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BLIND SHEAVE

BLIND SHEAVES

WIRE ROPE FALL

FAILURES IN WIRE ROPE

Prepared by Merchant Marine Technical Division Coast Guard Headquarters

GRAVITY DAVIT

FLOATING BLOCK

ACCIDENTS OR EQUIPMENT failures sometimes fall into a pattern of casualties that can teach us lessons in safety engineering. Some recent failures in the wire rope falls of lifeboat davits are in this category.

Unfortunately, in one of these recent casualties, two seamen were in a lifeboat while it was being hoisted from the embarkation deck to the stowage position on the davit trackways. Suddenly one of the wire rope falls parted and dropped one end of the lifeboat and the two seamen into the water. One seaman was injured, and the coroner stated the other's death was by "asphyxia due to drowning."

It seems clear that these men should not have been in the boat during this final hoisting. In the "Manual for Lifeboatmen * * *", Coast Guard publication CG-175, this point is covered in the following, "On boats handled with gravity davits, the boat is hoisted to a position where the tricing lines can be made fast. It is next lowered to the embarkation deck where the men in the boat can get out. It is then hove up to the stowed position, using the hand cranks for the last 12 inches or more. In the stowed position, men can get back in to pass gripes, replace ridgepole and cover, etc."

A Coast Guard investigation followed this casualty. During the questioning, one of the technical witnesses, a marine inspector, stated, "As a rule I have found that falls deteriorate usually in these hidden spots, as we call them, behind blocks and so forth. They are the parts that are exposed to wind and weather and stack gases and so forth." The accompanying photograph shows the failure in this particular wire rope fall.

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6 x 19 wire rope is a nominal designation that can have either fiber or independent wire rope cores and still meet the above regulation. The wire rope manufacturers, however, hold different opinions on the use of fiber cored wire rope as lifeboat falls. One opinion says that the fiber cores become dry and absorb moisture which causes internal corrosion. Such corrosion will not be seen from an outside examination. Another opinion holds that independent wire rope cores are not necessary in the wire rope of lifeboat falls because they are not subjected to high crushing forces on the winch drums. In addition, this faction argues that independent wire rope cores are not justified for the present weights of merchant vessels' lifeboats. The U.S. Navy at present uses hemp-centered wire rope for its lifeboat falls in similar installations. Perhaps in the future the fiber cores will be replaced in manufacturing by a new plastic core made of synthetics, such as polypropylene.

PHOTOGRAPH of wire rope boat fall which parted in service-showing portion of the wire at the point of failure.

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Failures in these wire rope falls occurred at points where the falls were stationary over their davit sheaves. Except for the times during drills, lifeboats on a ship are stowed up on davits with their falls taut and at certain points the falls are in continuous contact with the davit sheaves. These contact points in the wire rope are under pressure from the sheaves and have their lubrication squeezed from the wire strands.

In addition, wire rope falls are exposed to severe atmospheric conditions. Besides frequent baths of salt spray, the davits are often near a ship's stack and receive soot and stack gases that carry sulfur and other acid-making materials. All of this plus the grit from occasional partial bulk cargoes of abrasive materials establish excellent conditions for corroding the wire rope. A few months of this and lifeboat falls can be in a dangerous condition.

Corrosion starts to weaken a wire rope not so much by the loss of metal as by the formation of corrosion pits on the surface of the wires. These corrosion pits are like a number of small nicks and become stress raisers for bending fractures. (One way to break a wire is by nicking and repeatedly bending it.)

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A wire rope is like a machine whose moving parts are wires, strands, and a core. These parts slide and move on each other, wire upon wire and strand upon strand, as the wire rope bends, twists, and straightens. Lubricating this machinery of wire is just as necessary as in any other mechanical equipment. The wire rope must have both inside and outside lubrication at all times to protect its core and to reduce friction, abrasion, and corrosion.

LUBRICATION

When the wire rope is being made in the factory, internal lubrication is provided by lubricating each wire and the core as the wires are laid into strands. This first lubrication is enough to give protection against corrosion during the storage and shipment of the wire rope. Long service life is obtained by frequently lubricating the outside of the wire while in use. This will replace the lubrication normally lost from the squeezing of the rope as it runs over sheaves and drums in various weather conditions.

Crude oil or Bunker C fuel oil should not be used as lubricants for wire rope on shipboard. These oils may contain chemical impurities that might react against the wire rope. The same applies to old greases and crankcase oils from the engineroom which may contain acids or grit.

The best service lubricants for wire rope contain light-bodied compounds with rust inhibitors which have good penetrating properties. These can be dipped, swabbed, or sprayed on the wire rope. The manufacturer's instructions should be carefully followed; some of these lubricants require preheating or thinning with solvent, depending on temperature conditions and vessel operations.

SHIPBOARD MAINTENANCE

On the exposed portions of the wire rope falls, a ship's crew can apply lubrication without lowering the lifeboats. But in spots where the falls are inside of blind sheaves there are places that cannot be reached without lowering the lifeboats and exposing the wire rope. In these places the sheaves are partly covered by steel cheek plates, and a seaman trying to apply oil or slush can't get behind the cheek plates with his brush or swab. Even if the wire rope is clear of a cheek plate, he will not be able to lubricate the side of the wire rope riding tight against

the sheave.

(CHEEK PLATE

CRITICAL SPOT AT "A"

TYPICAL BLIND SHEAVE

CRITICAL SPOT

FLOATING BLOCK

These are the very spots in these wire rope falls that have been failing. The accompanying diagrams show some of these critical spots on different kinds of lifeboat davits.

The correct way to do this job is to lower the lifeboats a few feet so that these critical spots are clear for lubrication. Perhaps the mate will use some markers on the falls so that on lowering he will know when the critical spots are in the clear. This can be done during lifeboat drills when the lifeboats are lowered. These dry portions of the wire rope must have the lubrication thoroughly worked into the strands all around the wire rope before the lifeboat is hoisted and secured again. If this practice is not followed the same 6 to 15 inches of wire rope will stay dry and corrode into a bundle of strands locked together in a solid unit. This interlocking will prevent the sliding action of the wires on each other. Ultimately some of the wires become overloaded and the wire rope fails.

The wire rope fall shown in the photograph failed after 3 years in service. Many steamship companies achieve better service than this by regularly lubricating and turning their wire rope end-for-end. If the wire rope is end-for-ended each year, or at the most every 2 years, the severe corrosion described above is prevented by moving unused portions of the wire to the critical spots. Failures are prevented before they get started.

At the same time the wire rope falls are turned end-for-end the maintenance crews can remove the sheaves from the davits and lubricate the bushings, roller bearings, and sides of each sheave.

THE SAFETY LESSON

Modern wire rope is made to the highest engineering standards. By the use of many tests and controls during its manufacture, it is almost impossible for serious flaws to exist in the finished product. An accident in service with wire rope almost always results from poor maintenance procedures. In the casualties discussed above, the lifeboat davit falls failed because of a continuing lack of lubrication in the wire rope hidden in the blind sheaves.

REGULAR GLASSES OR CONTACT LENSES ARE NO SUBSTITUTE FOR GOGGLES

There are many things worth saving, but nothing is more precious to a man than his eyesight. And, in industry, including the maritime industry, there is probably nothing easier to protect from injury than the eyes.

And yet, there are a number of persons who scorn taking the simple. precautionary measure of wearing safety goggles when there is a possibility of eye injury, little realizing what the consequences might be.

There are others who normally wear regular glasses or contact lenses and consider these as adequate eye protection. Neither, however, are an adequate substitute for safety goggles.

Whether you wear regular glasses, contact lenses, or no glasses, you can be sure of giving your eyes the best protection if you wear safety goggles when engaged in such tasks as scaling, chipping, wire brushing, sweeping or shoveling dirt, or washing or scrubbing overhead with strong solutions.

Would you wear a bathing suit when shoveling snow?

Not such a bright idea, is it? It's always a good idea to dress right for the job you're doing, says the National Safety Council.

That means wearing the garments of safety-hardhat, gloves, goggles. safety shoes—when the job calls for them.

Going without proper protective clothing, even for a few seconds, is like walking barefoot through the

snow.

And the results can be far more disastrous.

"Give me a lever and a place to stand, and I'll move the world," said a Greek philosopher.

You probably won't be called on to move the world, but you can learn to lift and move heavy objects safely and easily.

Some tips from the National Safety Council:

1. Don't be a hero. Get help with large, especially heavy objects.

2. Set your feet solidly, slightly apart, and crouch low over the object.

3. Get a firm grip, hands on diagonal corners. Lift one end if necessary to get a hand under the object. 4. Keep your back straight, bend at the hips. Straighten legs slowly, letting the leg muscles, not the back, I do the work.

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There were 921 vessels of 1,000 gross tons and over in the active oceangoing U.S. merchant fleet on May 1, 1963, 10 less than the number active on April 1, 1963, according to the Maritime Administration. There

were 19 government-owned and 902 privately owned ships in active service. These figures did not include privately owned vessels temporarily inactive, or government-owned vessels employed in loading storage grain. They also exclude 23 vessels in the custody of the Departments of Defense, State, and Interior, and the Panama Canal Company. There was a decrease of 9 active vessels and an increase of 10 inactive vessels in the privately owned fleet. Two freighters, American Chieftain and American Commander, were delivered from construction. One freighter, the Halcyon Pioneer, was turned in to the Government as an exchange ship.

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The Panama Canal began roundthe-clock operations recently. This was a result of a decision by the Panama Canal Company to place the locks at the Pacific entrance on a 24-hour basis.

The Miraflores and Pedro Miguel locks have been operating 17 and 19 hours a day, respectively. The Atlantic locks have been operating on a 24hour basis for seven years.

Ships arriving at either entrance will be started through the canal as soon after their arrival as they can be accommodated in the day's transit schedule.

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CAPTAIN LUTHER A YOUNGS, Saint Lawrence River Pilot, is shown receiving a Letter of Commendation from the Commandant at Cape Vincent, New York. LCDR W. F. Raes, OCMI, Oswego, N.Y. in conjunction with the crew of the Coast Guard Cutter White Lupine, made the presentation on behalf of the Commandant. The Letter of Commendation was presented to Captain Youngs for his part in the safe escort of the tug Russell 20 from near Rochester to Cape Vincent during a northeast gale.

Captain Youngs was serving as Pilot on the Norwegian tanker Bratsberg at the time of the incident. The letter read in part "Although the Bratsberg was unable to take the tug in tow, the vessel, under your skillful handling, provided a lea and safely escorted the tug into Cape Vincent, New York. As a result of your skillful seamanship, valuable property and life were saved. As Commandant of the Coast Guard, the principal agency of the United States entrusted with safety of life and property at sea, I am pleased to commend you for your outstanding courage, vigilance, and performance of duty, which should afford you a great measure of personal satisfaction and is deserving of the highest praise."

Farrell Line's cargoliner African Neptune set a new speed record on her maiden voyage to Capetown, South Africa, the marine press reports. The new mark, 12 days 13 hours 36 minutes, was an improvement over the maiden-voyage record set by her sister ship, the African Comet, during 1962.

Two new cargoliners of the Delta Steamship Lines have set speed records during the month of March: the Del Sol averaged 18.53 knots for 6,347 miles between Galveston and Buenos Aires, while the Del Oro completed a 5,326-mile voyage from Rio de Janeiro to Houston in 10 days 22 hours, for an average of 20.3 knots.

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Marine Board of Investigation; collision between SS Olympic Rock, Liberian flag, and the tug Princess with the tank barge W. L. Graham in tow in the Delaware River on 21 February 1962 with loss of life

The record of the Marine Board of Investigation convened to investigate subiect casualty, together with its Findings of Fact. Conclusions and Recommendations has been reviewed.

On the morning of 21 February 1962, during periods of low visibility, the Liberian tanker Olympic Rock, bound for Puerto La Cruz. Venezuela, in ballast, was proceeding down the Delaware River under the direction and control of a pilot, having discharged her cargo at Philadelphia. All navigational equipment was in good operating order with the exception of the course recorder. The radar was being operated by the master on the 2, 4, and 8 mile scales. The vessel's speed was changed from time to time to allow for variable visibility limitations and traffic conditions. A lookout was posted on the bow and, except for a speed reduction while passing an upbound vessel, the voyage was without incident until the vessel reached the northern section of Bellevue Range. At this time two targets were observed ahead on radar at a distance of approximately 2 miles and in a position which was estimated to be approximately at the junction of Bellevue and Cherry Island Ranges. Shortly thereafter these targets were visually sighted at an estimated range, of slightly over 1 mile. They were identified as two upbound tugs with tows one of which was dead ahead and the other slightly off the port bow. The vessels ahead were later identified as the tug Princess with the barge W. L. Graham in tow, and the others, off the port bow. as the tug B. M. Thomas with three barges in tow. The pilot of the Olympic Rock, then proceeding at an estimated speed of 7 knots over the ground against a flood current of approximately one and one-half knots ordered speed reduced to slow ahead, sounded a single blast on the whistle and simultaneously executed a slight course alteration to starboard. The Princess, with its tow made fast to her starboard side, appeared to be in a position close to the center of the dredged channel and on a collision course. Receiving no response to the first whistle signal and having observed no course change by the Princess, the Olympic Rock sounded a second single blast and again altered course to starboard. Shortly thereafter, observing what appeared to be a course alteration to port by the Princess, and having received no answer to the second whistle signal, the Olympic Rock again sounded a single blast and altered course again to starboard. Receiving no response to this third signal, the pilot of the Olympic Rock sounded the danger signal and ordered the engines full astern. At 1041, approximately 3 minutes following the initial whistle signal of the Olympic Rock, the two vessels collided in a position nearby Buoy 1B located in Bellevue Range on the western edge of the dredged channel. Physical contact was made between the stem of the Olympic Rock and the port side of the Princess at an angle of approximately 30 to 40 degrees between centerlines of the two vessels. The shock of impact parted the tow lines to the barge W. L. Graham setting her adrift, while the Princess heeled to starboard rolling under the

bow of the Olympic Rock and shortly thereafter surfaced off the Olympic Rock's starboard bow. Upon surfacing the Princess capsized, disappeared beneath the surface and came to rest on the bottom with its mast remaining visible above water. Upon sighting one survivor from the Princess aboard a life float and two others in the water in close proximity to the capsized tug, crewmen of the Olympic Rock tossed life rings overboard and made preparations for launching a boat. Shortly thereafter a Corps of Engineers motor vessel arrived on the scene to assist while the Olumpic Rock was maneuvered to Cherry Island Flats where she anchored and stood by to render such additional assistance as might be needed.

The

On the morning of 21 February 1962, the tug Princess with the light tank barge W. L. Graham in tow on the starboard side departed an area just north of Federal Anchorage No. 5 in the vicinity of New Castle Range, Delaware River, bound for Chester. Pennsylvania. Princess, manned by a crew of four, was encountering intermittent snow flurries with resultant limited visibility and, when in a position on the right hand side of Deepwater Point Range, in the vicinity of Penns Beach, the operator considered anchoring until visibility improved. Although the operator ordered a deckhand to proceed to the bow of the barge to stand lookout watch, visibility conditions improved before he had manned his station and he was subsequently ordered below. The Princess. with wheelhouse doors and windows closed, continued on its voyage, navigating the right hand side of the dredged channel. The tug B. M. Thomas with three barges in tow astern entered the Delaware River from Christina River and fell in astern of the Princess. Upon reaching a position approximately abeam of Buoy 4C, Cherry Island Range, the operator of the Princess observed a buoy tender approximately 1 mile distant upriver and close aboard Bellevue Range Lighted Buoy 2B. Shortly thereafter the operator of the Princess altered course slightly to left to cross to the left side of Bellevue Range, ostensibly to give the buoy tender a wide berth since that vessel was displaying the prescribed signal for a Coast Guard vessel engaged in servicing an aid to navigation. The operator of the Princess related that he proceeded to the western extremity of the dredged channel, passed the dredge Comber, moored to the Corps of Engineers' installation, at a distance of 20 to 50 yards and thereafter left the black channel Buoy 1C on his starboard side. Further, that upon sighting the downbound vessel ahead, later identified as the Olympic Rock, the Princess was actually beyond the western extremity of the dredged channel, that no attempt was made to alter course to starboard until immediately preceding impact, and that the collision actually occurred outside the dredged channel. However, the preponderance of evidence clearly demonstrates that, when first within sight of one another, both vessels were in an approximate mid-channel position with the upbound tug on a course as to allow for gradual passage to the western edge of the dredged channel. The Olympic

Rock, upon sighting the tug in a mid-channel position, altered to starboard for a normal port to port passage. While the course of the tug was not readily apparent, it was reasonable to assume that, in response to the Olympic Rock's single blast on the whistle, the tug would so maneuver as to comply with the narrow channel rule. Instead, the operator of the Princess failed to hear any of the three single blasts sounded by the Olympic Rock and, except for a slight alteration further to the left in an effort to reach the western extremity of the channel more rapidly, he failed to exercise any further evasive maneuvers until the two vessels were in extremis. As the Princess approached a position immediately upstream from Buoy 1C, the range of the two vessels had closed to approximately 75 yards. Upon closing to about 20 yards, the operator of the Princess sounded one blast on his whistle and attempted to maneuver to the right with hard right rudder. Upon impact the Princess heeled to starboard and went under and when the operator surface he found himself on the starboard side of the Olympic Rock and managed to swim to a life raft from the Princess which he observed floating nearby. As the Princess momentarily surfaced, three other crewmembers were observed, but they subsequently disappeared after entering the water.

As the result of the casualty three lives were lost, the Olympic Rock suffered structural damage to its bow section, the barge W. L. Graham sustained plate and internal damage and the Princess, though subsequently salvaged, suffered extensive hull and machinery damage.

REMARKS

Concurring with the Board, it is considered that the Princess failed to comply with Article 25, Inland Rules (33 U.S.C. 210) which provides "In narrow channels every steam vessel shall, when it is safe and practicable, keep to that side of the fairway or mid-channel which lies on the starboard side of such vessel." More specifically, it is clearly evidence that the chain of events which led to this collision first began when the operator of the Princess elected to proceed to the left hand side of the channel. The subsequent failure to alter course to starboard upon first sighting the Olympic Rock in a meeting situation merely aggravated what was already a potentially hazardous condition. The presence of the buoy tender is considered insufficient justification for having departed from established rules, particularly since the evidence indicates the B. M. Thomas effected a successful passage without incident.

Notwithstanding an unobstructed view from the pilothouse of the Princess, the operator's failure to hear the

whistle signals of the Olympic Rock constitutes evidence of a failure to provide a proper lookout. Numerous Court decisions support the contention that a proper lookout must include audio as well as visual capabilities. While largely conjecture, it is reasonable to suppose that, had a lookout been posted as far forward as possible, the intention of the Olympic Rock would have been known to the Princess in sufficient time as to avert a casualty. A further contributory factor was the failure of the Princess to render a whistle signal of intent upon first sighting the oncoming vessel.

The Board's conclusion that the Olympic Rock failed to comply with the provisions of Article 18, Rule III, Inland Rules (33 U.S.C. 203), is concurred in. The evidence clearly demonstrates the doubt being experienced by the pilot of the Olympic Rock as to the intent of the Princess when, on three successive occasions, he sounded a one blast signal and altered course to starboard without receiving a response. The above rule specifically provides that "if, when steam vessels are approaching each other, either vessel fails to understand the course or intention of the other, from any cause, the vessel so in doubt shall immediately signify the same by giving several short and rapid blasts, not less than four, of the steam whistle".

Consistent with the recommendations of the Board, a copy of the Board report together with a copy of this action will be forwarded to the American Pilot's Association for referral to the cognizant State Pilot Authority and appropriate action concerning the performance of duty of the pilot of the Olympic Rock while acting under the authority of his State Pilot's license.

It is considered that the primary cause of this casualty was the failure of the tug Princess to comply with Article 25, Inland Rules (33 U.S.C. 210), and, since loss of life resulted, this failure constitutes evidence of criminal negligence.

The Board's recommendation that appropriate action under the administrative penalty procedure be initiated against the owners of the Olympic Rock is not concurred in. 33 U.S.C. 159 provides for a penalty against a vessel for failure to comply with Inland Rules of the Road. However, from the evidence it would appear that, in this instance, the responsibility for any navigational faults of the Olympic Rock must rest entirely upon the officer under whose direction and control the vessel was being navigated.

Where not in conflict to the foregoing summary and remarks, the record of the Marine Board of Investigation is approved. E. J. ROLAND, Admiral, U.S. Coast Guard, Commandant.

EXERCISE EXTREME CARE WHEN IN THE VICINITY OF A MOVING LIFT TRUCK

Recently at a major seaport pier both legs of a longshoreman were broken by a heavy case which toppled over while being transported on the blades of a forklift truck.

Seamen and longshoremen do not always realize that loads being carried on forklift trucks plus momentary inattention can cause serious injury or death. Also, the blades on these

trucks are very sharp and are some-
times carried at heights that will
inflict serious bodily injury on the
unwary even though they are not
carrying any load. Persons in the
area of moving lift trucks must keep
a weather eye out for trouble and keep
a safe distance away. These trucks
have a tendency to swerve out of con-
trol when the wheels are blocked or

impeded by obstructions on the pier surface.

One should use extra care when passing through pier areas where the trucks are operating and where sunlight is blocked off by large vessels docked on both sides of the pier. A voyage is not ended until safe arrival at home with your loved ones.

Courtesy G. Tranchina

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