Innovative Manufacturing Technology

Manufacturing enclosures as monolithic components is a characteristic feature of the technology applied by Strunobet-Migacz Sp. z o.o. The container consists of independent components which are the cable of the basement, the main body and the roof. Depending on the equipment and field of application, the enclosures can be made as compact ones (operated from the outside) or container ones (operated from the inside).

Main body

The main body of the enclosure of a transformer station is a monolithic system of four walls and a floor. The floor separates the transformer and switchboard compartment from the inner space of the cable basement.
The transformer and the switchboard rooms are separated by a partition made ​​from perforated or solid sheet in an angle frame. There is also an alternative of using a partition made of reinforced concrete slab fixed to external walls and the floor.
The enclosure is made from the SCC self-compacting concrete class C 30/37.
Casting of the enclosure is performed in an inverted position. The walls are cast together with the floor, which forms a solid monolith.
Openings for doors and grates are made in the main body while the openings for cables are made in the floor.
Inside, the walls are covered with white or other bright colour decorative acrylic plaster. Outside, the walls are also covered with acrylic plaster. The colours and types of elevation are offered in a standard version (see manufacturer’s catalogue). For the enclosure, it is also possible to use the colours and type of elevation according customer’s needs.
Increased degree of REI 120 protection is achieved by the use of PROMATEC plates fixed to the walls on the outside of the enclosure.

Cable Basement

The cable basement is made as a uniform prefabricated component with the dimensions adapted to the freezing zone of the ground, which constitutes the foundation of the station at the same time. The cable basement is made from the SCC self-compacting concrete class C 30/37.

The cable basement has a partition which is 300 mm high and is made in order to section off a part of the basement as a “bath” that can hold the entire (with some margin) oil from the transformer. Upon customer’s request, the partition can be as high as the basement and it can be made in the amount specified by them. The surface of the oil pit is covered with 2 layers of an oil-protective paint. The side walls have permanently cast in sleeves, such as plastic ones, which are cable and earthing penetration sleeves. On the surface, the exterior of the cable basement is covered with special bi-directional waterproof and oil-proof agents.

Roof

The roof of the enclosures is made as a rectangular reinforced concrete plank with variable thickness needed to form a 2.2% decrease in the direction of the bigger dimension. This edge requires the minimum thickness of the roof plank of 90 mm​​, and the maximum span in the middle of 130 mm. The roof plank is made from the SCC self-compacting concrete class C 30/37. Intricate components such as the roof verge or the eaves are additionally reinforced.
The roof is mounted directly on the walls. An elastomer background layer between the wall and the roof of the enclosure creates an air space which is a natural draft ventilation of the station. The roof is arranged freely. Therefore, in case of an arc fault it has the ability to go up, forming an outlet for the pressure and the post arc gases and particles, and then it falls freely to its former position.
The outer surface of the roof is painted with sun and rainwater resistant paint. Additionally, it can be covered with a layer of roof paper.
In order to adjust the shape of the roof to the architectural requirements, the overlays can be made in the form of double-pitched or pyramidal caps covered with tile sheets or ceramic tiles.