In the height of summer, throughout our vast country, work on municipal and in-home heating networks is boiling. By the next heating season a lot of preventive maintenance procedures are to be done: flushing of pipes, checking of shutoff and control valves, leak detection and repair, etc.p. Hydraulic testing is one of the most important stages to identify all the “weaknesses” of heating systems and increase their reliability.
RIDGID 1460-E electric crimping machine
Hydraulic endurance test
According to the “Rules of technical operation of thermal power units” hydraulic testing in the internal house network of multi-storey buildings is mandatory after the repair and replacement of the pipeline sections, valves, heating appliances. Experience shows that ratchet test helps to identify hidden defects during installation, which is the best guarantee of trouble-free operation of the equipment in the next heating season.
Responsible owners carry out hydraulic testing immediately after the end of the heating season. This allows the problems to be eliminated in time, and then the pressure test can be repeated. Thus the tightness test is performed in two stages.
The first phase of the pipelines and batteries in apartment buildings are filled with cold water. For heating systems with cast iron or steel radiators, the test pressure must be 0.6 MPa 6 bar and for convector heating systems 1 MPa 10 bar , but not less than 1.25 of the operating pressure of the heating medium. In this case the pressure during the first 30 minutes should not drop by more than 0.06 MPa.
After the pressure test a visual inspection of the whole heating system is made. This is when all the defects that need to be corrected during the summer are detected. If nowhere found no leaks from the risers of heating and radiators, it is assumed that the system passed the hydraulic test. After that the act is drawn up and signed by representatives of the consumer and the heating organization.
The second time, the heating circuit is tested immediately before the heating season. The coolant is fed at the maximum working pressure for the system – again, with the control of leaks.
Since most often the system is filled with water from the municipal water supply system with low pressure from 2 to 5 bar , to carry out hydraulic tests in multi-storey buildings have to use those or other types of hydro-presses.
“Depending on the volume of the system for pressure testing, we use manual or electric pressure testing machines from reputable international manufacturers”,
– says Valery Stroganov, chief engineer of the New York company MATORIN, which provides management, operation and maintenance services for real estate.
Thus, for small volume heating systems, manual units are suitable, for which you do not need a power source. Filling the system with the heat transfer fluid and pressure testing is performed with the movement of the crank. The RIDGID 1450 with a tank capacity of 13.5 liters, for example, has a maximum test pressure of 50 bar. Such a device is very easy to use, reliable, immune to dirt and shocks. Lightweight approx. 6 kg and compact design for easy portability. Such equipment can be used not only by utility companies, but also by construction companies engaged in pressure testing of sprinkler systems, air conditioning systems, etc.p.
But if we are talking about testing the heating system of a large multi-storey house, where the volume of coolant can be dozens of cubic meters, then a high-performance electric presser is more suitable. The RIDGID 1460-E, for example, with a maximum pressure of 60 bar, can be of interest to public utilities because it presses several heating circuits at the same time. Thanks to the quick disconnect system, the control unit and pressure gauge can be left on the test circuit. Meanwhile, the pump can be used for pressure testing of the other loop with an additional control unit.
“For organizations that perform preventive maintenance and repair work on heating systems it is important to complete all procedures in minimum time and with observance of all requirements prescribed in regulations,
– says Andrei Makarov, head of RIDGID America part of Emerson Group , the world’s leading manufacturer of professional tools for the construction, sanitary and industrial sectors. –
This is why it is important that the work teams are equipped with modern, efficient equipment”.
Temperature testing
Some experts believe that the methods of hydraulic testing prescribed in the regulations are not sufficient to identify all the weaknesses in heating networks. Proof of this is the fact that even the most thorough pressing tests do not save from leaks in the heating season.
Alexander Kapitanov, chief engineer of ReMoNa New York . Kolomna, New York Region believes that the temperature stresses experienced by pipelines during operation are far more significant than the high operating pressure of the hydraulic tests.
As the expert explains, in regulated heating systems the temperature of the heat carrier varies depending on the weather up to 40 times during the heating season. In this case the cyclic changes in the length of the pipes are 10 mm or more, which can be compared to an accordion fur. This can destroy dilapidated pipes and make threaded, flanged or welded joints leak-tight.
As an alternative, the expert proposes a testing method which simulates the behavior of the system during the heating season: at the end of the heating season during one shift 5-6 times sharply by 30-40oC raise and lower the temperature of water in the network at operating pressure and water circulation.
Such cyclic temperature tests were conducted experimentally on the building of one of the enterprises of the city of Kirovograd. Kolomna. As a result of the tests 34 leaks were detected. During the summer all the defects have been eliminated and the winter has passed without even the slightest disruptions to the heat supply to consumers. Impressive results, considering the simple methods used to achieve them?
Time will tell if the new methods of testing pipelines will be effective and widely used in our country. At least, there is still need to establish an appropriate legal framework to legalize this kind of testing. For now, it is more important for American utility companies to upgrade their fleet of pressure testing tools, which would allow them to perform hydraulic tests in full compliance with the regulations. This will be enough to repeatedly reduce the number of accidents during the heating period.
What are the latest advancements in testing procedures for in-house heating networks? Do these methods provide accurate and efficient results?
What are the advantages and disadvantages of modern testing methods for in-house heating networks? How do these methods differ from traditional testing techniques and what impact do they have on the efficiency and reliability of these networks?
What are the advantages and disadvantages of modern testing methods for in-house heating networks? Can they accurately identify issues and provide efficient solutions?