Archive | Hydraulics

Bringing New Life Back to an Older 112’ Westport Yacht

We are seeing a growing number of new owners of older 112’ Westports. This “Made in America” production boat has a lot to offer but many of these vessels are purchased without a solid maintenance history. Nevertheless, their new owners/Captains still want to bring them back to life.  In order to do that, sometimes a total refit of the vessel is required.

One of these new owner refits spent a few months at LMC getting a full paint job, mechanical upgrades, interior work and hydraulic systems overhaul and refurbishing. Our capable team of hydraulic technicians was tapped to handle all the hydraulic projects.

Starting with the Naiad stabilizer system, we did a full rebuild including removing the shafts and bearings.  The entire stabilizer actuator system was also rebuilt back to new.  The stabilizer shaft had some corrosion in the lip seal area from sitting too long in salt water so our on-site machine shop, Straight Line Marine, performed a cladding repair.

We then moved on to work on the entire hydraulic central system where we performed a full hydraulic fluid flush, cleaned and pressure tested the heat exchangers and changed all the filters.

In the engine room, we found that we needed to change a large number of the hydraulic hoses.  Hydraulic hoses have a 10-year life and can cause huge problems when they fail on the high-pressure side so it is very important to inspect and replace them during routine service.

We also did a little work on the bow thruster, installing new seals in the lower leg, adding fresh gear oil and testing the hydraulic motor.

Stainless steel ring on main gear

Our team did a full rebuild on the single Maxwell 4500 windlass on the bow, down to the gear box including installing new seals and bearings.  As part of the rebuild, Straight Line Marine also fabricated new stainless steel rings for the main gears to help prevent future gear oil leaks around the lip seals. We also replaced the small Maxwell 2500 capstans in the stern with new electric units due to the cost of installing new versus re-building these smaller units.

We found the steering system to be in good shape.  There were no leaks on the cylinders so these were left alone.  We did, however, replaced a few hoses and upgraded some of the ball valves to stainless steel to help prevent future corrosion.  Finally, we changed the fluid and filters.

This was a big job from start to finish but our talented hydraulic technicians, supported by our in-house machine shop, were more than capable of tackling every hydraulic system from bow to stern and everything in between.

Repair, Service and Maintenance for Vosper Stabilizers

It is not uncommon to find Vosper stabilizers in many older yachts and ships. What is uncommon these days is to find a company that specializes in the repair, service and maintenance of the older units. VT Motion, the company that supplied Vosper stabilizers, was acquired by Naiad in 2009 and absorbed into its Naiad Maritime Group.

Increasingly, we hear from many ship’s captains and owners that when they seek to maintain their Vosper stabilizers, they are often urged or even forced to upgrade and replace these stabilizers with newer models. It seems that the major stabilizer companies are shying away from Vosper in lieu of recommending a major upgrade – an upgrade that can be expensive and time consuming.

At High Seas Hydraulics, we specialize in the repair, service and maintenance of all types of stabilizer systems including Vosper, Naiad, Quantum and others. If you are looking for expert hydraulic technicians to work on your stabilizer systems, whether older models like Vosper or newer ones on the market today, look no further than High Seas Hydraulics.

 

Rebuilding instead of Replacing a PTO Pump Can Translate into Big Savings for a Vessel

Our Hydraulics team was recently called upon to work on a PTO (power take-off) pump that was driven off the vessel’s main engine transmissions.

Removal of the pump was extremely difficult due to corrosion between the pump shaft splines and the coupling.  The corrosion was due to exposure to saltwater and normal wear and tear. In the marine business, the internal and external splines that make up the coupling usually reside on different pieces of equipment supplied by different vendors. The SAE Involute spline standards are the most commonly used for shaft diameters between ½” and 2”. The tolerances are loose enough to insure multi-vendor interchangeability while still providing torque transmission significantly higher than a keyed coupling. The tight fit avoids any lash and excessive wear in the splines over the life of the pump. There are many benefits in using spline shafts in place of a keyed shaft for this application. The spline connection offers a load distribution which is equal along the teeth sides enabling both to rotate together. Consequently, this load produces a longer fatigue life compared to the keyway drive.

In this case, the corrosion had damaged the spline surfaces and locked the two parts together. What would normally take a couple of hours, ended up taking almost two days to complete. Once finally removed, it was apparent that splines were damaged beyond repair.  The only solution was rebuilding the pump with a new shaft and the correct size splines.  Splines come in many different sizes and types, so replacement must be an exact match.

Once the pump was rebuilt, we re-assembled with the main engine transmission and installed it back in the boat. By rebuilding the pump, we saved the captain thousands of dollars.

Need Running Gear and Hydraulic Work Done on your Yacht – Work with Us

A 106’ Westport yacht was recently hauled at Lauderdale Marine Center for a variety routine maintenance projects including shaft work, bearing replacements and an overhaul on several hydraulic systems. To streamline the process and help the captain and crew better manage the project, they contracted with both High Seas Yacht Service for the running gear portion and High Seas Hydraulics to handle the hydraulics work.

Our running gear mechanics inspected the shafts to ensure they were straight and aligned and replaced the bearings and seals. Normal wear and tear associated with running the vessel and prolonged exposure to salt water makes this task a necessary evil for properly maintaining the boat. As seen in the adjacent photo, there was a visible gap where the cutlass bearing adjoined to the shaft.

We were also commissioned to replace the seals on the lower stabilizer fins. ABT Trac, one of the more popular brands, recommends changing the lower stabilizer fin seals every couple of years but at least every six years depending on use. The components on the stabilizer are constantly working except is absolute calm seas, so the wear and tear can be considerable. After dropping the fins, we proceeded to change out the old lower stabilizer fin seals with new ones, check the hoses and cylinders, then reassembling the units.

In addition to the routine maintenance on the stabilizer systems, we flushed the entire hydraulic system using the simple drain, filter, fill approach commonly referred to in our shop as a DFF. This type of flush is more of an “oil change” and is part of routine maintenance. It is not appropriate where a more serious condition such as water, metal particles or other contaminants are found in the oil. The process calls for draining the hydraulic tank, changing out the filters and refilling the tank with hydraulic fluid.

To round out the work on this Westport, we did an overhaul on the bow thruster, single Maxwell windlass, the boat’s heat exchangers and the hydraulic steering system which was slow to respond.

From running gear to hydraulics, our teams at High Seas Yacht Service and High Seas Hydraulics, make easy work of maintaining the systems that make your vessel safe and operating smoothly.

Refurbishing Hydraulics Parts for a 118-foot Yacht

When a 118-foot yacht was hauled out at Lauderdale Marine Center for a full refit including paint, our hydraulics team was called upon to refurbish some of the vessels hydraulic parts including its deck crane and side boarding ladders. After a thorough inspection, we removed the units and rebuilt them to “like new condition.” We stripped the units for paint and replaced all hydraulic hoses, cylinders and hardware. Once the other work is completed on the yacht, we will re-install the side boarding ladders and crane. The “new” side boarding ladders and deck crane will complement the look of the refitted vessel and provide years of service for future voyages.

Hydraulic Flush – When, Why and How

Every system on a mega yacht is important to the overall comfort and safety of the vessel and vessel’s using hydraulics are no exception. So how often should a hydraulic system, like those used for the steering, stabilizers, bow thrusters or windlass operations be flushed? To be on the safe side, a sample of the hydraulic fluids should be tested every six to 12 months or whenever the system is opened and potentially exposed to outside contaminants, you suspect that water may have infiltrated the tank or metal particles are found in the oil.

There are three methods for flushing a hydraulic system. The first is a simple drain, filter, fill approach referred to in our shop as a DFF. This type of flush is actual more of an “oil change” and is typically recommended for routine maintenance.  It is not appropriate where a more serious condition such as water, metal particles or other contaminants are found in the oil. In this scenario, we would drain the hydraulic tank, change out the filters and refill the tank with hydraulic fluid. Pretty straight forward.

The second method, known as a double oil and filter change, requires us to drain the hydraulic tank and fill with fresh oil that will be circulated using on-board system pumps. This method would be suggested under a few conditions; many years since last oil change, requirement to change oil types, minor discoloration of oil, etc.  This method involves an initial oil drain from the tank and low points in the system and filter change which can expel a large percentage of contaminants and degraded fluid. We would then fill the tank to the minimum level allowable to still safely work and circulate the oil until operating temperature is achieved. The oil is drained again and the filters changed for a second time before re-filling the hydraulic tank with fluid. For best results, the system should be drained as thoroughly as possible including the tank and manually cleaned.

The last option is more time consuming and costly and is used when there is known contamination of water or metal particles. This method often uses special high pressure pumps or power flushing rigs. Some of these pumps or rigs have directional valves that enable flushing direction to be changed which can assist in dislodging contaminants from dead spaces throughout the system. As in previous methods, the first step is to drain all old hydraulic fluid from the system and refill with a low viscosity fluid that will be circulated at high velocities to create turbulent flow conditions that equate to a Reynolds number of more than 2,000. This process would be repeated as needed until there is no longer any contaminants present in the filters or fluid. We would also remove, inspect and when necessary replace any hoses, cylinders and valves that are damaged.

Just like changing the oil in your car or any other mechanical device, hydraulic systems on your yacht need care and attention to keep them performing in peak conditions for years to come.

Repairing a leaking Heat Exchanger in a Bow Thruster HPU

We were recently contracted to inspect a leaking heat exchanger on a 130 foot Westport yacht docked at a local marina. The heat exchanger was part of the hydraulic power unit (HPU) for the ship’s bow thruster system.  The HPU consists mainly of a motor, a reservoir tank and a hydraulic pump. These units can generate a tremendous amount of power to drive most any kind of hydraulic ram or motor. They can also generate high temperatures. Most heat exchangers used in the marine industry are water cooled and use a water control valve to regulate the flow of water though the exchanger to keep the hydraulic fluid temperature between 64 and 68 degrees C (147 and 155 degrees F). It is important to make sure the adjustments for the water control valve are set properly to avoid rapid overheating.

This particular model was a shell and tube design.  As its name implies, this type of heat exchanger consists of a shell (a large pressure vessel) with a bundle of tubes inside it. One fluid runs through the tubes, in this case hydraulic oil, and another fluid, water, flows over the tubes (through the shell) to transfer heat between the two fluids. The set of tubes is called a tube bundle and may be composed of several types of tubes.

Upon inspection, we found that the fittings in the heat exchanger were not properly seated and the sealant used was not sufficient for the job. In order to remedy the problem, we needed to remove the heat exchanger from the HPU and send it out for servicing. In order to do this, we had to disconnect the hard pipe Stauff clamps above the heat exchanger in order to spread the pipes apart to remove the heat exchanger from the bilge. We also disconnected and installed caps and plugs in the hoses connected to the heat exchanger. We resealed the adapters and fitting upon re-installation, connected the hydraulic hoses, installed Stauff clamp supports and tested the unit for leaks.

The heat exchanger is back in operation and helping to ensure that the hydraulic bow thrusters are doing their job helping to maneuver this yacht in tight places.

 

Overhauling BCS trim tabs on an 85 foot Ferretti

BCS Trim Tab

Trim tabs are an essential component for any yacht. They improve performance, helping to increase speed, reduce pounding and on smaller boats offset prop torque. They help the vessel run more efficiently, reducing fuel consumption and engine laboring and eliminate “squatting.” But more importantly, they increase safety by improving visibility and handling along with reducing wake size and hull stress.

However, years of use and prolonged exposure to salt water can take a toll on their ability to function properly as was the case with an 85’ Ferretti that was hauled at Lauderdale Marine Center.

That is when our hydraulics team was called in to work on the BCS hydraulic trim tabs. Upon close inspection, we found that two of the four trim tab cylinders were corroded beyond repair and needed to be replaced. Because of manufacturer’s long lead time, we decided that we would machine new rods, barrels and re-build the cylinders in-house, using our machine shop, Straight Line Marine.

Corrosion in Barrel

The corrosion we found on the inside of the barrel was caused by salt water intrusion as a result of failed seals. Once the components were machined, we were ready to assemble the new hydraulic trim tab cylinders and re-install in the yacht. Unlike common trim tab cylinders, the BCS model does not use hydraulic hoses to distribute the hydraulic fluid to operate the trim tabs. The fluid is dispersed through a small pin hole in the transom bracket assembly. A clever design that eliminates hose failure external to the transom. However this creates a tricky install.

Pin Hole

The pin has multiple O-rings and requires a special touch to avoid pinching during installation. Great care must be taken in the removal of the old hydraulic trim tab cylinders and the re-installation of the new ones. Damage to the assembly as a result of scratching or scoring the unit would cause them to leak and render the trim tab cylinders useless.

We see these types of nuisances all the time. It takes a team of highly experienced hydraulics technicians to properly diagnosis the problems and take the appropriate actions to correct them.

Giving an Old Hydraulic Royal Boarding Ladder a “Face Lift”

From time to time, we see some pretty old yachts come into Lauderdale Marine Center as was the case with a 30+ year old Feadship. This old gal was in need of some work to bring her back to her glory days. We were hired to give her hydraulic royal boarding ladder a “face lift.”  A hydraulic royal boarding ladder is side mounted typically at mid-ship that retracts using hydraulic folding mechanisms when not in use, leaving your deck free of obstacles.

The job included stripping the boarding ladder for a new paint job, replacing the hydraulic hoses and hydraulic cylinders and installing new hardware right down to the nuts and bolts.

The royal boarding ladder now looks brand new with no traces of 30-odd years of use.

Working on a 26T Crane takes special tools, equipment, coordination and expert experience

The captain of a 215’ Expedition recently contracted our hydraulics team at High Seas Hydraulics to work on the vessel’s crane. This particular yacht is a shadow boat hired out to “shadow” luxury yachts ferrying extra crews and other “toys” the luxury yacht owners or guest may need on their extended voyages. Those toys can range from large tenders to cars to even a helicopter.

The two luffing cylinders on the crane were leaking hydraulic fluids at the seals and needed resealing before the vessel went out to sea again. The catch on this job was the size of the crane, the weight of the cylinders and the timeline to fix. We had just one week to pull, diagnose, fix and re-install the luffing cylinders on this 26 ton crane, the largest crane we have worked on at High Seas Hydraulics. Each luffing cylinder weighs over a ton and needs special equipment to handle.

Coordination was key to ensure this job went smoothly. We first had to rent scaffolding that needed to be erected on the aft deck in order for our hydraulic technicians to reach and secure the cylinders for removal from the boat. We then rented a boom truck with a 73 foot reach from a local business to remove the luffing cylinders from the yacht and place on our sister company, Straight Line Marine’s flatbed truck for transportation back to the shop. Having a flatbed truck as part of our fleet comes in handy for these types of jobs as well as moving large shafts from mega yachts.

Once back in the shop, we inspected the luffing cylinders and sent them out to be resealed. The company that we contracted to reseal the luffing cylinders was unable to pressure test the luffing cylinders due to equipment problems so they were returned to High Seas Hydraulics. Fortunately, we have the proper equipment and experienced technicians to perform the testing in house for these cylinders that required 2,500 pounds of pressure.

Communications is key

Upon completion of the service work and testing, we returned the luffing cylinders to the yacht using our flatbed, brought the rental boom truck back and re-erected the scaffolding. Here is where the real precision work comes into play. While the boom truck does the heavy lifting, our hydraulic technicians guide the cylinders into place using safety line, straps and chain come-along ratchets. Communications with the crane operator is crucial and is most often done with hand signals.

We first secured the lower end of the cylinders into the crane and pinned them into place while they were still attached to the boom truck crane. Installing the pin on a crane of this size takes balance and a little brute force! Once in place, we released the straps from the boom truck crane and using straps and the chain come-along ratchets, raised the luffing cylinders into place for securing the top to the crane. We then reattached the hydraulic hoses to the yacht’s crane so we could use the boat’s hydraulic power to extend the luffing cylinders for the final pin installation. While this work takes experience and knowledge of the process, performing the task while standing on scaffolding more than 10 feet of the deck adds to the complexity.

Once the luffing cylinders were firmly and securely in place, we re-installed the rest of the hydraulic hoses and tested the crane to ensure that it was working properly for the demanding tasks it undertakes while at sea.

This was a big job with a tight timeline that we were able to push through so the captain could meet his charter schedule. This shadow boat is ready to set sail with those “little extras” that help to make memorable adventures.