CBMs/SPMs

Bill Davies
22nd April 2009, 23:22
Would be interesting to hear the members views on the subject modes of mooring. CBMs: Halul (now Mesaieed) / Jebel Dhanna comes to mind. SPMs: countless. If you were not careful in Jebel Dhanna you would be lucky to get out without some mishap.

Bill Davies
22nd April 2009, 23:26
For our enthusiast members:
CBM: Conventional Buoy Mooring
SPM: Single Point Mooring (often referred to as SBM: Single Buoy Mooring)

Orbitaman
23rd April 2009, 06:19
The term SPM sprang into existence when a company registered SBM as their company name. Still located in Monaco and probably the world leaders in turret moored FPSO technology.

Bill Davies
23rd April 2009, 08:52
The approach speed is critical on either of the above and it would be interesting to hear from Masters on whether the Pilots over use of Nav aids on approach did anything for their confidence. I noticed a marked change, since the 90s, when the over reliance on these devices was evident and certainly did nothing for my confidence. What has happened to the art of 'using ones eyes'.

Bill

RayJordandpo
23rd April 2009, 09:48
I don't know about mooring to one but laying close alongside SPM's/SBM's could be a pain. I was on a DP vessel contracted to carry out maintenance including dive operations on one. It is easy to forget that the things are always on the move. We would just get set up on DP a few metres from the buoy with the vessel stabilised and divers in the water when the thing would come hurtling towards us, you had to be really on your toes.

Another occasion I was on an Indian dive support vessel working Bombay High Oil Field, we often got the task of changing out the hoses on the SBM's, no mean feat but I must say the Indian boys had it off to a tee and knew exactly what they were doing. They used air divers or just "swimmers" and they would come on deck covered in crude oil, God only knows what their lungs were like.

I can't say I have fond memories of SBM's. Some years ago (1982) I was skipper of a supply boat in the Middle East. It was middle of the night and the Indonesian mate was on watch. We were steaming towards Halul Island when there was an almighty crash and the ship came to an abrupt stop. He had managed to run over an SBM floating hose, said the light on the end was unlit, well if not it certainly was when we had finished with it. The hose was well jammed underneath the vessel and it took hours to free it using a deck crane and some very 'gingerly manoeuvring' We got away with a couple of scrapes and a tipped prop blade, luckily I had an understanding boss

BlythSpirit
24th April 2009, 10:08
Would be interesting to hear the members views on the subject modes of mooring. CBMs: Halul (now Mesaieed) / Jebel Dhanna comes to mind. SPMs: countless. If you were not careful in Jebel Dhanna you would be lucky to get out without some mishap.

Bill - Halul is an island off Qatar, what is now referred to as Mesaieed was the Qatari port, previously known as Umm Said.

Bill Davies
24th April 2009, 10:33
Correct!

Steve Woodward
24th April 2009, 10:42
An amusing approach to an SBM from quite a few years ago.
No names of port or ship so no pack drills!

Ship : shuttle tanker 120k with a bow manoeuvring house ( close manoeuvres carried out from bow rather than wheelhouse aft) on approach to SBM the Captain and Pilot etc. decamp from wheelhouse to bow-house having switched the controls to the bow-house. On arrival at bow house it was found to be locked, furthermore the key was aft (in the Wheelhouse I believe) at a sizeable speed the ship hit the SBM followed by, presumably, a certain by-product hitting an air movement device.
OOOPS

sidsal
24th April 2009, 11:42
Steve's little story would be hilarious were it not for the implications. Your stories of SBMs etc are very interesting to one who never knew them when in tankers years ago. However when in Brocklebanks years ago there was a story of a turbine driven ship of theirs berthing in New York - in one of the bays upriver from where the Queens berthed. The US pilots were more gung-ho than their British counteraparts and would approach a berth quite fast and then go full astern. On this occasion they approached the berth and then the pilot ordered full astern and said to the master- "She IS a reciprocating engine, isn't she ?" The master said - "No - steam turbine"
"Sh**" said the pilot as the astern power which was about a third of that of a reciprocating engine which has equal power astern or ahead - as the ship crunched into the dock wall and severely bent the stem.

ray bloomfield
26th April 2009, 23:51
I dont know how you guys did it on big ships, but I do know how we used to tie up to '''SBM's''' when I worked on the barges in the Thames. The skipper used to put the bow alonside the bouy and I (as mate, and only other crew member,) used to drop down on to the bouy with the rope, put it thru the ring, throw the end back on board and quickly clamber back and make it fast. Piece o' cake when loaded but could be tricky when MT.

Bill Davies
24th May 2009, 09:57
That's a very interesting post Ray. Many thanks

Bill

greektoon
27th May 2009, 14:24
And on a conventional buoy mooring NEVER sling the eye on the bits.

Bill Davies
27th May 2009, 16:16
And on a conventional buoy mooring NEVER sling the eye on the bits.

You have lost me. Please explain.

Steve Woodward
27th May 2009, 16:57
Bill,
I think greektoon means that when passing a slip rope through the eye on a buoy do not put the eye on the bits but turn it up so that it can be readily slipped without having to pull slack rope back on board to lift the eye off.


Another minor mishap on a Monobouy : again no names / ports so no pack-drills.
Modern shuttle tanker moored to an SBM by a single chafe chain - normal practice.
cargo is being discharged via two 16" hoses at the port manifold - again normal practice.
Officer of the watch in relaxed mode in the control room stretches out contentedly knowing all is well and puts feet up on the control consul, one heel comming down on the emergency disconnect button for the bow stopper, bow stopper releases mooring, ship promptly drifts back parting hoses -oops
Steve

joebuckham
27th May 2009, 16:58
And on a conventional buoy mooring NEVER sling the eye on the bits.

when involved in mooring or being towed we were taught never to put an eye directly on the bitts

ray bloomfield
27th May 2009, 23:55
Would not using the bare end be better, then there is no eye to inadvertently get hooked on to anything when throwing it off?

greektoon
28th May 2009, 06:54
You have lost me. Please explain.

I should have expanded Bill.

Steve is correct. When letting go from the buoy, it may not be easy to get enough slack to lift the eye of the rope off the bitts due to the stern drifting. This happened to me when I was second mate on a ship moored on the buoys at Rotterdam. If the free end of the rope is turned up on the bitts, then it can be slipped no problem.

greektoon
28th May 2009, 07:03
Bill,
I think greektoon means that when passing a slip rope through the eye on a buoy do not put the eye on the bits but turn it up so that it can be readily slipped without having to pull slack rope back on board to lift the eye off.


Another minor mishap on a Monobouy : again no names / ports so no pack-drills.
Modern shuttle tanker moored to an SBM by a single chafe chain - normal practice.
cargo is being discharged via two 16" hoses at the port manifold - again normal practice.
Officer of the watch in relaxed mode in the control room stretches out contentedly knowing all is well and puts feet up on the control consul, one heel comming down on the emergency disconnect button for the bow stopper, bow stopper releases mooring, ship promptly drifts back parting hoses -oops
Steve


Is a remote emergency disconnect arrangement mandatory or a requirement at some terminals? I am not familiar with this.

Steve Woodward
28th May 2009, 17:54
GT
Shuttle tankers have it for disconnecting from rigs off-shore in the North Sea, it should stop the rigs transfer pumps by telemetry, then close the bow loading gear and then let go the mooring.

Jay Wye
2nd June 2009, 20:36
No names, no pack drill, but when I was a Pilot on the Jebal Dhanna CBM's, the odd tanker would arrive with an honest Master--"Mr Pilot, the brake on the starboard windlass no good!"
I remember a couple of points from my Master's orals, you do not drop anchors at 2 knots, -- we did on VLCCs! Especially in 20+knots beam wind! You also did not walk out anchors at around one knot, we did in the previously mentioned wind speed with u/s brakes!
And hey, it worked. That was before we got the tugs, then, --berthing became almost easy!
So you dropped or walked out both anchors, backed into the berth, and then the Beddu boat crew left you. "Wachid Hawa" (Too much wind). Ah, the good old days, and they think they have it difficult on SBMs.

Naytikos
7th June 2009, 08:25
A company I worked for built a new VLCC and, having taken advice from ARAMCo specified a Smit bracket on the forecastle especially for Juaymah. Two years later, on the first trip to that terminal the mooring assistant (or whatever he was called that week) went forward and called the pilot in the wheelhouse to say the ship could not berth because there was no chain stopper! 'Oh yes', said the latter, 'They changed the requirements about a year ago; Smit brackets are out, chain stoppers are in'!
We did moor in the end and never heard any more about it on subsequent trips.

Bill Davies
7th June 2009, 10:18
Reflecting on several of the posts above. I am not altogether sure that some contributors are not confused over the terminology!

Jay Wye
28th July 2009, 08:56
Bill, clarify, what do you mean or what are you saying?!

Bill Davies
28th July 2009, 09:25
Jay Wye,
Many thanks yours.
Clarify in what respect? Are you asking whether certain contributors have misunderstood what exactly CBMs/SBms are or Incidents which may/can happen whilst berthing?

McCloggie
28th July 2009, 10:29
Just to clarify what an SPM is:

SPM of course stands for Single Point Mooring which, technically, can also include mooring towers. The systems allow a vessel to be moored (and load/discharge) via a single connection as opposed to a CBM which will require the vessel to be moored within a pattern of a number of conventional buoys.

What is being talked about here are CALM (Catenary Anchor Leg Mooring) buoys which are also SPMs. The system allows a vessel to moor/load/discharge via a single buoy and rotate around the buoy in response to the environmental factors.There are two types of CALM buoys:

The traditional Turntable Buoy - initially developed (originally for the Swedish Navy) with a moored buoy body on top of which a turntable (with the mooring lugs/unijoints) mounted on bogie wheels which can rotate through 360 degrees. The bogie wheel variety have virtually all been replaced by turntables mounted on three race roller bearings (although some slide bearings have also been used).

The Turret Buoy - Here, a cylindrical mooring "turret" is retained to the seabed (anchors or piles) and the buoy body is mounted on the bearing and rotates around the fixed turret. The main advantages of this arrangement is that the swivel and bearing are protected, maintainance is safer (inside the deckhouse and no rotating turntable over the buoy deck) and should the buoy be "kissed" it is the body and not he turntable that is hit. Bluewater invented/provide the Turntable Buoys.

The method of mooring/unmooring to/from a CALM buoy is the same whether a turntable or turret buoy is used although clearly the methods for specific buoys will differ depending on locations, conditions, availability of tugs product requirements etc.

At Bluewater, we based our procedures on the OCIMF guidelines and for as long as I have been involved in the game (with both Bluewater ans SBM) Chaffe Chains have been provided at both ends of the mooring hawser(s). In some cases, you can provide different sizes of chains on the tanker end of the hawser allowing vessels of different size to use the facility. It must be remembered though that it is not a simple one-size-fits-all solution as the buoy body size may vary and the buoy anchoring arrangements (usually a chain-wire rope-chain arrangement) may also vary.

McC

Bill Davies
28th July 2009, 10:32
Very good McCloggie, can you please advise what a CBM is?

McCloggie
28th July 2009, 10:44
Hi Bill;

CBM is a Conventional Buoy Mooring. Usually used in shallow/shelterd water for small vessels and barges.

The buoys are normally set out in a pattern - two for the stern and maybe one or two for the bow ropes but it could vary. The tanket is positioned within the pattern and being moored fore and aft does not rotate is response to the environmental factors and so no fluid swivel is required.

Loading/discharging is achieved usuually through a hose laid out on the sea bed which is picked up via a pennant/buoy arrangement by the tanker midships crane and attached to the midships manifold.

The buoys that I have worked on have been smaller than CALMS and are fitted with quik release hooks allowing the tanker to arrive/depart with the minimum of assistance but you still need to have a man on the buoy for the connection as the tanker's mooring ropes/wires are used (which of course is not required for a CALM arrangement with a floating hawser).

In some ways a CNM is like a normal berth but without the jetty!

I have seen CBMs in Sri Lanka, UAE (for a power station construction) and in Madeira and they were also used in India.

McC