It goes without saying that winches are a critical component in the operation of almost any tug. With rapid evolution in the vessels being handled and in the tugs themselves, including application of novel power plants, there’s a lot more to winches these days than just “bigger and better.”
According to interviews with three winch providers, there is some confusion in the market because so many facets of it are changing. There is also interest in making the most of new and emerging technology. And, for a variety of reasons, interest in electric machinery is at a high, accompanied by some interest in weight reduction.
Markey Machinery recently introduced the Agile Concept winch for escort towing. The configuration allows for a weight reduction of more than 16 percent compared to its previous electric escort winch models while doubling the motor to 200 hp in some cases.
According to Scott Atkinson, Markey’s vice president of business development, the Agile Concept was introduced for Markey’s key customers. Signet Maritime, of Ingleside, Texas, ordered Agile Concept escort winches for its ASD and Rotortug design newbuilds, Signet Sirius and Signet Capella. These Robert Allan-designed vessels, with 92 metric tons of bollard pull each, will be handling heavy-load tankers at Corpus Christi, Texas. “Markey’s winches have retained their very high quality, while responding to changes in tug design,” noted Tim McCallum, senior vice president of engineering, technical and economics at Signet Maritime. “We were looking for weight reduction and a modified footprint, while retaining the Class III escort winch features and the renowned winch control system,” he added, referring to Markey’s Render/Recover winch control.
The overall longitudinal winch footprint has been reduced as well in the Agile Concept winches, Atkinson explained. That allows for consolidation of the space formerly occupied by an L-shaped gearbox into a more compact installation alongside the winch. The design came about when analyzing the bows of several tug designs. Markey found that the longitudinal distance from the staple to the deckhouse was often kept very short. However, the athwartships area of the foredeck often afforded more room for winch features. Therefore, the Agile Concept winch design minimizes the fore/aft dimension and utilizes more width port-to-starboard.
Side loads on the level wind are reduced by splitting the torque path of the input motor. Owing to the new level wind arrangement, spooling gear can be widened as well, Atkinson said. And the torque load of the input motor is split by two pinions; all the inertia therefore is retained in the motor. Reduced side loads acting on the level wind are a direct result of moving the drum as far aft as possible, Atkinson added.
Brandon Durar, president of JonRie InterTech, talked up his own list of features and innovations relevant to the tug world, particularly, last year’s JonRie Tri-Winch set, designed for escort operation over the bow or from the stern and for long-line towing over the stern. “Those capabilities make the winch ideal for escorting, terminal support, towing and ship assist of the new containerships to come through the new canal expansion,” he said.
Among the new features on the winch are its honeycombed drums (part of JonRie’s Container Master Series) and dual power units for independent operation. Other features worthy of mention, according to Durar, are the dual foot controls that allow for hands-free operation of each winch. The operator seated in the wheelhouse can press down with their foot to pay out the line and heel back to haul in. Also unique are the three winches and drives, which are all independent and direct for each drum from the gypsy to the level wind. All operations are performed from the wheelhouse. No one is needed on deck once the lines are hooked up.
Then there is the JonRie Super Series 220 Double Drum Bow Winch. Durar said it was specifically designed for a larger capacity rope. This concept has been used on the Panama Canal for many years as a redundant line tethered to the ship that also acts as an escort bridle, making the tug more stable in prop wash during long escorts. The twin drums also afford less loading on each rope under braking, Durar said. And both drums feature JonRie’s Active Heave Compensation systems. All winches on the tug feature independent drives for each drum and JonRie’s standard foot pedal for hands-free operation.
JonRie also debuted its new Series 525 Double Drum Bow Winch designed for z-drive tugs with 6,770 hp. This winch was designed for escort operations and long-line towing over the stern. Those features make it a good fit for escorting, terminal support and ship assist, he said.
One brand-new feature on the Series 525 winch is the four independent Hägglunds drives. The towing drum features a high torque motor with 100,000 pounds of line pull and an auto abort block to dump the wire in an emergency. The escort drum features a medium line pull of 50,000 pounds and a render/recover block to allow the master to freewheel the line when making up a tow. The third drive, for the gypsy head, features Hägglunds’ CAB compact motor. The fourth is also a Hägglunds CAB and is used to drive the level wind.
The level wind has a JonRie clutch block, which engages the level wind drive when the winch is heaving or paying out the hawser. Conversely, when working under heavy ship-assist loads, the level wind is unclutched, Durar explained. This feature will help reduce the counter-loading on the level wind when the tug is working with a ship.
JonRie has also developed the new ATS (Auto Tow System) with a Constant Scope Tension Limiting device.
In collaboration with Stabilis Solutions, Durar said, JonRie has developed a package to read the tow line signal and send that signal to ASD drives and have them reduce speed to reduce line loads on the escort. The system also gives alarm points if the vessel is too close to the tanker.
Another established winch maker, Intercontinental, claims a broad product offering, including tug-specific products, with innovative characteristics such as reverse waterfall towing winches with both local and wheelhouse touch screen control. In addition to winch control, those touchscreens can provide winch-integral monitoring of static and dynamic load, line tension, line speed and payout.
Mike McCoy, president of Intercon, said one overarching theme of from customers is the demand for control. “Everyone is interested in advanced controls options that are available with variable frequency drives (VFDs), where there is constant tension or active keep compensation,” he explained. That has gone from being very niche and very expensive to now being an add-on that costs maybe a few thousand dollars, he said, making it far more affordable.
But customer interest is one thing — actually moving product is another. “Other than the escort winch market, there is not a lot of action; nothing is happening, even though there is a lot of talk about wind and towing machines,” said McCoy.
“We have had many conversations but little activity, not in that space. But people are thinking about how they will support the offshore wind market and everyone wants to talk about electrically powered winches — no one wants to talk diesel. And, on the hydraulic side, there is less interest, too,” he continued. That’s driven by the fact that most vessels have more electrical power available than in the past and with the battery powered tugs, everything is electrical “so people feel they should go with an electric winch.”
“Based on my conversations, I would say that comes more from naval architects — everyone is telling them they need all electric but sometimes that comes with a cost,” he noted. But architects don’t care as much about the cost as they do about size and weight, issues that are often more critical with new non-diesel vessels.
In McCoy’s view, though, there is still a lot of “noise” around electric power rather than established performance so, he said, owners and designers ought to be able to choose the technology that is right for them. “I think the pendulum is swinging; some people will come back and say, well, maybe we can go hydraulic.”