Introducing water mist technology – Part 2

Water mist know-how continues to be a comparatively new idea in terms of hearth suppression, but it is proving to be an exciting growth in the industry. As the industry evolves, so do the regulations, legal guidelines and requirements in order to improve security and allow improvement. These can differ largely from nation to country, and even region to region.
The method in which a water mist system operates is a similar mechanism to the standard sprinkler system in that the nozzles are often activated via a bulb which blows at a specific temperature allowing for the activation of the mist via a low-pressure water piping system.
Here we have a look at how some water mist nozzles are produced and installed – from arriving as a large ‘bar’ of metallic, to turning into the environment friendly water mist nozzles we see put in in lots of new projects/developments throughout a lot of the globe at present.
The steel arrives for cutting
Here at Dual Mist Ltd, Stainless Steel 304 is used for so much of elements as it is extremely durable and corrosion resistant compared to other related metals. The body is machined out of Brass CZ121, which arrives as large bars of metallic that are delivered to the warehouse in 3m lengths. This is then cut into two smaller components able to insert into the machine. Not all water mist corporations have the ability to machine the parts they require in-house though it could show very beneficial for value and production purposes as we’re about to see.
The metal is fed to a Nakamura WT150 CNC lathe. This high-performance Japanese machine software is supplied with carbide tooling and high-pressure by way of coolant techniques, with the twin-spindle and twin-turret making haste of the otherwise difficult elements. A Citizen M532 Sliding Head Lathe is used for the smaller elements.
A Citizen L12 also makes the filters with a capability of drilling 365 holes in fifty one seconds, fully automated – this means it could turnover an unimaginable four,000 filters in a weekend completely unmanned.
The brass heads are additionally de-burred on the machine, removing all sharp edges earlier than being polished and sent for Electroless Nickel Plating. This supplies a corrosion-proof coating to the brass, enabling it to turn out to be far more durable. All components are then inspected for dimensional accuracy before the assembly stage.
This Technifor Laser machine engraves each nozzle in preparation for the testing stages.
There are many small parts of varied styles and sizes that make up the nozzle – In the DM4R nozzle, (as seen on the leak-testing pic) there are a complete of 13 parts or ‘components’. These parts are then meticulously put together and assembled by the production team requiring a good amount of labour earlier than the ultimate product is achieved. Various levels include tightening with specially adapted instruments, pressing using a hand-press and utilizing a selected ‘Locktite’ formula at some levels which is a threadlock that prevents fixings from coming unfastened during the operational lifetime of the product. The final stage of assembly is carefully loading the bulb and applying the proper load to it using a torque wrench.
The assembled nozzles are then positioned on one other machine in order to be labelled and uniquely recognized using a serial quantity. At Dual Mist Ltd this is done on a Technifor Laser Engraver fitted with a 4th axis unit before they are able to be placed by way of the varied phases of testing.
Cull Testing
Also known as bubble testing in layman’s terms, this take a look at is to ensure no injury has occurred to the bulb throughout meeting and is a critical test for LPCB approval. The test includes utilizing a high-powered microscope to measure the scale of the bubble in each bulb earlier than placing in heat water to find a way to shrink the scale of the bubble to nothing. Once that is checked, the nozzles are then left to rest and return to room temperature before the bubble is measured as quickly as again in order to guarantee it has returned to the original measurement inside a small tolerance.
Leak Testing
Every nozzle can be stringently tested for leaks by applying 24-bar stress for 1 hour and guaranteeing no water has escaped. It is rare for any leaks on the manufacturing line, but this is an especially vital stage of the testing as leaks could occur if dust is trapped throughout the seal face.
Activation Testing
On a monthly basis, random nozzles are also examined for activation by putting the nozzle on a strain jig at varied pressures and making use of heat to the bulbs. The nozzles ought to all activate cleanly throughout the whole strain vary specified to that nozzle.
เกจ์วัดแรงดันน้ำมันเครื่อง of the manufacturing staff makes use of a microscope and software program to determine the size of each bubble in the bulb.
At Dual Mist Ltd, these tests are not simply to guarantee the standard of the manufacturing line however are also an essential a part of the LPCB Approval. These approvals enable clients to recognise that the merchandise they are shopping for are made to the best potential quality normal in the area.
The disadvantage to this is that the Approval Testing system can be each costly and time-consuming – typically needing to be booked several months in advance and requiring years of hard work to achieve.
The nozzles produced by Dual Mist have been put through their paces at BRE Global when it comes to both hearth testing and component/type approval.
Tamper proofing
In order to ensure that no person is tempted to intervene with the grub screw holding the bulb, a small plastic bung is pressed into the grub screw. The pressure load setting on the bulb is then subsequently fastened.
The nozzles are then able to be packaged and despatched off for set up.
Here is an example of a management panel having been put in in The Claridges Hotel, London, UK. This is the place the system is operated.
Rather than having to use the heavy and labour-intensive metallic pipes often used in high-pressure methods, low-pressure water techniques can use CPVC piping. This is a special type of fire-resistant plastic enabling fast installation. Instead of threading every pipe, a heated glue can be utilized to quickly build giant pipe networks. These networks are approved to deal with as a lot as 12 bar stress. The nozzles are screwed right into a particular pipe adaptor utilizing a half-inch fuel fitting.
An electrical management panel is fitted for the system management together with pumps and a water tank, often with a mains feed.
The system is tested, signed off and handed over to the consumer.
The final product as soon as put in. This shows how we expect to see the nozzles as soon as a challenge has been completed.
As we are able to see there are tons of stages to go from steel to nozzle head with every nozzle taking a big effort by varied professionals to complete to the accredited commonplace.
Not solely do water mist nozzles require a number of phases of machining and assembling, they need to also endure a string of tests so as to be accredited for set up. Once installed, there are even additional exams undergone, typically by third-party organisations to guarantee that the whole hearth suppression system to finally be handed over to the client.
Water mist know-how assures safety, quality and assurance through the stringent testing that’s required.
With the current publication of water mist standards, significantly in Britain over current years, constructing builders can now be assured that the quality required for water mist techniques is now at an equivalent standard to other suppression methods.
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