W I N C H E S

Underwater Fairleads

Chain Tensioners

SPREAD MOORING EQUIPMENT

Chain Tensioner CharacteristicsThe SAS double, inverted cylinder “PUSH” style,

reciprocating, vertical acting Linear Chain Tensioner

(LCT) is a fixed style, intended for applications where

one permanent tensioner per mooring leg is required.

The integral primary chain stopper is designed to

withstand the full Minimum Breaking Load of the chain

without damage.

The primary chain stopper arrangement supports and

aligns the tensioning cylinders and is intended for a

bolted connection to a customer designed and supplied

foundation. All tensioners will be supplied with full product

certification by Classification societies such as DNV or ABS.

Tensioners will carry Design Review Approval and FAT Witness

Certificates from the designated Classification Society.

BenefitsThe SAS Linear Chain Tensioner technology has evolved

from 45 years of experience and know-how in the design

and manufacture of offshore pipe-lay tensioners com-

bined with more recent experience and familiarity in the

field of Spread Mooring Equipment for Offshore Produc-

tion Platforms. In addition to our already comprehensive

product line has been designed from the ground up by first

applying innovative design to improve existing technology,

materials and manufacturing methods then seeking and

implementing customer input to optimize installation and

operation based on field experiences.

The philosophy behind our approach is to offer a product that:

• Is user friendly with functional simplicity and long-term

reliability

• Does not require additional below deck support structure

• Requires low maintenance with minimal set-up

• Does not incorporate complex and sensitive operating

technologies

• Minimizes investment and operational costs

Modular ConceptIn order to minimize front-end engineering and optimize

delivery lead time, SAS Linear Chain Tensioners are offered

in 9 standard modules each based on a chain size range.

These standard modules are outlined in tabular form overleaf

and cover mooring chain sizes between 100 and 180mm.

Of course models covering chain sizes above and below this

standard range are also available.

Product ConfigurationsAlthough SAS has opted for the simpler and more straight-

forward “PUSH” style of tensioner for our base product

range, other styles and configurations are available:

• Deck penetrating “PULL” vertical style where low

overhead clearance is available

• Movable vertical tensioner with integral primary stopper

• Movable vertical tensioner with integral secondary

stopper – separate primary stopper

• Fixed horizontal tensioner / stopper combination

• Movable horizontal tensioner with separate primary

stopper

Additional ProductsIn addition to our Linear Chain Tensioner line, SAS offers

a comprehensive range of mooring and installation

equipment:

• Riser Pull-In and Mooring Line Installation Rotary Drum

and Traction Winches

• Installation and Line Tensioning Chain Winches

• Vertical and Horizontal Windlasses

• Underwater Chain Fairleads and Wire Rope Sheaves

• Overboarding Chutes and Chain Guides

• Underwater Combination Swivel Fairlead – Primary Chain

Stopper (under development)

ApplicationsSAS equipment can be configured to suit the particular

requirements of the full spectrum of offshore production

vessels and platforms:

• Mono-Hull FPU and FPSO

• Ship-Shape FPU and FPSO

• Standard and Deep Draught Semi-Submersible FPU

• Seagoing Platform (SPAR) type FPU

• Classic, Truss or Cell Type SPAR

Standard Features • Rugged Modular Construction

• Load Path Custom Designed to Suit Deck Structure

• Non-Corrosive Stainless Steel Primary Stopper

• Load Pin Replacement under Full Line Tension

• Ratchet Style Self-Closing Pawl Action

Control Features• PLC based with Local (Station) Control Console

• Self Synchronizing Hydraulic Tensioning Cylinders

• Fully Sealed – Zone Rated HPU and LCT Control Console

• Multi-Mode Operator Selectable Control Functions

• Continuous Load Monitoring

Reliable Spread Mooring Systems

Linear Chain Tensioners

Push Type LCT range

www.saswinches.nl

Chain

diameter

mm.

Pre

tension

kN

Stall

tension

kN

Speed

in/out

m/min

MBLPrimarystopper

Based on Chain R4S

kN

Hydraulic PressureWorking condition

Hydr.eff. 0,85Stall condition

HydraulicFlow

Based on real stroke

liters (gal.)

Dimensions

in meter

Weight

in

ton H W Df

LCT-PH0007

100102105107

2167224523632442

2600269328352931

2,002,002,002,00

12335

176 (2552)182 (2643)192 (2782)198 (2876)

207 (3002)214 (3110)226 (3273)233 (3384)

248 (3603)257 (3732)271 (3928)280 (4061)

248 (3603)257 (3732)271 (3928)280 (4061)

50,593 (13,366)51,422 (13,585)52,874 (13,968)53,91 (14,242)

LCT-PH1117

111114117

260427282854

312532743425

1,751,751,75

14415211 (3067)222 (3213)232 (3361)

249 (3609)261 (3780)273 (3955)

254 (3681)266 (3856)278 (4034)

299 (4330)313 (4537)327 (4746)

55,984 (14,79)57,435 (15,173)58,887 (15,557)

Contact SAS

Contact SAS

Contact SAS

Contact SAS

Contact SAS

Contact SAS

2.95

3.10

3.50

3.60

4.05

4.25

10

13

16

19

23

28

2.00

2.15

2.35

2.50

2.72

2.94

1.15

1.25

1.37

1.46

1.59

1.70

LCT-PH3037

130132137

341835073733

410142094479

1,501,501,50

18852212 (3082)218 (3162)232 (3366)

250 (3626)257 (3720)273 (3960)

255 (3698)262 (3795)278 (4039)

300 (4351)308 (4465)328 (4752)

86,866 (22,948)88,24 (23,311)91,539 (24,182)

LCT-PH7175

171172175

533653795530

640464556636

1,001,001,00

27930212 (3080)214 (3104)220 (3191)

250 (3623)252 (3652)259 (3755)

255 (3696)257 (3725)264 (3830)

300 (4348)302 (4383)311 (4505)

181,875 (48,047)182,752 (48,278)186,258 (49,204)

LCT-PH7780

177178180

562756765773

675368116927

1,001,001,00

29155224 (3247)226 (3275)230 (3331)

263 (3820)266 (3853)270 (3919)

269 (3897)271 (3930)276 (3998)

316 (4585)319 (4624)324 (4703)

188,449 (49,783)189,325 (50,015)191,517 (50,594)

LCT-PH4247

142147

39624193

47545032

1,501,50 21179

195 (2822)206 (2988)

229 (3321)242 (3515)

234 (3387)247 (3585)

275 (3985)291 (4218)

121,392 (32,069)125,614 (33,184)

LCT-PH5257

152157

44284665

53135598

1,501,50 23559

218 (3155)229 (3323)

256 (3711)270 (3910)

261 (3786)275 (3988)

307 (4454)323 (4692)

129,836 (34,299)134,059 (35,415)

LCT-PH2027

120122124127

2982306831543285

3578368137853942

1,501,501,501,50

16592

185 (2689)191 (2766)196 (2844)204 (2962)

218 (3163)224 (3254)231 (3346)240 (3485)

222 (3226)229 (3319)235 (3413)245 (3555)

262 (3796)269 (3905)277 (4015)288 (4182)

80,268 (21,205)81,368 (21,495)82,742 (21,859)84,666 (22,367)

LCT-PH6268

162165167168

4903504751435192

5884605761726230

1,251,251,25 1,25

26221

195 (2830)201 (29113)205 (2968)207 (2996)

230 (3329)236 (3427)241 (3492)243 (3525)

234 (3396)241 (3495)246 (3562)248 (3595)

275 (3995)284 (4112)289 (4190)292 (4230)

172,672 (45,615)175,74 (46,426)177,493 (46,889)178,807 (47,236)

Cylinder port

Cylinder port

bar (psi) bar (psi) bar (psi)

System incl. hydr. eff.

System incl.

hydr. eff.

SAS

Model

ref. bar (psi)

Fixed LCT

W WDf Dm

Movable LCT

Chain Tensioner Unique Design Features

-E- The structurally stiff, high tensile steel

casting crosshead is operated by two

mechanically synchronized hydraulic cylinders

such that no complex, sophisticated,

electronic motion control equipment is

required. This renders the SAS system user

friendly, offers ease of operation and

simplified set-up and maintenance.

-F- The custom designed, marine quality hydraulic

cylinders are rigidly flange and spigot mounted to

the stopper frame. The rod ends are

fitted with a shrink fit insert bushing that has a tight

location fit in the traveling crosshead. There are

no stressed threaded connections or

compliant joints that present possible

failure points or require maintenance.

-G- The primary stopper pawls and their

base inserts are precision machined from

high tensile stainless steel castings to

prevent corrosion over the life of the

equipment. As the pawls lay flat at 90°

to the chain center line a very stable

foundation is provided with the

induced mooring loads transferred

from the critical chain link through

the stopper and insert over a

wide flat surface.

-A- Tensioning of the chain is performed using a

traveling crosshead fitted with two horizontally

opposed ratchet type pawls engaging the lower

radius of the chain link. Each pawl is offset

from the chain center line at an angle of 45°

and pivots on a high tensile stainless steel

shaft centered in the load path to effectively

direct the applied tensioning load through the

crosshead casting and into the cylinder rod ends.

-B- The two-part stopper arrangement has its

load sensing base bolted to the customer

supplied foundation. The stopper frame is

supported on the stopper base at four locations

each with a load sensing pin. The longitudinal

centerlines of the load pins are designed to

match the under deck support structure frame

centers such that the mooring loads are directed

directly into the deck structure without the need

for additional support webs and gussets.

-C- The primary stopper pawls act at 90° to

the chain centerline and engage on the lower

radius of the critically loaded chain link. The

ratchet style pawls lay flat on their locating

base to distribute the induced mooring loads

over a wide area. Both the pawls and

locating bases are manufactured from high

tensile stainless steel to resist corrosion

over the life of the equipment.

-D- A below deck, cruciform shaped, chain

entry guide is provided to orient and align

the chain for correct passage into the LCT.

This unit is bolted to the underside of the

main or mooring porch deck between the

vertical support members.

-H- The entire LCT is mounted on an

array of 4 instrumented load pins

installed between the stopper frame

and stopper base with the base being

configured for a bolted connection to the

vessel deck foundation. This arrangement

provides continuous load monitoring either during

chain tensioning or under mooring loads.

Underwater Fairleads

Underwater Fairlead Unique Design FeaturesThe SAS Underwater Swivel Fairlead is a conventional

design flagging style, direct hull mounted unit,

incorporating a seven pocket European style cast steel

wildcat. The flagging arm pivots between upper and lower

mounting brackets welded directly to specially prepared

hull longitudinal stringers and vertical frame members.

Installation and MaintenanceUpper and lower mounting brackets are manufactured as

welded fabrications or precision castings using steel that is

fully compatible with hull plate material. Once the brackets

are installed they become a permanent integral part of the

hull structure. Special installation tooling is provided to

ensure correct hinge pin bore alignment is set and

maintained between the upper and lower brackets during

welding.

Although designed for the full rated vessel life, the fairlead

is configured to allow removal / replacement of the wildcat,

or entire flagging frame, from its submerged station using

ROV intervention either with or without diver assistance.

The mooring line tension can be temporarily retained

during this maintenance exercise but tension must be

released from the deck mounted primary stopper.

Wildcat and Flagging Frame:The wildcat is a single piece high tensile steel casting with

precision cast pockets designed to support the links on

individual pads. This feature provides a more stable and

uniform support of the critically loaded horizontal links and

reduces the effects of Out-of-Plane Bending (OPB), a major

cause of link failure. The wildcat rotates on a high tensile

stainless steel spindle running in low friction, seawater

lubricated journal bearings. The precision cast pocket

configuration and low breakaway torque provided by the

non-metallic journal bearings reduce the tendency for the

links to slip during their passage through the fairlead or

when under full modulating load with hull yaw, pitch

and roll.

The flagging frame is mounted on high tensile stainless

steel shafts operating in low friction seawater lubricated

journal bearings and thrust plates. The extremely low

break-away friction of these bearings when under full

design load reduces Out-of-Plane Bending (OPB) of the first

critically loaded vertical links directly adjacent to the wildcat

where the chain exits the fairlead on the anchor side.

Surface Protection:The surfaces exposed to seawater are specially prepared

and finished with an application specific, highly durable

paint system completed with an anti-fouling top coat to

minimize marine growth. Unfinished exposed surfaces and

components are manufactured from seawater corrosion

resistant, high tensile stainless steel.

Bearings:All bearings are journal type with load bearing thrust plates

where required all of which are manufactured from a high

compressive strength, non-metallic, filament wound,

maintenance free material suitable for lubrication by

seawater. Visual or electronic bearing wear indicators can

be provided as an option.

Operating Criteria:The fairlead is designed to withstand, as a minimum,

the minimum breaking strength (MBL) of the chain or other

loading for the mooring leg as designated by the Client.

Horizontal displacement (azimuth) is ±80° either side of a

neutral position perpendicular to the hull or column side

shell with a vertical displacement (pivot) from 10° to 80°

down from the horizontal. The maximum load condition is

generally considered as between 45° and 60° down from

the horizontal (or as specified by the client). Loads outside

of this range are considered as installation loads unless

designated as required survival loads by the Client.

www.saswinches.nl

HEAD OFFICE

SAS Winches B.V.Bedrijfsweg 23-252404 CB Alphen a/d RijnThe Netherlands

info@saswinches.nlwww.saswinches.nl

BRANCH OFFICE

SAS USA Inc.757 North Eldridge Parkway, Suite 675Houston, TX 77079USA

jal@saswinches.com+1 (832) 477-2979 ehu@saswinches.com+1 (832) 421-6803

W I N C H E S