Under modern conditions, the issue of transferring newly built vessels from shipyards to their home ports has become particularly acute. This is due both to river shallowing and a trend where shipyards win construction tenders for vessels whose lightship drafts exceed the depths of the navigable fairway.

A unique pontoon system (specialized technological equipment) was first designed in 2009 by specialists from the SeaTech Design Bureau. It was developed to facilitate the shallow-water passage of vessels with drafts up to 3.2 m through the Oka River, where the fairway depth is approximately 1.8 m.

This unloading pontoon system, designated as Project 20360PP, consisted of two pontoons connected by tie rods (each measuring 46.2 x 6.0 x 3.75 m) and was originally intended for a vessel with a displacement of about 1,500 tons. The system successfully maintained the draft of the combined vessel-pontoons assembly within the fairway limits.

In 2016, the next modification of the pontoon system—Project 250PP—was designed and built for the transfer of high-speed, deep-V hull vessels with a displacement of about 240 tons. The dimensions of a single pontoon are L x B x H = 34.8 x 5.6 x 4.4 m.

The development of specialized technological equipment for the transit of various vessels continued in subsequent years.

................

June 2026. A technological solution has been implemented for the transit of the multifunctional supply vessel D. Konaev.

A complex technical phase has been completed for the transfer of the new Project P4240 multifunctional auxiliary supply vessel, D. Konaev, built at the Zenit shipyard, from Uralsk to the Caspian Sea. Specialized technological equipment developed by the SeaTech Design Bureau played a key role in the successful transit of the vessel.

The technology enabled the passage of the vessel, which has a design draft of 3.5 m, through river sections with depths of less than 1.5 m. The logistics were organized taking into account dimensional restrictions, including the dismantling of the mast for passage under the bridge in Atyrau. Final outfitting is scheduled to take place at the Port of Aktau, after which the vessel will be delivered to the customer.

We appreciate the opportunity to apply our technologies in real-world conditions and continue working on their improvement.

Unique features of the vessel-pontoons complex:

* The vessel is secured on the pontoons by its own weight without the need to weld structural brackets to the vessel hull.

* After ballast is pumped out, the vessel is additionally clamped by the pontoons along its sides, turning the entire system into a single unit.

* A water area depth of just 0.4 m more than the vessel draft is sufficient for docking the vessel onto the pontoons.

* Asymmetric L-shaped pontoons are connected by a flexible coupling system, which simultaneously provides both mobility and rigidity to the entire structure.

* The vessel is placed on wooden keel blocks, making the pontoon system highly versatile for vessels with various hull lines.

The pontoon system is simple to manufacture and operate, and the pontoons do not require expensive ballast equipment. The use of such structures helps solve a wide range of tasks—from delivering a vessel from the shipyard to the customer, to relocating fleets across inland waterways.