sas lct brochure
DESCRIPTION
A digital version of the brochure: SPREAD MOORING EQUIPMENTTRANSCRIPT
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
BRANCH OFFICE
SAS USA Inc.757 North Eldridge Parkway, Suite 675Houston, TX 77079USA
[email protected]+1 (832) 477-2979 [email protected]+1 (832) 421-6803
W I N C H E S