Friday, February 4, 2011

THE NAIVE SAILOR , WINCH BRAKE RENDERING-- CAPT AJIT VADAKAYIL


On one of my ships, i received a general circular from the company , that the bow stopper must NOT be put after anchoring, and that ship should put a red flag on the gypsy--so that -- hold your breath-- the wheelhouse OOW can come to know when the windlass brake renders ( SIC!!).

They went on and on in about 18 pages to warn us that if we don't do that, the anchor chain will snap!. And they made a nice video to back their claim. The stupid video had more video graphic content that seamanship content, and it would WOW a retarded 8 year old.   It was amusing to see the anchor cable moving like an anaconda, disregarding the damping effects of seawater and force of gravity.

I wasted no time in being most sarcastic , ( you should never be civil to fools who put sailors lives in danger even if he is related to the almighty queen ) and telling them that the red flag was first introduced to the blue high seas in 1992 by the Russian bunker river operating  barge pretenders who came out to sea with forged certificates.

I declared categorically that i would NOT follow this bullshit (with a capital B ) circular, nor will anybody at sea--and that all the ship staff is already sniggering over this fantastic circular, written by the stupid DPA.

I myself have done thousands of anchorings over 28 years in command with,  100% success rate , on different types of ships , in different locations, in different weather conditions--unlike pilots who are one trick ponies.

Rendering can be tolerated for static braking like the mooring hawser winches--but NEVER EVER for a dynamic high speed gypsy like the anchor windlass.

Imagine a ULCC being held by the windlass brake!

-- what is the principle of the windlass? -- FRICTION right?. You plan to hold a loaded ULCC in an anchorage with swell , with the ship yawing wildly, using friction?

The bow stopper must always be put. First ensure there is NO half twist between the gypsy and the stopper, as is usual.


This rendering thing is the biggest bullshit going on at sea.

On bulk carriers with crane and grabs , which tend to get buried under cargo slides, we test the cranes to proof load . On old ships the brake lining surface and the abutting surface crevice is flushed with carbon remover to get rid of the slippery heat generated graphite layer. Then we tone up the relief valve before the class surveyor comes. The tank is filled with sea water to the required weight . After lifting the proof weight the runner joystick has to be suddenly put to neutral and the crane hook must not creep downwards due to gravity --the automatic brake must grip.  After the test is over we usually tone down the relief valve to the safe working load again. So if the grab gets buried due to a landslide , the relief valve will lift.

Rendering of mooring winches can be done easily ( for the first layer ) with automatic brakes. On manual brakes the torque meter is used on the handle. All this is OK for a split drum which affords only one single layer.

But what about a usual mooring winch drum, where a hawser of 220 metres is wound . It will have minimum 8 layers. When you send the first line ashore or cast off the last line, it will usually be a spring, with 30 metres out on the jetty bollard and the remaining 190 metres in 7 layers on the reel.


Where is the intelligence is doing a brake rendering test on the first layer, for manual brakes once in a year? How relevant is the rendering set point after 365 days?.


It requires a real IDIOT to think, that the brake lining thickness will not reduce, due to wear. Will the the friction coefficient between the metal abutting surface and the brake lining be the same in dry and wet weather?

(These are the same pathetic jokers who wanted NIL vaccum with 100% recirc, or NIL fresh air intake,  for accomodation AC at oil terminals, with the toilet and galley exhaust fans running merrily.)

The forward brake abutting bands on the rotating gypsy is the most under maintained area on the ship. This area can never be painted. On better ships this brake abutting area has a stainless steel veneer. If any salt water ( electrolyte ) enters this crevice it forms a galvanic cell between the brass countersunk bolt heads of the brake lining and the steel gypsy. This galvanically weakens the steel. The surface may look pristine , but it is molecularly weakened. If you chip with a sharp hammer, chunks will break off, like a clay pot. Rendering brings out iron powder .

If the brake renders heat is produced. The heat produces slippery graphite , and it continues slipping.

And nowadays on almost all old ships we find different grades of rope being sent on board --all having the same material on the certificate. But the breaking load will be different. And 60% of this value is what the brake is rendering set point.

Ok you have 4 ropes on the winch reel and the remaining 3 are on the mooring bitt, as a figure of eight . How are we gonna render these ropes on the bitt?. So you give step motherly treatment to 40% ropes--where is the intelligence?

The modern light hawsers do NOT have a friction coefficient ( like the old polypropylene hawsers ) and they slip with a jerk, despite taking two round turns on each bitt and then putting a figure of eight and then again taking full rounds. When hawsers slip with a jerk, they always break. Very rarely can a constant pull break ropes. Anchor chains also break easily when it jerks.

Ever noticed how three tiny Yokohama fenders protect the ship side hulls of two loaded supertankers alongside each other . It is because there is NO sharp bang or surge or jerk or hammer. Remove these fenders and the steel hulls will crumple like paper.

I have taken several deliveries, where the Yard does the first rendering tests. You should see the sheepish look on the face of the man in charge. He knows he has to pull the wool over his own eyes as well as others. Well the ship need this certificate-- without this we will be detained by any inspector.

After you tighten the windlass brake band after anchoring , check how many spare threads are available on the brake handle .

The brass countersunk bolt heads must never come in contact with the gypsy steel. Metal to metal has less friction. And even if it makes contact the brass bolt head will wear off--while a steel bolt can cause havoc. There can be no steel to steel friction , and the steel bolt head will groove the galvanically weakened gypsy abutting surface.

We all play along , and tell the naked emperor--such nice clothes you wear, mE lord!. Nobody has the will to call the bluff.  We deserve to be ruled by fools ashore.

This is why millions our rat guards fell off for the past 300 years and millions will fall off for the next 300 years.

This is why we use the loud hailer cone on the bridge is applied on the mouth for shouting stupid orders. It is actually meant for putting it on your ear and finding out to min 5 deg accuracy, the direction of the foghorn you hear at sea on the bridge wings. In Titanic if the stupid British officers had applied the load hailer to their ears , to find the direction of  lifejacket whistles , instead of their big mouths shouting " Any body there ?" they could have saved more passengers from the freezing water.

Advise:  If you have drums with 8 layers of hawser turns, it is better to make sure you last lines to cast off forward and aft is a rope from the mooring bitts ( especially if the current and the wind can put the ship in trouble ). They never get stuck.


CAPT AJIT VADAKAYIL
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4 comments:

  1. BEAUTIFUL BLOG SIR..KEEP POSTING SUCH BLOGS..THANKS

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  2. You are absolutely right about all above.True seamanship and experiences never get on the desk.
    Thank you sir.

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  3. Beautifully written and simply explained. Keep on writing Captain. hats off to your explanation.

    ReplyDelete