EAB ENGINEERING SOFT LANDING CYLINDER. Impact dampers for installation of structures subsea.

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1 EAB ENGINEERING SOFT LANDING CYLINDER Impact dampers for installation of structures subsea.

2 PRODUCTION DESCRIPTION TECHNICAL INFORMATION MAIN SPECIFICATIONS Initial lowering velocity: up to 0,5 m/s (typical)* Velocity end damping: down to 0.02 m/s ** Deceleration: Typical: 0,5 1,0 G Damping travel length: 200mm Lowering travel length: 70mm or 300mm Response to heave motions: Close to 1G The EAB Soft Landing Cylinder is an impact damper helping to reduce the impact load when landing structures subsea. The Soft Landing Cylinder also secures that the final touchdown speed is not exceeded in case of failure of the heave compensation system. The EAB Soft landing Cylinder is using seawater as working medium and damping is achieved by throttling sea water through a pattern of holes in the cylinder wall. The cylinder fills up automatically with seawater when submerged and does not need to be connected to any external system, hydraulics or accumulators. The system can be used at any depth without pre-adjustment. No limit Design life: Based on material selection Carbon Steel Top side outdoor: preserved for 1 year Submerged: Single installation (unlimited landing attempts) Duplex/SuperDuplex Top side outdoor: Unlimited Submerged: 20 years * higher velocities is possible (to be determined by detailed calculations in each case) ** limited by minimum hole size achievable Through the special throttle pattern developed and sized for each application, the damping force is maintained relatively constant over the stroke and large dynamic peaks are avoided. Typical peak retardation values are 0.5 to 1.0 G. The cylinder has full response to heave motions (close to 1G) achieved by the unique patented piston design allowing for high flow at low resistance through the piston when the piston is moving down. No springs are used, and it does not represent any danger to personnel, compared to spring loaded cylinders. The most common applications are for running tools and smaller modules designed for a landing velocity typically 1.8 m/s - and larger modules weighing up to 360Te designed for a typical landing velocity of 0.5 m/s. The cylinders are designed to withstand lateral loads caused by angular offset and/or friction from sliding. Water depth: Full sealing to pressure when the piston is moving upwards The piston is short circuiting when stroking out, and piston and rod fall down and follow the heave motion (patented)

3 CYLINDER OPTIONS SELECTION OF CYLINDER The EAB Soft Landing Cylinder comes in a range of standard sizes and configurations. Selection of the right cylinder size for a given application is based on: Location of CoG (symmetrically related to the cylinders) Landing speed Steel mass Added mass (drag) Trapped water Angular offset (tilting) (EAB default: 2,5 ) Friction coefficient between piston rod and base structure (EAB default: 0,2) No. off cylinder to be used (max. 4 off recommended) Soft Landing Cylinder options: Cylinder models from SL90 to SL230 Top flange or bottom flange mounting With/without bucket With/without transport security Threaded/clearance holes in the flange Cylinder housing material: Carbon Steel, Duplex and Super Duplex 270mm and 500mm stroke (500mm for bottom flange only) Diagram 1 and 2 can be used for selecting the appropriate cylinder size based on a landing speed of 0,5 m/s and default values for angular offset and friction. MOUNTING Select between top flange or bottom flange mounting Note: the cylinder size selected will always be verified by EAB before any PO is accepted. Small series model options: SL90, SL115, SL140, SL180, SL230. For larger models, see the Large Series brochure. TRANSPORT SECURITY A safety/locking pin to secure the piston in the upper position can be included BUCKET A surrounding bucket can be mounted around the cylinder housing to keep the unit water filled during topside testing/air usage. 2,5 Landing speed (before damping) MATERIALS For repeated use, cylinders with Duplex or SuperDuplex housing is recommended. For single installations, cylinders with carbon steel housing is the most cost efficient option. Selection of cylinder size Landing speed vs steel mass 2 SL90 SL115 SL140 SL180 SL230 1,5 1 0, Steel mass (in air) Diagram 1: Cylinder selection based on given landing speed and steel mass. 120

4 MAIN DETAILS STANDARD CYLINDERS TOP FLANGE AND BOTTOM FLANGE W/270 MM STROKE Steel mass in air (T) Selection of cylinder size Steel mass vs added mass at 0,5m/s landing speed SL230 SL90 SL115 SL140 SL180 SMALL SERIES, SL90-SL230 Added mass (T) Diagram 2: Cylinder selection based on a landing speed of 0,5 m/s, steel mass and added mass (small series). EAB Type w/270 mm stroke SL90/70x200 SL115/80x200 SL140/100x200 SL180/120x200 SL230/150x200 Weight 49 kg 64 kg 78 kg 134 kg 195 kg Weight w/bucket 58 kg 75 kg 98 kg 150 kg 215 kg Typical range - 16 T T T T T MAIN DETAILS STANDARD CYLINDERS BOTTOM FLANGE W/500 MM STROKE EAB Type w/500 mm stroke SL90/70x200 SL115/80x200 SL140/100x200 SL180/120x200 SL230/150x200 Weight 60 kg 83 kg 102 kg 177 kg 258 kg Weight w/bucket 74 kg 96 kg 125 kg 198 kg 284 kg Typical range - 16 T T T T T

5 DIMENSIONS TOP FLANGE, 270MM STROKE DIMENSIONS BOTTOM FLANGE, 270MM STROKE DETAILED DIMENSIONS TOP FLANGE, STANDARD SL90 SL115 SL140 SL180 SL230 A Ø220 Ø260 Ø300 Ø320 Ø400 B C D Ø60 Ø80 Ø100 Ø120 Ø150 E F G M20 M24 M24 M24 M30 H PCD 180 PCD 210 PCD 250 PCD 270 PCD 350 I Ø114 Ø141 Ø168 Ø219 Ø273 J Ø206 Ø219 Ø306 Ø306 Ø364 MAIN DETAILS STANDARD CYLINDERS TOP FLANGE AND BOTTOM FLANGE W/270 MM STROKE SL90 SL115 SL140 SL180 SL230 A Ø300 Ø300 Ø300 Ø370 Ø420 B C D Ø60 Ø80 Ø100 Ø120 Ø150 E F G Ø22 Ø22 Ø27 Ø33 Ø33 H PCD 250 PCD 250 PCD 250 PCD 300 PCD 350 I Ø114 Ø141 Ø168 Ø219 Ø273 J Ø206 Ø219 Ø306 Ø306 Ø370

6 DIMENSIONS BOTTOM FLANGE, 500MM STROKE MATERIALS AND SURFACE TREATMENT The following materials and coating are standard Part Material Coating Cylinder housing MDS Y 05/Y 07 (Carbon Steel) MDS D 41/D 45 (Duplex) MDS D 51/D 55 (SuperDuplex) Outside: NORSOK M-501 system 7b Inside: XYLAN 1424 Outside: NORSOK M-501 system 7b Outside: NORSOK M-501 system 7b Cylinder Rod Xylan 1424 Piston MDS K-02 (Al.Bronze) None End bushing, Gland MDS K-02 (Al.Bronze) None Bearings Orkot 380 Marine bearing Bucket, barrel MDS S-01 (AISI 316L) NORSOK M-501 system 7 If the damper is intended to be operated repeatedly: Housing in Duplex or Super Duplex is recommended. ORDER FORM SLxx yyy mm ff t b - ts Drawings and 3D models (STEP) available on request. Code Description Options Comment xx Cylinder size 90, 115, 140, 180, 230 yyy Stroke 270, 500 Available stroke length in mm mm Material CS, D, SD CS: Carbon steel D: 22 Cr. Duplex SD: 25Cr. Duplex ff Flange TF, BF TF: Top Flange BF: Bottom Flange t Flange hole T, C T: Threaded hole C: Clearence hole b Bucket 1, 0 1: With Bucket 0: Without Bucket ts Transport Security 1, 0 1: With Transport Security 0: Without Transport Security DETAILED DIMENSIONS CYLINDER BOTTOM FLANGE MM STROKE Customer specific version of the EAB Soft landing Cylinder can also be supplied. Please contact EAB for information. SL90 SL115 SL140 SL180 SL230 A Ø300 Ø300 Ø300 Ø370 Ø420 B C D Ø60 Ø80 Ø100 Ø120 Ø150 E F G Ø22 Ø22 Ø27 Ø33 Ø33 H PCD 250 PCD 250 PCD 300 PCD 300 PCD 350 I Ø114 Ø158 Ø190 Ø219 Ø273 J Ø206 Ø219 Ø306 Ø306 Ø370

7 EAB Engineering AS Studieveien 16 N-2815 Gjøvik Norway Phone: