TECHNICAL SUPPORT
Published 2026-05-08
Have you ever imagined what would happen if the steering gear suddenly loses its function when a large ship loaded with cargo enters a narrow channel? At that time, I served as the second officer on a bulk carrier of nearly 10,000 tons, and I personally encountered an accident that was almost caused by improper operation. That evening, as the ship was slowly docking, the alarm in the steering gear room suddenly sounded, and the rudder blade was stuck in the left full rudder position. The captain’s yelling with all his strength, the urgent whistle of the tugboat, and the suddenly solidified air on the bridge are still etched in my mind.Later, it was found out that the reason was simply that the operator missed a key link before starting, that is, he did not carry out the steering gear function test in accordance with the regulations.. Since then, I have deeply realized that a set of clear, strict operating procedures that follow the latest standards is not just a decoration on the wall, but the last line of defense for life and property at sea.
The operating procedures of steering gears used on ships are not always the same. Looking back over the past two decades, the international shipping field has revised relevant technical specifications many times. Behind each update almost corresponds to a series of accidents that have actually occurred. In the late 1990s, a ro-ro ship experienced a delay in the response of the steering gear when leaving the port. , had a very serious collision with the dock facilities, causing direct economic losses of more than two million US dollars. After investigation, it was found that the operator was operating in full accordance with the old version of the manual. However, the manual did not cover the requirements for preheating the hydraulic system. In the cold sea, this happened to be an extremely critical and fatal oversight. Therefore, the latest standards clearly add terms on environmental adaptability, emphasizing that before starting, a differentiated preheating process must be carried out based on the oil temperature and external air temperature.
Such a kind of perfection achieved through layer by layer is like an experienced sailor who continues to revise his logbook. At first, it only focused on "whether it can rotate", but now it includes all-round verification of electrical insulation testing, emergency power switching time and full rudder response speed. The operating procedures of modern marine steering gears have established a strict logical chain. Comparing it with the old version, you will find that the new version of the standard is more and more like a "fault prevention dictionary" - it no longer states in a general way "check the steering gear", but is detailed to "under the power loss simulation state, record the duration of switching from the main power supply to the emergency power supply. This value shall not exceed 45 seconds."
Following the latest standards, I break down daily operations into four chronological phases. Each stage is put into the key controllable points extracted from real cases.
The first stage: preparation before launch (2 hours before flight)
Standing in the steering gear room, the first task is not to press the power button, but to carry out a dual inspection operation of "visual and olfactory".
Observe whether the hydraulic oil level is above 2/3 of the scale and whether there is any trace of leakage from the tank breather.
Smell if there is any unusual burnt smell around the motor - this is often a sign of bearing overheating
I once met an old man who always insisted on using an infrared temperature measuring gun to scan each relay terminal block before every startup. As a result, during a routine inspection, he found that the temperature of one terminal block was as high as 87°C, while the ambient temperature at the time was only 28°C. After removing the protective cover, the screws were loose enough that they could be turned with only two fingers. The latest standards make terminal torque checks mandatory quarterly, but smart operators will incorporate it into their daily pre-startup checklist.
Phase 2: Functional testing (in collaboration with the bridge)
In the entire procedure, it is the most easily simplified but the most core link.The correct approach is this: use the local control panel of the steering gear, and then use the bridge remote control system to perform a complete full rudder cycle.. When specifically performing this operation, first the "left full rudder" command is issued from the bridge, and then the operator observes whether the rudder angle indicator and the actual rudder blade angle are synchronized next to the steering gear, and then tests "right full rudder", "positive rudder" and "5° fine adjustment" in sequence. I suggest you use a "two-person review system", that is, one person is responsible for the operation, and the other person holds a stopwatch to record the time it takes for the rudder blade to move from full rudder on one side to full rudder on the other side. According to the latest standards, for electro-hydraulic steering gear, this time should not exceed 28 seconds, and large ships can be relaxed to 30 seconds.
> Keywords: redundant verification
The so-called redundant verification means not to trust a single signal source easily. In the test mentioned above, even if the bridge display shows that the rudder angle is in place, you have to personally confirm whether the mechanical pointer has also returned to zero. On a container ship, the angle sensors of the bridge and steering gear room drifted together, causing the actual left rudder to be 15° but the display screen showed positive rudder. Eventually, the ship deviated from the channel and ran aground. Redundant verification is to use your own eyes to add double protection to electronic signals.
The third stage: running monitoring (recorded every two hours)
When the ship is in normal navigation, the operator's attention tends to shift to other equipment.. However, the newly formulated standards focus on the key point of "active inspections", rather than "passive waiting for alarms". You must create a record sheet covering five core parameters:
The normal value of the current when the pump unit is working is usually printed on the nameplate of the motor. If the deviation exceeds 10%, it is abnormal.
The pressure difference between the front and back of the filter. When the pointer of the meter indicating the pressure difference enters the red area, the spare filter must be switched immediately.
The liquid level fluctuates in the fuel tank. A sudden rise may mean that seawater has entered, while a fall may indicate an external leak.
The temperature of the oil pump housing can be touched briefly with the back of your hand. If it cannot stay for 3 seconds, it has exceeded the 60°C warning line.
Place the screwdriver against the pump housing and put the other end against your ear to listen for the operating noise of the servo. If there is a crisp metal knocking sound, it means the bearing is worn, while a low humming sound is normal.
Stage 4: Emergency Operation and Shutdown
If the steering gear completely fails during navigation, do not blindly start the main pump again and again. The correct approach is: first cut off the main power supply, switch to the emergency power supply, and try to run a single pump. If it still doesn't work, immediately switch to "machineside emergency steering". There is a detail that is often overlooked here: the emergency steering handle must always be inserted into the designated socket next to the steering gear and have a luminous logo attached. In a real case, a crew member spent three minutes in the dark to find the crank handle. The ship was traveling at a speed of 12 knots. Three minutes was equivalent to sailing 1.1 kilometers out of control.
The seemingly small but crucial step in the shutdown process is to manually release the residual pressure in the hydraulic pipeline before turning off the main power supply.. Otherwise, high-pressure oil will remain in the servo valve for a long time, which will accelerate the aging of the sealing ring. The latest standards describe this step as "wait until the rudder blades come to a stop, continue to run the oil pump for 15 seconds and then cut off the power supply." Just these 15 seconds can double the life of the valve group.
Q1: The rudder angle feedback device jumps frequently. Is it necessary to stop sailing for maintenance?
Yes, but you can try to clean the sliding contact of the feedback lever first. If the jump amplitude exceeds 2° and persists, you should stop sailing.。
Q2: How often should the standby pump self-start test be performed?
During the test, it is necessary to simulate the operation of the main pump losing power, instead of directly turning off the circuit breaker. The time is scheduled to be once a month, or before and after each docking.。
Q3: How to deal with excessive foam in hydraulic oil in winter?
To reduce the speed at which the oil temperature rises, start the heater in stages. If the foam is severe, stop the pump immediately and exhaust it.
Q4: What is the allowable deviation range between the bridge remote control and the machineside steering angle?
Within ±1°. Beyond this range, the angle transmitter needs to be calibrated, and it is not allowed to leave the port before calibration.
Q5: How to judge whether the filter is dirty or blocked without relying on the differential pressure gauge?
Listen to the sound the pump makes. Blockage will cause the pump to gasp periodically. At the same time, the motor's current will slowly rise.
Looking through the entire operation process, you can find that the key that the latest standards repeatedly emphasize is not a profound technical principle, but an almost paranoid "confirmation culture", that is, confirming that the oil level is real and effective, confirming that the rudder angle is consistent, and confirming that emergency equipment is within reach. Compared with the version ten years ago, the biggest difference between the old and new standards is that the old standards tell you "what you should do", while the new standards explore "how do you prove that you have done it".
> Keywords: closed-loop thinking
No matter which operation is performed, a closed loop should be formed. For example, suppose you have completed the steering gear test, but this does not mean the end; you need to record the test time, double-sided rudder angle readings, and the operator's name in the engine log. Only when the next person sees the record can he inherit your confirmation result. Closed-loop thinking actually allows every action to retain a traceable chain of evidence, thereby cutting off the possibility of incorrect transmission.
Specific action suggestions are as follows:
Immediately check the release date of the steering gear operating procedures on your ship. If the date is earlier than three years ago, you should apply to the shipowner for an update.
A drill involving all members will be held during this month. The most important thing is to assess "in the event of power loss, switch the emergency power supply within 45 seconds and perform steering."。
Get an A3 size "Six-step card before starting the helm" and paste it at the door of the helm room. The content covers: the position of the oil temperature, the corresponding pressure difference between the filters, the temperature measurement at the terminal block, the test of the intercom on the bridge, the exact identification of the position of the emergency crank, and the exhaust of the hydraulic pipeline.
Before each arrival at the port, use your mobile phone to take a video comparing the actual position of the rudder angle with the image displayed on the bridge, and save it for at least three months.
The safety of ship operation has never depended on the cost of equipment, but on the willingness of each person on duty to strictly follow the standards when no one is supervising. That near-collision experience made me realize: Procedures are not ropes that bind your hands and feet, but beacons that guide you to avoid the reef. From today on, you might as well regard every steering gear operation as a "simulated emergency" - when you are accustomed to treating routines with the most stringent standards, and when a real emergency occurs, your muscle memory will make the right decision for you.
Update Time：2026-05-08
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