Bladder tank. How to reduce risks when purchasing and operating a bladder tank?

Bladder tanks are widespread in domestic fire extinguishing installations since the early 2000s. Simplicity of construction, clear operating principle and various modifications have attracted customers. Demand for imported bladder tanks led to the development of Russian production. The cost and apparent ease of use of the tank are the main advantages. However, today the bladder tank is not a product determined by GOST. There are certain risks associated with this for customers and operating organizations.

Pozhneftehim, a Russian manufacturer of equipment and foam concentrates for foam fire extinguishing units, tells about the technical requirements for bladder tanks. It is necessary for customers and operating organizations to know about them, so that the proportioning system works correctly during its operation life.

Content

• How does the bladder tank work?
• Basic equipment of the Antifire bladder tank manufactured by Pozhneftehim
• Additional equipment for the Antifire bladder tank manufactured by Pozhneftehim
• Automation Control cabinet of bladder tank, ShABD
• Operating and nominal pressure of the bladder tank
• Operational documentation for the Pozhneftehim bladder tank
• Training and Advanced training courses on foam fire extinguishing units

How does the bladder tank work?

Pozhneftehim has been manufacturing Antifire bladder tanks since 2010. The company has its own production base in the Tula Region, as well as a hydraulic test stand for quality control of products as part of foam fire extinguishing units.

There are two types of bladder tanks:

• Standard bladder tank with calibrated diaphragms
• Bladder tank with a wide range dispenser

Let’s consider the key elements of a standard Antifire bladder tank in a schematic diagram.

DIAGRAM

The bladder tank consists of a tank, inside of which there is a flexible container for storing foam concentrate. The dosing system starts to work when water begins to flow into the dispenser. Part of it along the line of water supply to the tank squeezes the foam concentrate into the line of foam concentrate supply to the solution. Further, a special calibrated diaphragm of the dispenser, configured for a proportioning ratio of 1%, 3% or 6%, ensures the flow of the right amount of foam concentrate into water. Thus, a working solution of a foam concentrate is obtained. Then it enters through a solution pipeline to a foam generator, which is used for the formation of air-mechanical foam of low, medium or high expansion.

Basic equipment of the Antifire bladder tank manufactured by Pozhneftehim

• Tank with internal flexible container
• Dispenser with piping arrangement
• Ball valves on the lines for supplying water to the tank and on the line for feeding the foam concentrate from the tank to the dispenser
• 1.6 MPa safety valve on the water supply line to the tank
• The backpressure valve on the line of foam concentrate supply from the tank to the dispenser
• Nozzles for refilling the tank with foam concentrate, hydrometer
• Pressure gauges on the dispenser, the line for supplying the foam concentrate from the tank to the dispenser and at the outlet of the dispenser

Additional equipment for the Antifire bladder tank manufactured by Pozhneftehim

• Automation Control cabinet of the bladder tank (ShABD)
• Electric heating in general industrial or explosion-proof design
• A flow meter (discrete or analog) on the water supply line to the tank, which allows to determine how much foam was "squeezed out" of the internal flexible container
• Filter on the water supply line to the tank to protect the internal flexible container
• The concentrate control valve on the line of supply of the foam concentrate from the tank to the dispenser
• Flow signaling device on the line of supply of the foam concentrate to the main tube
• KOF, a set of counterflanges and fasteners for connection to a main water line
• Electric centrifugal pump for filling the bladder tank with suction and pressure hoses, units for connecting to an intermediate bulk container and a filler neck
• Pressure gauge to control air pressure when refilling
• Reserve internal flexible container
• Reserve dispenser with twine tying (with manual or automatic control)
• Air compressor
• Electric hydrometer with a discrete signal, with a safety valve against overpressure

The choice of design (vertical, horizontal, double), material performance, dosing percentage, flow range and equipment is carried out at the stage of filling out the Pozhneftehim questionnaires.

Automation Control cabinet for bladder tank, ShABD

The Control cabinet of the bladder tank is necessary to measure, display and archive information about the level of the foam concentrate. ShABD in real time provides information on the volume of the foam concentrate in the flexible container of the bladder tank. The automation cabinet can be used with all types of bladder tanks from 100 to 65.000 liters.

The automation Control cabinet of the Antifire bladder tank is equipped with a text LCD, has password protection for settings against unauthorized access, stores an archive of events and is compatible with flow meters regardless of the value of the pulse signal. Information can be output to the automatic process control system in different ways: analogue signal, discrete and interface (RS-485).

The installation of ShABD allows fulfilling the requirements of SP 5.13130.2009, as well as GOST R 50800, clause 5.1.12 on emergency level control. Using the automation cabinet makes the operation of the bladder tank, especially when filling and refilling, more convenient. ShABD provides automatic control over the state of the dosing system and facilitates the management of the fire extinguishing system.

Operational and nominal pressure of the bladder tank

To ensure stable operation of the bladder tank as part of the fire extinguishing system, the nominal pressure must be selected according to the requirements of the customer. Confirm the compliance of the product with the declared technical parameters at the factory tests including the pressure range. A manufacturing company can submit the results of hydraulic tests that confirm that the product is designed to produce a foam solution with desired proportioning ratio.

The dosing system is responsible for the fire-fighting capacity of the fire extinguishing installation. If the manufacturing company does not have test facilities and cannot verify the operation of the bladder tank for basic technical parameters, this means that the customer cannot be sure that the product meets the requirements of its fire extinguishing system.

In the Russian market there are bladder tanks configured at 1.2 MPa. Pozhneftehim bladder tanks operate in the range from 0.6 to 1.4 MPa, and the required pressure is selected for the technical requirements of the system. The product is manufactured and tested at the Pozhneftehim hydraulic test stand for a specific operational pressure of the Customer.

Operational documentation for the Pozhneftehim bladder tank

The manufacturer, upon delivery of the product, provides the customer with a set of documents. They are needed for acceptance testing by the Customer's Quality Department. The lack of a set of documents may lead to comments from supervisory authorities.

Upon delivery of the Antifire bladder tank, Pozhneftehim provides the following maintenance documentation:

• maintenance manual (mandatory);
• vessel passport, drawn up in accordance with the requirements of section IV of paragraph 21 of TR TS 032/2013 “On the safety of equipment operating under excessive pressure”. The passport indicates the methodology, frequency and scope of the vessel control, the implementation of which will ensure the timely detection and elimination of defects (upon request);
• certificates of quality and characteristics used in the manufacture of materials (upon request);
• documentation for the internal tank coating, soil, enamel (upon request).

Approval documentation for bladder tanks includes the following:

• Certificate of conformity issued by an accredited body of the Ministry of the Russian Federation for Civil Defense, Emergencies and Elimination of Consequences of Natural Disasters (required
• Declaration of conformity and compliance with the requirements of the design documentation for compliance with GOST 52630-2012
• Certificate (declaration) for compliance with TR TS 032/2013 (required).
• The safety justification (SJ) specified in paragraph 45 of TR TS 032/2013 (upon request).
• Certificate (declaration) of conformity of the safety valve TR TS 010/2011 in the bladder tank (according to Appendix No. 3 of the TS TS 010/2011 safety devices are subject to declaration of conformity separately) (upon request).

A set of documents demonstrates the company's attention to product quality.

Photo: Pozhneftehim LLC © 2004-2018 Bladder tank in the Vityaz fire-fighting block container. Photo at the factory in Donskoy, Tula Region

In addition to these documents, the customer receives a factory test report of Pozhneftehim, which confirms that the bladder tank is suitable for a specific fire extinguishing system. In addition, Pozhneftehim undertakes warranty obligations for the purchase of a bladder tank in combination with the Aquafom foam concentrate manufactured by Pozhneftehim.

Additional services of the manufacturer Pozhneftehim include filling and refilling of the bladder tank, staff training, installation supervision, as well as participation in commissioning, verification and acceptance tests. Consultations of Pozhneftehim specialists at different stages of the implementation of the fire extinguishing unit and its maintenance will reduce the risk of damage to the bladder tank and ensure its uninterrupted operation during the service life.

Training and Advanced training courses on foam fire extinguishing installations

If you want to learn more about the operation of foam fire extinguishing installations and systems, we invite you to Pozhneftehim Advanced training courses. The theme of the course is “Modern foam firefighting technologies at the facilities of the oil, petrochemical and gas industry”. The course program is available on the website of Pozhneftehim www.pnx-spb.ru.

During the courses, we discuss the features of fire extinguishing systems, fire equipment and foam concentrates that are available on the Russian market, we demonstrate the operation of fire extinguishing systems with low, medium and high expansion foam with Aquafom foam concentrate of our own production. The training is conducted by Pozhneftehim LLC under the License of the Ministry of Education of the Tula Region No. 0133/03315 dated September 30, 2016.

The article is published on the site protivpozhara.com

The material was prepared by specialists of Pozhneftehim LLC
Contact for further advice: +7 (499) 703 01 32, mail@pnx-spb.ru