Exploration on Technical Requirements and Measures to Ensure Safety, Sealing and Fire Extinguishing

(5) We are very strict in our purchasing of parts and components and in our production and quality inspection before our gas fire extinguishing products are delivered to make sure that our users have confidence in and rest assured about the quality of our products.

2. Good sealing, no leaking and long service life

The parts and components used for the fire extinguishing system product “Belt and Road” exporting project (also called gas fire extinguishing system exporting project, or gas fire extinguishing system exporting) must have good sealing performance and stable quality. To ensure good sealing performance and stable quality of the products for the fire extinguishing system product “Belt and Road” exporting project (also called gas fire extinguishing system exporting project, or gas fire extinguishing system exporting), we must do the following:

(1) All the valves of fire extinguishing agent cylinders for the gas fire extinguishing systems must be forged from cold-drawn brass rods to prevent corrosion and rusting, and ensure quick and reliable starting. After forging, the crystal particles in the internal microstructure of the copper valves become finer, increasing the density of the material and making the sealing of the valves of fire extinguishing agent vessels to last longer and more reliable. It overcomes the poor sealing and other serious defects of the cylinder valves made from the low-cost stainless iron due to fine heat cracks, loose structure and gas holes that appear inside and on the surface of the castings caused by impurity and difference in solidification temperatures and shrinkage during the cooling process.

(2) It is advised to apply both radial and end-face sealing structures to the valve seals and the joints of the parts and components of the fire extinguishing agent cylinder groups, using sealing materials that are resistant to both corrosion and high temperatures to provide double protection to the sealing property.

(3) Gas fire extinguishing agent filling techniques of agent cylinder groups are different and agent filling techniques can significantly enhance the agent cylinder groups’ one-time gas tightness test qualification rate to more than 99%, lowering changes of leakage, prolonging storage cycles, reducing users’ maintenance costs and improving safety guarantee for the users.

(4) Gas tightness test must be very strict on cylinder valves and fire extinguishing agent cylinder groups. After filling the agent, the whole cylinder group has to be submerged in clear water for gas tightness test, twice at least, each time for no less than ten minutes. If no single bubble is seen leaked from the cylinder, it is considered to be qualified. This kind of gas tightness test by submerging a fire extinguishing agent cylinder group in clear water is simple, clear and reliable. Many gas fire extinguishing system manufacturers do no perform this kind of gas tightness test by submerging the whole cylinder groups under water. They normally brush some liquid soap on the screw threads where valves are connected to see if bubbles appear. It is hard to determine if a cylinder leaks using this kind of method and sealing of the cylinders can not be guaranteed in this way.

(5) A switch structure needs to be installed in front of the pressure gauge of the gas fire extinguishing system and the switch must be easy to operate and reliable. The threads connecting the pressure gauges must be high strength, high precision and highly sealed dry-seal NPT to ensure reliable sealing.

（(6) There are two kinds of structures for high pressure connecting hoses: one has steel structure joints on both ends of the hose, one of which has a 90°elbow, and the flexible hose is at the straight tube part in the middle. This structure allows very limited adjustment in the height direction of the connecting hose and demands high precision in cold work welding of the framework for the agent storage cylinder, which is very difficult and takes a lot of work and may lead to poor sealing and excessive vibration of the connecting parts and leak of the agent when it is released. The other kind of high pressure connecting hose has stainless steel joints on both ends with an only short distance between them. The length of the flexible hose can be adjusted freely in both X axis and Y axis directions and the connection is fast and easy with good leak-tight performance. The vibration of the whole gas fire extinguishing system equipment is limited.

(7) A low pressure safety leak valve, or low leakage high sealing vale in another name, has to be installed in the starting pipe of the gas fire extinguishing system with a pipe network to prevent the gas starting device from activating the system by mistake due to slow leakage and effectively guarantee the quality of the product.

3. Good fire extinguishing performance

To judge the fire extinguishing performance of a gas fire extinguishing system (gas fire extinguishing equipment), we have to take into account the quality and sufficiency of the fire extinguishing agent, the leak-tight property and the pressure level of the agent cylinder group and if the system’s design parameters are correct. The key to judge if the fire-extinguishing performance is good or not is if the agent is qualified and if there is no shortage in quantity. Gas suppliers, engineering service providers and the users should perform joint supervision and inspection and take the following measures to ensure the quality of fire extinguishing agents:  

(a) Strict prohibition of the use of unqualified fire extinguishing agents. In the fire extinguishing system, HFC-227ea and ABC superfine dry powder are the two kinds of agents most likely to involve cheating.

Unit price of HFC-227ea fire extinguishing agent varies greatly every year along with changes in the market, mostly between 60~150 yuan/kg, accounting for 50% to 70% of the total manufacturing cost of the whole fire extinguishing system. Main ways to cheat with HFC-227ea agents include: using water or other liquids or solids instead, or using lower purity HFC-227ea agents purchased in the market.

  ABC superfine dry powder fire extinguishing agent is usually replaced with regular BC or regular ABC dry power agents, the unit prices of which can vary by more than four times. Designed fire extinguishing concentration of ABC superfine dry powder agent is 0.13kg/m3, while designed fire extinguishing concentration of regular dry powder is 0.65kg/m3 with a difference of around five times.  

  Measures to take: demanding manufacturers to provide 3C certificates of their products, and making a trip to the manufacturer’s place before it delivers the products and making random sampling of the fire extinguishing agent inside the cylinder groups on the purity and quantity in the presence of the manufacturer.

(b) Prohibition of shortage of quantity of fire extinguishing agent. In the fire extinguishing system, the HFC-227ea agent is usually the one to involve shortage of quantity. Ways of cheating include: (1) filling less-than-stipulated amount of agent into the cylinder, while the weight of the agent provided on the product plate is larger than the actual weight of the agent filled into the cylinder; (2) adding more nitrogen gas, the propellant to replace part of the weight of HFC-227ea.

The total weight of an HFC-227ea fire extinguishing agent storage cylinder consists three parts: 1. the weight of the empty cylinder and the parts W1, including the valve, the siphon and the steel cylinder; 2. the weight of the HFC-227ea fire extinguishing agent filled into the cylinder W2. The weight of fire extinguishing agent of a cylinder group is determined by the natural of the protected object, the size of the protected space and the total number of cylinder groups of the system; 3. the weight of nitrogen gas, the propellant gas for HFC-227ea agent W3, the calculation formula is: W=W1+W2+W3. The cabinet HFC-227ea gas extinguishing device is also called HFC-227ea pre-engineered extinguishing system, the nitrogen gas in which is normally 1% to 3.7% of the total weight of the HFC-227ea filled in the cylinder group, while in an HFC-227ea gas extinguishing system with pipe networks, nitrogen is usually 4.4% to 7.1% of the total weight of HFC-227ea filled in the cylinder group.

The often-used 40, 70, 90, 120 and 150-liter empty cylinders in cabinet HFC-227ea gas extinguishing devices weigh around 44, 59, 71, 87 and 112 kilograms respectively. The often-used 70, 90, 120 and 150-liter empty cylinders in HFC-227ea gas extinguishing equipment with pipe network weigh around 68, 81, 100, and 120 kilograms respectively. We provide the weights of the empty HFC-227ea fire extinguishing agent cylinders for the purpose of providing reference for engineering service providers, users, supervisors and inspection and accepting units in their weighing and checking.  

Measures to take: before the manufacturer delivers the products, go to the location of the manufacturer, or to the cylinder group room at project’s installation site and make random sampling of one to three fire extinguishing agent cylinder groups and check their total weights; check if the cylinder groups are stilled perfectly sealed with no sign of any leaking; if the total weight of a fire extinguishing agent cylinder group is below standard, it means the gas manufacturer has failed to fill enough gas into the cylinder, or the dealer (or engineering service provider) has changed the weight provided on the product plate, and not because there is leakage of the agent. Based on the result of the random sampling of fire extinguishing agent cylinder groups, list the weights of the empty cylinders (vs the weights provided by the manufacturer and the weight provided above), the weights of fire extinguishing agents (vs the weights provided on the drawings made by the design institute, the weights of propellant nitrogen gas, calculate based on the above information and find out the actual weight of HFC-227ea fire extinguishing agent fill into the cylinder group.  

For example: sample-checking one of the cylinders of an 150-liter-cylinder group of a HFC-227ea gas extinguishing system with pipe network to find out the actual weight of HFC-227ea filled into this cylinder group.

 The following are the checks and calculations:

(1) Check the sealing property of the 150-liter-cylinder group and make sure there is no leaking;

(2) Weigh the 150-liter-cylinder group, and if W=256.6Kg,

(3) Check if the weight provided on the product plate of the cylinder group is the same as the one designated by the design institute;

(4) Check the plate on the cylinder group to see if the weight of HFC-227ea filled into the cylinder is 122kg and the total weight of the cylinder group is 256.5kg;  

(5) The calculation of the weight of the HFC-227ea agent filled in the cylinder should be based on the weight of the 150-liter empty cylinder provided by the manufacturer, or in reference to the weight of the 150-liter empty cylinder provided above: W1=128.6kg; the weight of the agent W2 =256.6-128.6=128kg, while the weight of nitrogen gas W3=256.6-128.6-122=6kg, and nitrogen gas account for (6/122×100%=) 4.9% of the weight of HFC-227ea, which conforms to the required rate provided above. The actual weight of HFC-227ea fire extinguishing agent filled in the cylinder is 122 kg, conforming to the required standard.

4. Vibration and high/low temperature resistance

All parts and components of the products for the gas fire extinguishing system product “Belt and Road” exporting project (also called gas fire extinguishing system exporting project, or gas fire extinguishing system exporting or gas fire extinguishing equipment exporting for short) should have good vibration resistance and high and low temperature resistance, can tolerance the long-distance trek of the three-dimensional transportation of sea, land and air and will not cause leakage or mis-initiation of equipment due to wind, waves, bumps, high and low temperature meteorological conditions during transportation. All parts and components of the products for the gas fire extinguishing system product “Belt and Road” exporting project (also called gas fire extinguishing system exporting project, or gas fire extinguishing system exporting for short) should be designed to resist vibrations, particularly the valves of the agent cylinder groups should adopt the double sealing horizontal pressure-gradient structure that has two air chambers, and a piston disc is installed inside the valve body that seals automatically thanks to the air pressure inside the valve body. A special starting cylinder and an ejector pin have to be installed to pierce the diaphragm seal of the air chamber of the cylinder valve in order to open the cylinder valve of the cylinder group. The valve does not have any opening handle or other prats. The most important feature of this kind of cylinder valve is that it is collision and vibration resistant and can withstand temperatures as high as +70℃ and as low as -30℃. This can ensure that vibrations and temperature changes will not lead to the leakage of fire extinguishing agent and the cylinder can not be accidentally activated.

5. Packaging

The gas fire extinguishing system product “Belt and Road” exporting project (also called the gas fire extinguishing system exporting project, or gas fire extinguishing system exporting or gas fire extinguishing equipment exporting for short) has strict requirement on the packaging of the products. All parts and components of gas fire extinguishing systems have to be packaged in boxes, and the packaging has to comfort to the following:

(1) Export packing boxes, also called export wooden packing boxes, export wooden boxes, plywood boxes, fumigation-free packaging boxes should be used for packaging, and it is absolutely prohibited to use the ordinary wooden packaging boxes, or the products will not be cleared by the customs.  

(2) The shipping mark on the packing boxes must include the following information:

① Abbreviated or short form of the name of the consignee or buyer;           

② Reference Number, e.g. waybill number, order number or invoice number;  

③ Place of destination:  

④ Number of packages.

(3) Packing boxes must undergo damp-proof treatment by applying moisture-proof films on the inner walls of the boxes and placing certain quantity of desiccant inside.  

（4）Packing boxes must undergo shock-proof treatment by applying shock-absorbing foamed plastic boards on the internal walls of the boxes, and all parts and components inside the boxes must be placed orderly, separated from each other with foamed plastic boards and make sure all empty spaces are filled with foamed plastics. Each agent cylinder group must be fixed at the bottom of the packing boxes with two to three packing straps to prevent it from rolling or bumping during shipping.

(5)A packing list should be placed inside each boxes, with information including names of the parts and components inside the box, and their models, specifications and numbers, etc.  

(6) There must be a pallet below each packing box for the convenience of loading and transshipping.

(7) Steel pipes and other overlength parts that can not be packed inside the boxes can be packed by stacking orderly and regularly on a pallet for the convenience of transporting with forklifts and other vehicles. The stacks must be strapped and fixed with steel bands every two meters or so to prevent the steel pipe stacks from getting loose and collapse.

6. Easy and speedy installation with no need for on-the-spot processing

As the products involved in the gas fire extinguishing system product “Belt and Road” exporting project (also called gas fire extinguishing system exporting project, or gas fire extinguishing system exporting, or gas fire extinguishing equipment exporting for short) are to be installed abroad, where conditions mostly do not allow to perform on-the-spot processing, it is required that all the parts and components should finish processing before being delivered and it is not allowed to conduct secondary processing on the installation site. It is advised to make the starting pipes between the starting devices and the cylinder groups of the fire extinguishing systems with the relatively costly stainless steel flexible metal pipes instead of the lower-cost DN4~6mm copper pipes that are used now by most domestic manufacturers in China, because if DN4~6mm copper pipes are used, we have to tailor, cut, bend and enlarge the opening of the copper pipes on-site using special tools and according to the actual conditions before being able to start the pipes. The on-site installation technical workers also need special training and practices before being able the do the work. If we replace the DN4~6mm copper pipes with stainless steel metal pipes, no on-site processing will be needed anymore. (So far, Beijing Leader Haixin is the only company in China to apply this method and “Customer Centricity” is the principle of this company). Although it increases some cost for the manufacturer, it avoids the hassle of on-site processing if copper pipes are used and realizes zero on-the-spot processing for the system, lowering the professional and technical demand for the installation workers and making the installation simpler, faster and more convenient, raising the installation efficiency by more than four times, greatly reducing the installation cost and ensuring more reliable sealing performance of the starting pipes of the fire extinguishing system.  

7. Installation can be performed according to provided materials and drawings without the need for on-site instruction by technicians sent by the manufacturer

As the installations of the gas fire extinguishing system product “Belt and Road exporting project (also called gas fire extinguishing system exporting project, or gas fire extinguishing system exporting, or gas fire extinguishing equipment exporting for short) are made in foreign countries, it is better that installations can be done according to the provided materials and drawings, without the need of on-site instructions by technicians sent by the manufacturer to save the time for installation and costs of sending people abroad. The gas fire extinguishing system product exporting project (also called the gas fire extinguishing system exporting project, or gas fire extinguishing system exporting or gas fire extinguishing equipment exporting for short) should prepare detailed system installation and cylinder group room equipment installation drawings for each and every project. It is advised to perform actual installation of the cylinder group room equipment inside the manufacturing plant before delivering the products, video-record and take photos of the installation process and make special slides according to the order of the installation. These documents and drawings will be provided to the users along with the products, and make sure that users can assemble the parts and components of the fire extinguishing system very easily like children build blocks according to drawings, and the manufacturer will not need to send technicians to provide on-site instructions. If there is still any problem, they can communicate with the manufacturer through WeChat, real-time video and telephone conversation to solve the difficulties.   

8. Responsibilities of the dealers

With the above, we have elaborated to the manufacturers the main technical requirements and measures to ensure safety, sealing and fire extinguishing performance of the gas fire extinguishing system product “Belt and Road” projects. Cheating in the quality and quantity of gas fire extinguishing system products and fire extinguishing agents can be the behavior of the manufacturers. Sometimes, it is done under the requirement of the dealers (engineering service providers). On other occasions, it is done independently by the dealers (engineering service providers). We urge that all parties must discipline themselves and users and dealers should choose brand name products from manufacturers with good reputations. We hope that the Changchun Changsheng vaccine incident never happens to gas fire extinguishing product manufacturers and dealers (engineering service providers), or in the fire protection sector. Hereinafter, I would like to elaborate on the responsibilities of the dealers. Currently, there are still some dealers and engineering service providers who know that some producers or manufacturers are producing unqualified products that threaten the personal and property safety of the people, yet they still continue to use those substandard products, thinking that even if any accident happens, the responsibilities are all on the producers or manufacturers that have legitimate production permits. According to the relevant laws and regulations of China and the relevant provisions in Chapter 3 Operator's Obligations of the Law of the People's Republic of China on the Protection of Consumer Rights and Interests, the operator shall ensure that the goods or services provided are in compliance with the requirements for the protection of personal and property safety. If it is found that the goods or services provided are defective, and there is a danger to personal or property safety, it shall immediately report to the relevant administrative department, stop selling, recall, and bear the necessary expenses arising from the product recall for the user or consumer. If any loss incurred by purchasing the illegal product from the operators by the user or the consumer, the operator may be required to pay compensation.

To ensure the personal and property safety of the people, users, dealers (engineering service providers) and production enterprises all have obligations to abide by the laws, do not use unqualified products or perform cheating, and do their respective contributions to protect the personal and property safety of the users or consumers, maintain social and economic order, and promote the healthy development of the market economy.

Finished on: July 28, 2018; Revised on: Aug. 5, 2018

Author’s address: Beijing Leader Haixin Company, 17 Rongjing Dongjie, Beijing Economic and Technological Development Area, Beijing

Postcode: 100176    Tel: 13910793712

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