A Thermal Balancing Act 

Keep your engine at the right temperature. 

Midsummer is here and your main and generator engines are getting a workout. With surrounding water temperatures in Galveston Bay reaching the mid 80°'s, they will soon post above 90°F within a few weeks. To run a diesel, excess heat has to be dissipated. A modern diesel engine operates with a thermal efficiency around 35%. This means that the remaining percentage of heat must be transferred away from the engine.

  

The excess heat that is developed through combustion and friction in the engines is transferred primarily away through two mediums, the exhaust and the engine coolant. Up the stacks goes the exhaust; the rest we must deal with using a cooling medium through the cooling circuit.

 

This process is part of the thermal balance of the engine.

Chevron Delo

 

Cooling Medium

 

On Higman boats, water is mixed with a combined "Supplemental Coolant Additive (SCA) and Antifreeze" which protects the cooling circuit parts from wear and also increases the range of the boiling and freezing points.

  

Typically used on Higman Vessels is Chevron Delo Extended Life Coolant/Antifreeze or Fleetguard #CC 2820. Both require a 50/50 mixture with water. It is important to keep the correct mixture percentage to keep the Freezing/Boiling extremes just beyond the operating temperature range of the engine.  For example:

 

Coolant /Water Ratio	Freeze Point	Boiling Point
50/50	-34°F	+265°F
60/40	-62°F	+270°F
40/60	-12°F	+224°F

  

The 50/50 percent range is well within the operating parameters of our engines, thus makes most sense.

 

Engine and Generator coolant should be checked as part of your weekly inspection.

 

To do a proper engine coolant test go to Boat Engine Coolant Test Strips for details.

 

Keel cooler

The coolant medium transports the excess heat absorbed form the cooling circuit to the keel coolers. A keel cooler is a closed circuit cooling unit mounted on a vessel's hull beneath the waterline. Heat is dissipated to the surrounding water.

 

Higman vessels are equipped with three keel coolers per side; main engine, after cooler and generator cooler. Each is specifically sized to transfer enough heat from the connected engine to keep the heat transfer in balance. Keel coolers are made from a 90/10 alloy of copper and nickel. The alloy along with the units operating temperature will tend to keep the exterior of the unit free of marine growth.

 

Fernstrum Keel Cooler Application

Overheating

Overheating of an engine is a serious problem. A temperature of 180°F to 190°F should be considered normal. If the engine coolant temperature gradually increases;

• Check coolant level, is the coolant within specifications? Look for leaks, and test coolant.
• Keel cooler;  Is there enough water flow around it? When working in shallow water, check to see if mud has blocked the keel cooler channels? Is there a buildup of marine growth (oysters) inside the keel cooler external box that may block water flow through the cooler channels?
• Keel cooler connecting hoses; Has a wire reinforced jumper hose collapsed, blocking flow?
• Engine lube oil levels; Are lube levels above or below specified levels?
• Coolant temperature gauge; Is the gauge malfunctioning?

Other possibilities:

• Has the keel cooler been damaged or crushed in a allision/collision?

• Could anything have gotten into the cooler nozzles? Corrosion build up and foreign particle could cause a blockage inside the cooler?  Flush cooler.

• Oil in the cooler;  Has an engine problem caused oil to build up inside the cooler, insulating heat transfer?

The Spark of Static

Let the static dissipate!

As cargoes fill a tank, static electricity can accumulate within the cargo. This static electricity is created when electrons from one atom are transferred to another atom upon contact. This is most apparent during the beginning of a transfer when your cargo hits the bottom of the tank. For this reason, we start our transfers at a slow rate. However, some cargoes will continue to accumulate static throughout the transfer when the cargo entering the tank makes contact with the cargo already in the tank.

So why is static dangerous? Static Electricity will remain until one of two things happen. The first is a gradual bleed off through ground. The second, more dangerous, is a quick neutralization by discharge. This discharge can be seen when you are at home in your slippers. As you shuffle your slippers across the carpet you accumulate static electricity. Then when you reach for the door you see a small spark and a sharp ting in your fingers. This little spark can cause ignition of your cargo!

At Higman our policy that states:

"During the cargo transfer and for 30 minutes after completing the loading - ullage and sampling equipment must not be put into the tank."

This 30 minute period allows the static to slowly bleed off and prevent the sudden discharge of static. NO SPARK!

As Captain/Relief Captain of a vessel you are responsible for the safety of the vessels and crew. As PIC of a barge you are responsible for the safe transfer. Boat Captain and PIC should ensure that this policy is followed.

We would like to commend the crew of the M/V POTOMAC for their due diligence in preventing a possible static event during a recent cargo transfer.

While at a dock, a cargo inspector attempted to gauge one of their barge tanks while the crew was still topping off. Being on top of the operation, the POTOMAC's crew observed the cargo inspector and stopped him from a potentially dangerous act. 

If you should experience this situation please stop the inspector and call dispatch to report the issue.  

Tankerman Alfred Hernandez and Captain Bobby Espinosa off the M/V POTOMAC

2012 Devlin Awards

The Jones F. Devlin Awards, sponsored by the Chamber of Shipping of America went this year to 41 Higman boats with a total of 260 years of injury free operation!

Jones F. Devlin Awards are awarded to all self-propelled merchant vessels that have operated for two full years or more without a crewmember losing a full turn at watch because of an occupational injury. This year's awards go to:

M/V ABERDEEN - 12 year certificate

M/V ALLIANCE - 3 year certificate

M/V ANNAPOLIS - 11 year certificate

M/V ANTIETAM - 9 year certificate

M/V ARUNDEL - 12 year certificate

M/V BALTIMORE - 12 year certificate

M/V BETHESDA - 6 year certificate

M/V BOLIVAR POINT - 5 year certificate

M/V CAPT. JACK HIGMAN - 4 year certificate

M/V CECIL - 9 year certificate

M/V CHESAPEAKE - 12 year certificate

M/V COVE POINT - 6 year certificate

M/V CUMBERLAND - 10 year certificate

M/V DECATUR - 7 year certificate

M/V DRUM POINT - 6 year certificate

M/V ERIK SALEN - 2 year certificate

M/V FREEPORT - 5 year certificate

M/V GEORGE H. THOMAS - 4 year certificate

M/V GREBE - 3 year certificate

M/V GRETCHEN T. - 4 year certificate

M/V JESSE B. GUNSTREAM - 3 year certificate

M/V JOHN T. MCMAHAN - 3 year certificate

M/V KYLE A. SHAW - 2 year certificate

M/V LAVACA BAY - 2 year certificate

M/V LOUISIANAN - 5 year certificate

M/V MARK E. FLYNN - 3 year certificate

M/V MARRERO - 13 year certificate

M/V MATAGORDA - 4 year certificate

M/V MISS CYNTHIA - 10 year certificate

M/V MISS MARIANNE - 7 year certificate

M/V MISS SARAH - 2 year certificate

M/V PELICAN - 7 year certificate

M/V PIMLICO - 6 year certificate

M/V POINT ISABEL - 4 year certificate

M/V PRESTON N. SHUFORD - 3 year certificate

M/V ROCKFISH - 5 year certificate

M/V SABINE PASS - 4 year certificate

M/V SANDY POINT - 7 year certificate

M/V SEVERN - 9 year certificate

M/V SKIPJACK - 8 year certificate

M/V TEXIAN - 11 year certificate 

3rd Quarter CBT

Third Quarter CBT courses will be available on Wednesday July 18, 2012. This quarter's courses will include:

• Confined Spaces
• Onboard Firefighting Systems
• Safe Use of Deck Winches
• Higman Health and Safety Policy

Please encourage all crew members to complete their training early.

We are also pleased to announce our 2000th CBT Certificate Award winner is Gregory Bullock, tankerman on the M/V Severn. Mr. Bullock won a $150 gift certificate for Walmart.

Stern Shots

A joint man overboard drill was held last week aboard  the M/V BALTIMORE, M/V DRUM POINT and M/V SAN BERNARD

Sunrise on the Cumberland River approaching Barkley Lock D/B. Pilot Ben Carpenter

Deckhand Jason Evans takes his first flight.  Capt. Mike Maneely keeps him in line!

Nautical Trivia  

Explosions on the Waterways.....Steamboat boilers in the mid-1800's. 

The early days of steamboat travel on the Rivers and Intracoastal Waterway were hazardous in many ways. Vessels routinely sank, caught fire and had collisions. In just the first 40 years following the introduction of the steamboat by Robert Fulton in 1807, it is estimated that approximately 500 steamboats were lost to accidents with a death toll of nearly 4,000 people. So frequent were the steamboat accidents and sinking's that the average lifespan of a steamboat was only four to five years.

One of the greatest causes of steamboat casualties was boiler explosions. With boiler technology in the infant stages, there was still a long way to go in understanding the construction, maintenance and operation of high pressure boilers that provided steam to run the boat's engines. Explosions were so frequent, that Charles Dickens compared traveling aboard a high-pressure steamboat with living "on the first floor of a gun powder mill."

The mid 1800's steamboat boiler was hardly more than a large tea kettle filled to a certain level with water. A fire box surrounding the kettle was loaded with wood or coal, providing heat to convert the water inside the boiler to steam. The steam is then piped to a reciprocating piston engine to drive the paddlewheel or in later times, the propeller. As the liquid water is converted to stream, make-up water has to be continually added to the boiler.

The pressure instruments used the boiler were simple and not at all accurate. A steamboat engineer in those times used his senses, especially hearing, to monitor the water level in the boiler. Let most of the water boil out of the boiler and the chance of an explosion increased greatly.  

Steam engine and boilers from the S/V ARABIA which sank in 1856.

In the case of steamboats, boilers naturally were placed down within the infrastructure of the boat. Explosions therefore had a catastrophic effect occurring deep inside a wooden vessel. Steamboats would literally blow apart in a ball of fire and hot steam. In many cases, those who did not die during the explosion itself, often drowned after jumping or being thrown into the water. 

Galveston Daily News, Jul 18, 1873