Introducing water mist know-how – Part 2

Water mist know-how is still a comparatively new idea in terms of fireplace suppression, yet it is proving to be an exciting growth within the industry. As the industry evolves, so do the laws, laws and necessities to find a way to improve security and allow improvement. These can differ largely from country to nation, and even region to area.
The method in which a water mist system operates is an analogous mechanism to the standard sprinkler system in that the nozzles are usually activated via a bulb which blows at a selected temperature permitting for the activation of the mist through a low-pressure water piping system.
Here we take a look at how some water mist nozzles are produced and put in – from arriving as a large ‘bar’ of metallic, to turning into the environment friendly water mist nozzles we see put in in many new projects/developments throughout much of the globe at present.
The metal arrives for cutting
Here at Dual Mist Ltd, Stainless Steel 304 is used for lots of components as this can be very sturdy and corrosion resistant compared to other similar metals. The physique is machined out of Brass CZ121, which arrives as large bars of metal which might be delivered to the warehouse in 3m lengths. This is then cut into two smaller components ready to insert into the machine. Not all water mist companies have the power to machine the components they require in-house though it could show very helpful for price and production functions as we’re about to see.
The metal is fed to a Nakamura WT150 CNC lathe. This high-performance Japanese machine software is equipped with carbide tooling and high-pressure by way of coolant techniques, with the twin-spindle and twin-turret making haste of the in any other case complicated components. A Citizen M532 Sliding Head Lathe is used for the smaller elements.
A Citizen L12 also makes the filters with a functionality of drilling 365 holes in 51 seconds, completely automated – this implies it can turnover an unbelievable 4,000 filters in a weekend fully unmanned.
The brass heads are also de-burred on the machine, eradicating all sharp edges earlier than being polished and despatched for Electroless Nickel Plating. This provides a corrosion-proof coating to the brass, enabling it to become far more durable. All parts are then inspected for dimensional accuracy earlier than the meeting stage.
This Technifor Laser machine engraves every nozzle in preparation for the testing stages.
There are many small components of assorted sizes and shapes that make up the nozzle – In the DM4R nozzle, (as seen on the leak-testing pic) there are a complete of thirteen components or ‘components’. These elements are then meticulously put collectively and assembled by the manufacturing team requiring a good quantity of labour earlier than the final product is achieved. Various phases embrace tightening with specially adapted tools, pressing using a hand-press and utilizing a particular ‘Locktite’ method at some phases which is a threadlock that prevents fixings from coming free in the course of the operational lifetime of the product. The ultimate stage of assembly is rigorously loading the bulb and applying the proper load to it utilizing a torque wrench.
The assembled nozzles are then placed on one other machine in order to be labelled and uniquely recognized utilizing a serial number. At Dual Mist Ltd that is done on a Technifor Laser Engraver fitted with a 4th axis unit before they are able to be positioned by way of the assorted phases of testing.
Cull Testing
Also often identified as bubble testing in layman’s terms, this take a look at is to make sure no harm has occurred to the bulb during assembly and is a crucial take a look at for LPCB approval. The test entails utilizing a high-powered microscope to measure the dimensions of the bubble in every bulb before placing in heat water so as to shrink the size of the bubble to nothing. Once that is checked, the nozzles are then left to rest and return to room temperature earlier than the bubble is measured as soon as again to have the ability to ensure it has returned to the original size within a small tolerance.
Leak Testing
Every nozzle can be stringently tested for leaks by applying 24-bar strain for 1 hour and ensuring no water has escaped. It is uncommon for any leaks on the manufacturing line, but this is a particularly vital stage of the testing as leaks could occur if dust is trapped within the seal face.
Activation Testing
On a month-to-month basis, random nozzles are additionally tested for activation by putting the nozzle on a stress jig at varied pressures and applying warmth to the bulbs. The nozzles should all activate cleanly across the entire pressure vary specified to that nozzle.
A member of the production team uses a microscope and software program to find out the scale of every bubble within the bulb.
At Dual Mist Ltd, these tests usually are not just to guarantee the standard of the manufacturing line but are also an important part of the LPCB Approval. These approvals enable prospects to recognise that the merchandise they are shopping for are made to the best potential high quality standard in the region.
The drawback to that is that the Approval Testing system may be both pricey and time-consuming – sometimes needing to be booked several months upfront and requiring years of hard work to realize.
The nozzles produced by Dual Mist have been put through their paces at BRE Global when it comes to each hearth testing and component/type approval.
Tamper proofing
In order to guarantee that no one is tempted to intervene with the grub screw holding the bulb, a small plastic bung is pressed into the grub screw. The strain load setting on the bulb is then subsequently fixed.
The nozzles are then able to be packaged and despatched off for installation.
Here is เกจวัดแรงดันสูญญากาศ 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 metal pipes typically used in high-pressure techniques, low-pressure water techniques can use CPVC piping. This is a special type of fire-resistant plastic enabling quick installation. Instead of threading each pipe, a heated glue can be used to rapidly build large pipe networks. These networks are permitted to deal with as much as 12 bar strain. The nozzles are screwed right into a special pipe adaptor using a half-inch fuel becoming.
An electric management panel is fitted for the system management together with pumps and a water tank, normally with a mains feed.
The system is tested, signed off and handed over to the consumer.
The last product as quickly as installed. This reveals how we anticipate to see the nozzles as quickly as a challenge has been completed.
As we will see there are many levels to go from metallic to nozzle head with every nozzle taking a major effort by various professionals to finish to the accredited standard.
Not solely do water mist nozzles require a number of stages of machining and assembling, they have to also endure a string of tests to have the ability to be approved for installation. Once put in, there are even further exams undergone, typically by third-party organisations in order for the entire fireplace suppression system to lastly be handed over to the consumer.
Water mist know-how assures safety, high quality and assurance through the stringent testing that’s required.
With the recent publication of water mist requirements, particularly in Britain over current years, building builders can now be assured that the quality required for water mist methods is now at an equivalent commonplace to other suppression techniques.
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