1x90 TONS TENSIONERS TECHNICAL PROPOSAL. 1 X 90 Tons 30 m/min Tensioners TECHNICAL PROPOSAL JOB 08/ /02/2008 Basic proposal PP GM SB

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1 Pagina N.: 1 of 19 1 X 90 Tons 30 m/min Tensioners JOB 08/ /02/2008 Basic proposal PP GM SB Rev N Date Issue Description Prepared by Checked by Approved by

2 Pagina N.: 2 of 19 TABLE OF CONTENTS: 1) 90 TONS TENSIONERS 3 1.1) REFERENCES 4 1.2) GENERALS 4 1.3) OPERATING TEMPERATURE 6 1.4) DESIGN LIFE 6 1.5) MANUFACTURING CONTROL PLAN 6 1.6) TECHNICAL FEATURES 7 1.7) CLAMPING SYSTEM/ELASTIC SUSPENSION 8 1.8) ABSORBTION OF PIPE OD VARIATION 9 1.9) OSCILLATING SADDLES ) FRICTION COEFFICIENT ) MOTORS 12 2) INTEGRATED ELECTRICAL PLANT ) INSTALLATION ) STARTERS ENCLOSURE ) CONTROL ENCLOSURE ) MAIN CONTROL DESK ) LOCAL CONTROL DESK ) MONITORING SYSTEM ) AC DRIVES ) CONTROL SYSTEM GENERALS ) AUTOMATION SYSTEM VENDOR LIST 19 3) LIMITS TO THE SCOPE OF SUPPLY. 19 4) DOCUMENTATION. 19

3 Pagina N.: 3 of 19 1) 90 TONS TENSIONERS

4 Pagina N.: 4 of ) REFERENCES Your request 1.2) GENERALS The pipe tensioner has been designed and developed for offshore laying pipes by applying the rated tension up to the max. laying/recovering speed. The tensioner is composed by two tracks vertically mounted, operated by AC electric motors with reduction units, directly connected to the main framework. Encoders allows to control the motor running speed and, therefore, the pipe laying speed, as well as the total and partial length of laid pipe. Pneumatic actuators impress to the pipe the clamping force required to transmit, by friction, the tensioning force to the pipe. Each track is equipped with two chains with cross ties where special oscillating saddles fitted with rubber pads are mounted with the REMACUT quick connecting system, to distribute the pressure evenly on the pipe surface and ensure an adequate coefficient of friction, as required to transmit the pulling force. The saddles/tracks system is supported by a "elastic suspension", consisting of a set of rollers floating on a suspension system, in order to get an even distribution of the clamping pressure on the whole contact surface. Due to the big squeeze system stroke, the tensioner can work in the zone in which the pipe is already curbed. The track squeeze system accepts pipe variation diameters going through the machine without any variation of the squeeze force locally applied, being each roller of the system independent from the others and free to move radially. The radial force applied by the rollers to the track results constant independently from the roller position. This avoids load concentrations on the pipe preserving the integrity of the pipe coatings (concrete, soft insulating coatings etc.). The pipe-saddle contact pressure is so kept at very low values. The upper track positioning is operated by electric motor. Once that the track is positioned correctly with the screw jacks, the squeeze force is applied by operating the constant-pressure pneumatic actuators. The pipe tensioner is secured to the deck structure at the foundation plates by means of bolts that prevent the machine from moving. Load cells are mounted on each track frame. In this way, the pulling force applied by the pipe tensioner during the working stage is continuously measured with a good degree of accuracy, minimising inertia and friction effects and eliminating the errors due to the foundation deflections or irregularities.

5 Pagina N.: 5 of 19 Each tensioner is equipped with load cells with redundant strain-gauges and amplifiers and over-dimensioned in measuring capability to assure the continuous readout of the pull applied.

6 Pagina N.: 6 of ) OPERATING TEMPERATURE Temperature: -10,+45 Humidity: 90%, not condensating 1.4) DESIGN LIFE The machines will be designed for 20 years of operational life. Working cycle is according to Remacut standards for pipe-lay equipment. 1.5) MANUFACTURING CONTROL PLAN Manufacturing control plan as per level 3.1.

7 Pagina N.: 7 of ) TECHNICAL FEATURES The following table summarises the main technical feature of the machine: Nominal continuous tension 90 Ton Peak hold tension 105 Ton Max. speed (pay out and haul in) 30 m/min Max. squeeze force 140 ton each track Min. friction coefficient 0.32 Height (aprox.) 6400 mm Length (aprox.) 7400 mm Width (aprox.) 4230 mm Weight (approx.) 82 Tons B.O.P. (excluding foundations) 1800 mm B.O.P. vertical adjustment stroke (lower +85 mm track) Pipe O.D. diameters (including coating and 4 60 with suitable saddles) Max Vertical opening 2350 mm Electric motor rated power 2x300 kw

8 Pagina N.: 8 of ) CLAMPING SYSTEM/ELASTIC SUSPENSION The tensioner is equipped with a clamping system based on air-springs actuators and an elastic suspension. The function of the elastic suspension is to distribute the pressure evenly on the pipe surface, so that the impressed clamping force results to be correctly distributed on all the saddles. It consists essentially of a chain of plates connected each other but free to move independently perpendicularly to the pipe axis and to follow the pipe external irregularities. The clamping pressure can be regulated setting directly the air pressure in the actuators by using pressure reducing valves. The elastic suspension, pertaining to both the tracks, allows independent motion for each pair of rollers (each saddle) at constant squeeze force. The rollers are free to follow the chain profile so to distribute regularly the clamping pressure also in the event of big external diameter irregularities and to prevent any undesired load concentration on the rollers and on the pipe. The elastic suspension system is separated in sectors that can be singularly enabled - disabled in which the pressure can be set independently. Each sector can be excluded in case of failure without loosing the clamping pressure on the remaining sectors. In case one sector fails, it is possible to increase the clamping pressure on the remaining sectors to guarantee the sufficient friction on the pipe in emergency conditions and prevent the pipe loss or the machine stop. Elastic suspension technical features: Incoming air supply: Bar Max. vertical stroke: + 85 mm each track from the central working point Max. clamping force: Kg. Number of sectors: 4 each track

9 Pagina N.: 9 of ) ABSORBTION OF PIPE OD VARIATION The elastic suspension and springs actuators allows the machine to absorb pipe OD variation keeping constant the local pressure applied to the pipe. This allows the absorption of roughness, stick out, non-weight coated field joints, concrete cutbacks up to the following value: MAX allowed OD variation: +/-150 mm from central working point Anode going through tensioner

10 Pagina N.: 10 of ) OSCILLATING SADDLES The oscillating saddles are the last generation of clamping system developed by REMACUT to extend the working range of the pipe tensioner improving both the performances and the maintainability. The advantages are the following: High contact surface between pipe and saddle rubber pads. This results in a low contact pressure that eliminates all the damages to the pipe coating surface (cracks, deformation, stresses etc.) and allows to work with higher squeeze forces. It is so possible to apply higher pull per each meter of contact length at lower friction coefficient with advantages in both machine length and working condition range. Self aligning to the pipe. As the part of the saddle is free to pivot, it can selfalign the rubber pads to the pipe external surface, so to allow to enter the machine with pipe OD variations within the working range of the mounted set without requiring any adjustment of the saddles Quick substitution of worn pads. To change the worn pads with new ones it require few seconds. It is enough to remove manually (without the need of any tool) a pin to change the complete rubber pad support with one with renewed pads or with one suitable for a different pipe diameter range. This allows to reduce dramatically or eliminate at all the downtime to change worn rubber pads or to set the machine for different pipe OD ranges. Saddles ranges: Fixed saddles: 4-14 Oscillating saddles ranges: / / / 44-60

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12 Pagina N.: 12 of ) FRICTION COEFFICIENT The combination of the elastic suspension together with the oscillating saddles allows the tensioner to work with low friction coefficients:. Min friction coefficient: Tons 1.11) MOTORS Each of the tensioner tracks is driven by 1 AC motors. Features are as follow IP 55 Cooling Forced air by blower Heaters Automatic kick-in when motor is not running Insulation class F

13 Pagina N.: 13 of 19 2) INTEGRATED ELECTRICAL PLANT. The electrical and control system is composed by the following items: 1 Tensioners starter enclosure 1 Tensioners control enclosure 1 central control consolle 1 tensioners local control desks 2 stand-alone AC drives (one drive each motor) 2.1) INSTALLATION AC Drives, Starters enclosure, Control enclosure, Central control consolle shall be mounted in an enclosed and protected area with the following limits: Ambient air temperature: +5 C, +45 c Relative humidity: <95%, non condensating

14 Pagina N.: 14 of ) STARTERS ENCLOSURE It contains the starters for the auxiliary circuits, like motor blowers and screw jacks motors. 2.3) CONTROL ENCLOSURE The control enclosure houses the central rack with the CPU and control cards, plus the power supplies and related breakers required to feed the various I/O stations. The incoming power supply is 230 VAC and can be supplied by the standard network or by an UPS. Using remote I/O philosophy (PROFIBUS DP), the number of power cables, control cables and connections is greatly reduced and also the time to install the machine, lay the cables on the barge and test the wiring. The control system is interfaced with the drives by means of a digital link, for a fast and reliable communication. 2.4) MAIN CONTROL DESK The operator can control and operate all the machine functions from the main control desk. Double scale gauges allow compare easily the pull set point and the actual pull. During manual operation the pipe speed can be controlled precisely by a proportional joystick. From the main control desk it s possible to enable the local consolles. On the control desk is located a Siemens ET200 system ( remote I/O system to reduce number of cables). The main control desk is equipped with one touch screen panel. 2.5) LOCAL CONTROL DESK The local control desk is designed in order to control the basic machine functions in manual mode, for maintenance or initiation.

15 Pagina N.: 15 of ) MONITORING SYSTEM The status of the machines can be monitored through a specifically developed monitoring system. Below some samples of the monitoring system pages FIG. 2-1 Tensioner monitor page Tension load, laying speed and clamping pressure are displayed both in digital and bar chart form. The LAYED PIPE length is displayed in digital form. The window shows also the operating status of the machine (MANUAL/AUTOMATIC, SUSPENSION ON/OFF, DEAD BAND ON/OFF, SLAVE/MASTER etc.).

16 Pagina N.: 16 of 19 FIG Tensioner drive monitoring page This is a display only page used to monitor the tensioner motors drive. The upper part of the window shows the speed and the torque of each motor. The lower part shows the temperature and and some leds that recalls the operating status (brakes, enabled, etc..)

17 Pagina N.: 17 of ) AC DRIVES Each motor is driven by an independent AC drive, featured as follow: Incoming voltage: 460 V 60 Hz Drive technology: Active Front End Index of protection: IP22 Operating temperature: 5-45 C Cooling: forced air Current THD: < 5%

18 Pagina N.: 18 of ) CONTROL SYSTEM GENERALS The tensioners can be controlled in manual mode (speed mode) or in automatic tension control. When in manual, the tensioners speed is controlled by means of a proportional joystick. The operator can control each tensioner independently from the local control desk or can insert on line the tensioners and control them in common mode (1 master joystick controls all the tensioners) from the main control desk. For maintenance tasks, the operator can choose whether to operate with the lower track, with the upper track or with both. When in automatic mode, the operator can set a common set point for the pipeline and the control system will keep the tension at the desired value. It is also possible to set the load sharing percentage on the machines. A dead band mode can be selected, in order to keep the pipe steady during the welding phase. In case a particular deceleration is required at the barge stopping, the operator can insert the dead band mode. The control system evaluates the amount of pipe laid since the dead band insertion and brings the pipe back to the insertion point (position control with tension control override). The control is designed in order to allow the insertion/removal of one tensioner from the line without stopping the automatic mode on the remaining machines. The system is design for future integration with Remacut A/R winches.

19 Pagina N.: 19 of ) AUTOMATION SYSTEM VENDOR LIST Drives: Siemens, ABB PLC: Siemens Enclosures: Rittal Stainless steel enclosures: Irinox, Rittal Starters, Breakers, power supplies: Siemens 3) LIMITS TO THE SCOPE OF SUPPLY. Erection on site, installation, commissioning, testing and sea trials are not included in the scope of supply. Interconnection piping and cables are not included in the scope of supply Oil, fluids and lubricants are not included in the scope of supply Foundations are not included in the scope of supply. Tools, hooks, greenpins, ropes, for machine erection, installation, testing and calibration are not included in the scope of supply 4) DOCUMENTATION. Technical manuals and as-built dossier in English, 3 copy on CD Rom.