV hot stab. The external pressure test is at least 1.25 times the ambient hydrostatic head. A volumetric compensator is included in the seal test circuit. This circuit is constructed with welded fittings wherever possible.
Connector Actuator
The connector actuator may be integral with the connector or independently retrievable from the connector. The connector actuator should include the following components:
(1) ROV handles, which are positioned to observe critical surfaces while guiding the stabbing operation;
(2) an ROV panel with pressure gauges to monitor tool functions, hot stab receptacles, etc., for operation of the soft landing system, connector makeup, and seal test (all control and seal test tubing is to be welded whenever possible; separate ROV hot stabs should be provided for each function);
(3) indicators that allow the ROV to monitor tool hydraulic functions;
(4) a mechanical release (override); and
(5) an optional hydraulic secondary release. Note, however, that even if the hydraulic release is used, the mechanical release is still required.
The connector actuator should be designed considering the following requirements:
- The connector actuator should be designed to preclude accidental unlocking from impact loads, vibration, thermal loads, and any other loads affecting the locking mechanism. A secondary lock should be provided where self-locking mechanisms are used.
- The independently retrievable actuator should be positively locked onto the connector and protect the connector during running, retrieval, and topside handling operations.
Soft Landing System
A soft landing system for retrieval and installation should be provided to minimize the impact loads. This system is an integral part of the connector or connector actuator. It is designed to absorb impact loads while landing the jumper on the connector receivers and to maintain the separation.png){kind=link}
receiver structure. The soft landing system supports the weight of the jumper to isolate the jumper from vessel motion as the connectors are lowered onto the mating hubs. The system pulls the connector and mating hub faces together prior to locking the connector on to the hub by lowering or raising the connector from the mating hub in a controlled manner. It has mechanical position indicators to indicate a lowering operation that are clearly readable by an ROVand allows each end of the jumper to be lowered or raised independently of the other.
Connector Override Tool
The connector override tool should be capable of releasing the mechanical connections if the main actuating device malfunctions.
Jumper Pipe Spool
The jumper pipe spool should include an assembly of straight pipes and bends between the end connections configured to provide compliance during installation and operation. The jumper pipe spool should satisfy the following requirements:
- The pipe should be designed to satisfy the requirements of ASME B31 and API RP 1111, whichever is more stringent.
- Full welds should be required for straight pipes and bends between end connections. Pipe welds should be in accordance with ASME B31.3/ASME Section IX.
- A minimum of 3D pipe bends should be used; 5D pipe bends for pigging purposes.
- Should have sufficient flexibility to accommodate measurement and fabrication tolerances.
- Should satisfy the bending and torsional limits of the connection system.
- Should accommodate the end movements due to pipeline expansion.
- The jumper pipe spool should be fully assembled. The final welds may be performed at a shore base or offshore after jumper measurements have been determined.
- Vortex suppression devices should be incorporated as required.
- Eccentric gravity loads should be minimized.
- Thermal insulation should be incorporated if required.
Hub End Closure
A hub end closure is provided for each hub unless the hub is designed to be equipped with other components (for example, pig catcher, pigging loop) during installation. The hub end closure is secured to the hub prior to installation of the subsea equipment. In the design of a hub end closure, a mechanism for aligning with the hub for installation by an ROV and the interface for the jumper measurement tools should be included. The hub end closure is designed to be recovered or deployed using a lift line and an ROV. In addition, the main sealing area should be protected.
When a pressure-containing end closure is specified, it should meet the following additional requirements:
- The hub closure should have a minimum pressure rating equal to the connector and hub.
- Seal surfaces should be inlaid with corrosion-resistant alloy. The seal surfaces are insensitive to contaminants or minor surface defects.
- The hub closure should be able to be used during subsea equipment hydrotesting.
- The hub should include a provision for a secondary override. If a mechanical pressure cap is used, an ROV jacking tool will be provided to remove the cap from the hub without damaging the hub, piping, or adjacent equipment.
- It acts as a secondary pressure barrier when the jumper is removed and the closure is reinstalled.
- The hub end closure seal may seal on the seal surface used by the connector metal seal.
- It has an inhibitor injection port and pressure relief port operated via an ROV hot stab interface. The design should allow the determination of the internal pressure prior to cap removal and for injection/circulation of inhibitor.
Fabrication/Testing Stands
The fabrication/testing stands should include the following components:
(1) pressure caps and jumper test hubs;
(2) ports for quick, easy hydrotesting of the jumper system after fabrication and assembly;
(3) a removable hub if more than one size of connector is to be tested on the fixture; and
(4) access ladders and work platforms.
The fabrication/testing stands should be designed to satisfy the following items:
- The stand should be capable of being used at a shore base or on the installation vessel.
- The stand should be usable as fabrication/testing or shipping stands.
- It should support the jumper in the installed configuration at the fabrication site or while en route to the installation site.
- It should provide for angular and height adjustments of the mating hubs for jumper fabrication based on field measurements or for modeling misalignment tolerances to verify jumper system functionality.
- It should not limit connector operation and access.
- It should be more rigid than the hub support structures on the subsea equipment.
- It should allow for welding down for transport of a jumper offshore, and quick release of jumper tie-downs offshore during installation. Jumper tie-down release is performed at the deck level.
Transportation/Shipping Stands
They are designed with the following items in mind:
- The stand should support the jumper in the installed configuration at the fabrication site or while en route to the installation site.
- The stand should not limit connector operation and access.
- It should have access ladders and work platforms if required.
- It should allow for welding down for transport of a jumper offshore.
- It should allow for quick, easy release of jumper tie-downs offshore during installation. Jumper tie-down release should be performed at deck level.
- It should be designed to accommodate shipping of different jumper sizes.
- It should allow for the jumper to be transported with a new ring gasket.
- It should use a guide funnel to facilitate installation of a jumper.
Testing Equipment
Testing equipment for jumper fabrication and testing should be configured for offshore use. The test equipment as a minimum includes the following:
- Hydraulic power unit with flying lead, fittings, hot stabs, hydraulic fluid, etc., to operate a soft landing system, connector actuator, and external seal test, or as required to perform a complete test on the jumper connection system onshore;
- Hydraulic water pump capable of achieving the required hydrotest pressure of the jumper system.
Running Tool
The running tool should be capable of installing and retrieving the jumper from an installation vessel with the assistance of an ROV. The running tool is designed to consist of a spreader bar arrangement with lift slings attached to the jumper. Normally, it includes
(1) a ROV- friendly rigging (ROVreleasable shackles) for removal during jumper installation and attachment during jumper recovery (e.g., safety hooks);
(2) jumper lift slings of sufficient length to allow rigging to be attached and ready for lifting and installation with the running tool in the transportation position;
(3) attachment points for steadying lines to facilitate rigging operations; and
(4) guide funnels/guide arms for temporary mounting for contingencies.
In the design of the running tool, the following items should be considered:
- The tool should be able to install and recover the jumper with or without the use of guidelines.
- It should be able to run on drill pipe or lowering crane wire.
- It should not damage subsea facilities during jumper deployment and recovery.
- It should allow for hook up to a jumper.
- It should be configured so that the jumper connector rotation will be minimized during landing of the jumper assembly.
- It should allow for disassembly for truck transportation.
Jumper Measurement Tool
The normal jumper measurement tool includes taut line and acoustics systems. Both systems are utilized when performing subsea measurement of jumpers and the taut line system is utilized for surface fabrication.
Seal Replacement Tool
The metal seal replacement tool should be designed to replace a metal seal without having to bring the jumper to the surface. The operation may utilize the soft landing system and actuator to execute the replacement. The metal seal removal tool positively locks onto the metal seal and extracts it from the connector. The tool protects the extracted seal so that it may be inspected on retrieval.
Hub Cleaning Tool
The hub cleaning tool is used after removal and inspection of the end closure and prior to deployment of the jumper. It consists of a plug with cleaning pads for cleaning debris and grease from the seal surfaces (seal profile) of the
connector hub.
Vortex-Induced Vibration Suppression Devices
The requirement for VIV suppression devices is determined based on a vibration analysis.
ROV-Deployable Thickness Gauge
On each connector end, where erosion is most prevalent, a measurement funnel and plug if required are provided. The arrangement will allow an ultrasonic probe to be installed for reading pipe wall thickness with an ROV at this location. A baseline reading is taken and recorded for each jumper.
References
[1] FMC Technologies, Subsea Tie-In Systems, http://www.fmctechnologies.com/subsea.
[2] T. Oldfield, Subsea, Umbilicals, Risers and Flowlines (SURF): Performance Management of Large Contracts in an Overheated Market; Risk Management and Learning, OTC 19676, Offshore Technology Conference, Houston, Texas, 2008.
[3] G. Corbetta, D.S. Cox, Deepwater Tie-Ins of Rigid Lines: Horizontal Spools or Vertical Jumpers? 2001, SPE Production & Facilities, 2001.
[4] F.E. Roveri, A.G. Velten, V.C. Mello, L.F. Marques, The Roncador P-52 Oil Export System Hybrid Riser at an 1800m Water Depth, OTC 19336, Offshore Technology Conference, Houston, Texas, 2008.
[5] Technip, COFLEXIP Subsea and Topside Jumper Products, www.technip.com.
[6] Cameron, Cameron Vertical Connection (CVC) System, http://www.c-a-m.com.
[7] American Petroleum Institute, Specification for Subsea Wellhead and Christmas Tree Equipment, API Spec 17D (1992).
[8] American Society of Mechanical Engineers, Pipe Flanges and Flanged Fittings, ASME/ANSI B16.5 (1996).
[9] International Organization for Standardization, Petroleum and Natural Gas Industries - Design and Operation of Subsea Production Systems - Part 4: Subsea Wellhead and Tree Equipment, ISO 13628-4, (1999).
[10] B. Rose, Flowline Tie-in Systems, SUT Subsea Awareness Course, Houston, 2008.
[11] American Petroleum Institute, TFL (Through Flowline) Systems, second ed., APIRP-17C, 2002.
[12] E. Coleman, G. Isenmann, Overview of the Gemini Subsea Development, OTC 11863, Offshore Technology Conference, Houston, Texas, 2000.
