Ubag – Heavy Duty Service Subsea Construction and Support Bag System

Home / U-System Products & Rental Equipment / Ubag – Heavy Duty Service Subsea Construction and Support Bag System

The Ubag system is a high strength, durable, heavy duty service subsea bag system available in a variety of geometries, sizes, weights, and configurations, that are installed separately or in combinations. Ubags are available for purchase or hire.

Applications are stabilization, protection, construction, support, separation, weight or counterweight, local insulation, levelling or levelling adjustment, rock dump stabilization or side support, landing support, scour protection or prevention including filter stone bags, etc. The following Ubag types are available:

  • Ubag – 1-cylinder bag – Type A1 & A3.
  • Ubag – Two-cylinder and multi-cylinder bags – Type B.
  • Ubag – Large size bags – Type C.
  • Ubag – Other type bags – Type D, E and F.
Ubas - ROV baskets

Ubag – 1 cylinder bag – Type A

Single cylinder Ubags available in two standardised width / height combinations. The length and weight are optional.

Type A1; 22cm high, 42cm wide and the lengths are 35cm, 65cm, 95 cm etc up to 3.05m. Typical dry weight is 25kg, 50kg, 150kg etc. up to 250kg (filled with sandbags).

Type A3; 40cm high, 60 cm wide and the lengths are 65cm, 95 cm, 1.25m etc. up to 3.05m. Typical dry weight is 150kg, 225kg, 300kg etc. up to 750kg (filled with sandbags).

The above dimensions are for Ubags that is laying on the seabed.

When filled with sand or gravel the dimensions are cylindrical and the weight is higher. E.g. a 4.0 m long Ubag with diameter 0.6m weigh 1810kg.

The bags are provided with heavy duty Velcro as the primary closing feature. Additionally they are provided with straps/ loops for secondary closing.

The bags are provided with ROV handles (smaller and not to heavy ones, 200kg or less). Larger size Ubags includes integrated webbing straps / slings for handling and lifting.

Typical dimension and weights: Varies.

Other sizes are available on request.

Datasheet includes further details.

Ubas - ROV baskets

Ubag – 2 or Multi cylinder bags – Type B

The two-cylinder and multi-cylinder bags are available in various sizes, and when laid on the seabed act more as a mattress.

The bags are filled with either gravel, sand or with 25kg sandbags.

Type B2; Two-cylinder Ubag, thickness / height is 22cm, 80cm wide and the lengths are 65cm, 95cm, 1.25m etc up to 3.05m. Typical dry weight is 100kg, 150kg, 200kg, 250kg etc up to 500kg

Multi-cylinder Ubag thickness / height is 22cm, and the width is 2.0m. The lengths are 1.15m (Type B3), 1.5m (Type B4), 1.85m (Type B5), etc up to 3.6m (Type B10). Typical dry weight is 450kg, 600kg, 750kg, etc up to 1500kg

The above dimensions are for Ubags that is laying on the seabed.

The bags are provided with heavy duty Velcro as the primary closing feature. Additionally they are provided with straps/ loops for secondary closing.

The bags are provided with ROV handling loops (smaller and not to heavy ones, 200kg or less ).

Larger size Ubags includes integrated webbing straps / slings for handling and lifting.

Typical dimension and weights: Varies.

Other sizes are available on request.

Datasheet includes further details.

Ubas - ROV baskets

Ubag – Large Size Bags – Type C

The large size Ubag are available in various sizes and with various weighs, These are generally sized to suit the clients requirements.

The bags are filled with either normal gravel, sand, standard 25kg sandbags or larger standard big bags.

Typical sizes and dry weighs are: Type C-2,5T: 2 500 kg (dry) & 1m x 1m x 1.5m (W x D x H) Type C-3,5T: 3 500 kg (dry) & 1.7m x 1.7m x 0.75m (W x D x H) Type C-8,5T: 8 500 kg (dry) & 2.0m x 2.0m x 1.35m (W x D x H)

The bags includes integrated webbing slings for handling and lifting.

In order, maintain the geometry of the larger bags, they are filled with 25kg sandbags or standard big bags with a suitable size/weight. In addition, the bags include webbing /‘belly’ straps sewed onto the circumference of the bags at different elevations. In cases where the geometry / shape of the bag are ‘critical’, the inside walls of the bag are stiffened up with 38mm GRP gating.

The bags are provided with industrial type zip as the primary closing feature. Additionally they are provided with straps/ loops for secondary closing.

Typical dimension and weights: Varies.

Datasheet includes further details.

Ubas - ROV baskets

Ubag – Other Types

The Ubags are also available in other geometries and configurations.

Type D: ‘Shopping bag’ / Sack type Ubag. 25 kg sandbags are placed in these bags and then they are closed. The bag provided with a ROV handle. This type of Ubag permit ROV placement of 4-8 sandbags in one operation. Furthermore, vulnerable sandbags are placed within a strong durable bag. Two sizes are available. That is for 4 sandbags and for 8 sandbags.

Type E: Block Type Ubag. These bags are rectangular / cubic. The size is 0.3m x 0.3m x Length. Available lengths are 0.4m, 0.8m or 1.2m. The block bags are provided with ROV handling loops. The sides of these Ubags are supported by 38mm GRP grating that are placed on the inside of the bag. The bags are filled with standard 25 kg sandbags.

Type F:Filter Stone / Scour Protection Ubag. These bags are similar to the Type B2, 2-cylinder Ubag and the Types B3-B10, multi-cylinder Ubags. The difference are that a high strength coated polyethylene net has replaced the fabric on one side of the bag (2.5 x 2.5 cm net openings). When placed on the seabed with the fabric side down, the fabric will prevent the rock from sinking into the seabed. On side exposed to current the 10cm diameter, crushed rocks will break up current / trap flowing sand thereby reducing any potential scouring. The individual rocks are contained in the bag with net, and the weight of the whole bag keep them in place.

The two-cylinder filter stone bags are provided with ROV handling loops (smaller and not to heavy ones, less than 200kg). Larger size bags includes integrated webbing straps / slings.

The bags are provided with heavy duty Velcro as the primary closing feature. Additionally they are provided with straps/ loops for secondary closing.

Datasheets are available on request.

Ubas - ROV baskets

Ubas Basket for deployment of Ubags

In the case of a larger number of smaller Ubags that shall be deployed at the same location, the Ubags can be delivered loaded into an Ubas ROV basket (rental), ready for deployment.

Datasheet includes further details.

Ubas - ROV baskets

Ubag Ballast Sling Assembly

In cases where additional weight is needed for deployment of equipment, e.g. unfolded light weight Umat Mattresses, a ballast sling assembly that includes an Ubag can be used. This sling assembly includes (starting at the top), shackle, 2 t webbing sling, Ustrap ROV release link, shackle and Ubag. The ballast sling assembly is retrieved together with the deployment sling. It is released from the equipment by ROV pulling the Ufist attached to the Ustrap release link (i.e. noting to cut with ROV knife, or no ROV shackle to operate).

As the Ubag is sand filled it minimize the risk for damaging other equipment in case of contact between the bags and the equipment).