Fire protection water storage tanks

Steel ground fire tanks are made of the highest quality materials, in accordance with fire protection standards and quality and safety standards. We make fire protection tanks in accordance with the following standards:

• EUROCOD, including PN-EN 12845 "Fixed firefighting systems - Automatic sprinkler devices. Design, installation and maintenance". 
• VdS CEA 4001 "VdS-CEA Guidelines for Sprinkler Systems. Design and installation”
• NFPA 22 "Standard for Water Tanks for Private Fire Protection" 
• FM "Water tanks for fire protection". FM 4020 
• PN-B, including PN-B-02857: 2017-04 "Fire protection of buildings. Fire water tanks. General requirements".

We are able to provide steel ground fire protection tanks with a wide range of dimensions and capacity. You can easily match the appropriate tank to the specificity of the installation place, design requirements, operating conditions or its assignment.

It is possible to design and manufacture tanks with non-standard dimensions and capacities.

Steel aboveground fire protection tanks designed and manufactured by SD Tank, consist of the highest quality hot-dip galvanized steel elements. The coat of the tanks is made of individually twisted steel sheets of standardized dimensions. The steel sheets thickness depends on the standard and the dimensions of the tank. The parameters of metal sheets are selected on the basis of strength and static calculations.

The metal sheets we use to build the structure are made of double-galvanized S350GD steel, coated with a zinc coating Z275, Z350 or Z600. The panels are drilled and the vertical and horizontal joints between the sheets are screwed together.

Thanks to the optimal selection of the zinc coating based on the calculations, we are able to design and manufacture durable tanks with the longest possible service life. When we design a tank, we calculate service life of the tank structure based on the corrosivity class of the location where it will be installed. Top and bottom edge of the tank construction is equipped with a perimeter angle which ensures rigidity and durability of the structure.

All steel structural elements and additional equipment of steel ground fire tanks are protected against corrosion using the hot-dip galvanizing method. Thanks to the zinc layer, it is possible to comprehensively protect the tank against the effects of unfavorable weather conditions. Additionally, at the customer's request, we can paint the outer parts of the tank coat by using the electrostatic method. In this way, the tanks gain an additional layer of protection.

The roof is made as a self-supporting structure laid on steel "Z-shape" beams with a slope to the outside. The roof structure ensures efficient and effective removal of snow and rainwater out of the tank. Additionally, the roof of the tank can be equipped with an insulated or non-insulated cover. The insulated cover is made of T35 trapezoidal metal sheet or sandwich panels insulated with a core of mineral wool, PIR foam or polystyrene. The covering width of the roof panels is 1150 mm, thanks to which they ensure quick, simple and convenient installation to the roof structure using pass-through fasteners. The tongue-and-groove joints make the roof tightly connected to the whole structure of the steel ground fire protection tank. We additionally use strengthening around the tank, the so-called "wind reinforcements" if required as a result of the statistical and strength calculations.

Providing easy access to the tank roof, we install a steel ladder with platforms on its structure. There is also a hatch on the top, which enables the fire protection tank interior inspection.

As part of the waterproofing protection, we use a prefabricated EPDM membrane or a PVC film welded at the construction site. Each of these solutions eliminate the risk of contact of the stored water with a thermal insulation or steel walls of a tank, thus preventing corrosion centres.

EPDM membrane 

• thickness: 0,75mm -1,00 mm, 
• guaranteed service life of min. 30 years, 
• very good properties in terms of expansion and contraction in the range of up to 300% elongation, 
• delivered to the construction site in the form of a ready-to-install bag, adapted to the dimensions of the tank, assembled on site, 
• 14 days for replacement in case of leakage.

PVC film

• thickness: min. 1,5 mm, 
• guaranteed service life of min. 35 years, 
• high resistance to mechanical damage, 
• vulcanized on construction site,
• 24 hours for replacement in case of leakage.

The membrane is protected against puncture by a geotextile with a minimum density of 150 g / m2, laid directly on the tank basis.

The thermal insulation of steel aboveground fire tanks consists of internal or external insulation and anti-frost protection.

External insulation

External insulation is used in the case of aboveground steel fire tanks covered with corrugated or trapezoidal sheet. The walls of the tanks are insulated with 100 mm thick mineral wool and additionally covered with a galvanized trapezoidal sheet. Instead of galvanizing, the trapezoidal sheet can be painted in a color selected from the RAL palette.

Internal insulation

Installed on the roof and walls of the tank. Usually it is made of EPS boards not less than 60 mm thick or XPS boards 40 mm thick. The plates are installed with screws between the membrane and the construction plate inside a tank.

Anti-freeze protection

Steel aboveground fire protection tanks are usually equipped with anti-freeze protection, consisting of 2-3 independent heating batteries with a thermostat, which generates power from 3 to 6 kW. The heating batteries operate in a three-phase system (400 V power supply). The degree of protection of the thermostat terminals and electrical connections has the IP 67 standard.

The heaters are equipped with automatic thermostats that regulate and maintain water temperature in tanks at a level not lower than 5oC. If the heater fails, it is not necessary to empty the tank completely.

Aboveground steel potable water storage tanks are equipped with automation and control systems. One of them is a system that monitors 4 water levels. This system consists of internal conductance probes suspended at appropriate levels of a tank. The signals generated by the probes are led to the relay implemented in the switch cabinet. 

On the roof of a tank, there is a Pt100 sensor suspended 1 m from the roof level, which continuously measures temperature. The sensor transmits an analog signal about temperature inside a tank to the controller implemented in the switch box. Water level monitoring system monitors water level in a tank in 4 preconfigured modes:

• Minimum level - level of the minimum tank filling, which signals starting of emptying a tank to the lower dead zone. The probe informing about this mode is placed 50 mm above the edge of the suction pipe anti-vortex plate. An alarm triggered by a probe indicating the minimum level, prevents the pumps from dry running (running without water).
• Intermediate level - level of half (50%) filling of the tank. It is useful to be signaled during service and repair works on the tank. The intermediate level may indicate a different water level.
• Maximum level - the level of the maximum permissible filling of the fire protection tank, which enables its operation and effective fire protection of the facility. Lowering the maximum level is a signal that the water system is out of order. If the water level drops below the maximum level, the automation system will turn off the heaters.
• Overflow level - the level of the highest, alarm filling of the tank. If the fire protection tank reaches such a level of the water surface, it means that the float valve fails. If the overflow level is reached, the water from the tank may overflow.

All levels of water level monitoring system are signaled with red lamps in the tank operation controller located in the switch box. 

The switch box is usually installed in the pumping station building, which allows for constant supervision over the operation of electrical devices and automation systems located inside the fire protection tank. The water tank controller is usually installed on the wall, outside of the tank or in the pumping station building. It enables constant monitoring of the tank's efficiency. If any irregularities are detected, an alarm is triggered  to inform about the occurrence of faults or failures. The device complies with the IP 65 standard. 

The heating system turns on automatically when the water temperature in the tank drops below 5oC and turned off when it reaches the temperature of 6oC. If water in the tank reaches temperature of 3oC, the heating control system will signal the failure with a red "low temperature" indicator. The heaters turn off automatically when the water level in the tank drops below the maximum level. This is to protect the internal insulation layer of the tank.

Steel aboveground fire tanks are equipped with the necessary design equipment. The equipment is properly installed and its parameters are determined by the applied standard of execution and the pipelines requirements. 
The standard equipment of ground fire protection tanks consists of: 

• supply pipeline terminated with the so-called free outlet, 1-2 automatic float valves responsible for automatic filling of the tank (not required by law), 
• test and return pipeline, 
• suction pipeline with double anti-vortex plate,
• suction pipeline for Fire Service with manual throttle and STORZ suction hose coupling,
• overflow pipe, 
• cooling pipeline, 
• drainage pipeline with a manual shut-off damper. 

Each pipeline may be led through the foundation or tank wall, according to the requirements. F
ire protection tanks are additionally equipped with: 

• electrical switchboard, water level probes and heaters, 
• bottom service hatches (for tanks compliant with FM and NFPA standards), 
• in accordance with the current health and safety regulations, steel cage ladders leading to the roof, platforms with protective barriers, service hatches on the roof.

Designing

Before delivering the fire tank to the site and its installation, we make a detailed design of both the tank and the foundation slab. Along with the detailed design, we provide the necessary documentation, which includes, among others a design of a tank construction.

Delivery

After designing a fire protection tank we deliver it with the necessary equipment and unload the tank at the construction site or in the customer's warehouse. Usually, the day of delivery is a day of assembly start-up.

Assembly

Our team of 3-4 people assemble the tank by means of external hydraulic pistons. The steel structure with internal insulation, membrane and equipment is sequentially installed. The tank is fixed to the foundation plate with anchors. The foundation plate is also the bottom of the fire tank.

Leak test

After the assembly is completed a tightness test is performed. It consists of filling the tank with water to a height of approx. 1.5 m. At this stage the tightness of the pipelines flanged connections are checked. In the second tightness test, a tank is filled in to its nominal capacity. The second leak test lasts 24 hours and allows us to verify the tightness of a tank accurately.

Electrical devices commissioning

When a tank is already finished an electrical devices are stared-up. Our experts verify the correct operation of electrical devices and installations along with the automation systems necessary for the correct operation of a fire tank.

Warranty

The whole works are completed with the delivery of as-built documentation with the materials approvals and a warranty card.

Thanks to the developed tank assembly system, we are able to significantly reduce the need for heavy equipment and we can install the tank in the shortest possible time.

1. Step - site preparation

In the first step, we prepare the area for pouring a concrete foundation slab on which the tank will be installed. During this stage of works, we pour the slab and deliver all the necessary building and construction materials to the construction site to erect the tank.

2. Step - tank assembly

In the next step of works, qualified employees of SD Tank Sp. z o.o. start assembling the tank on a dry and ready-to-install foundation plate. Our tanks are installed using external hydraulic pistons. The steel structure of a tank is assembled in stages along with the simultaneous installation of the internal insulation, membrane and the tank equipment.

3. Step - finishing works

In the third step of a fire tank assembly, an external piping of a tank with its optional additional equipment is installed. After this assembly step, we proceed to leak tests, start-up of electrical devices and issue as-built documentation.

We provide a 5-year warranty for a tank construction and a 24-month warranty for mechanical and electrical devices. In order to maintain a warranty, it is necessary to perform at least one technical inspection with cleaning the membranes in the third year of operation of a tank from the date of its first filling with water.

You can extend the standard warranty period up to 15 years on the basis of a Full Service Contract.