Conventional sprinkler joints have more than 6 spots of jointing with the risk of water leakage as their elbow and reducer are assembled and connected after screw processing is done on the tips of the both sides of a steel pipe. It is quite hard to adjust location of the sprinkler head up or down or right or left. Also, installation of the equipment on the narrow ceiling requires high-skilled construction workers and long time due to the obstacles of the structure such as air-cooling, heating ducts, electricity and communications facilities.
Sprinkler flexible joints supplied by Dong-A has obtained quality certification from UL, FM(USA), VdS(Germany), FESC(Japan) and KFI(Korea), and are used for high pressure as their nipples, reducer, and stainless steel flexible tubes are all combined in one body. With only two joint points, the risk of water leakage has greatly reduced. And as it is flexible, even unskilled workers will find it easy to work with the tubes. It can cut down installation costs dramatically with the time spent for the construction greatly reduced by more than 20 times than that of steel pipe type. With the quality certificate obtained in U.S.A., Britain, Germany, and Japan, the high quality of this sprinkler system has been widely proven.
Non Braided type
As Dong-A’s stainless steel flexible joint has width of the weld bead with less than 0.7㎜, thickness of the weld bead part is the same as that of the parent material. Also, as corrugation is formed after heat-treatment of the welding part (bead part and welding heat affected part), the Slip band Martensite is minimized. The best corrugated tubes have been used with standardized heat treatment based on the advanced technology.
If the corrugated tube and fitting (reducer or nipples) are connected with the screw, stray current corrosion due to the electric potential difference is prevented and the tube is protected against the electric spark during the work. As length of the nut is a limit screw(10.5㎜ length), and the rectangle packing and the 45 degree angle slope surface are sealed tightly, even unskilled workers will find it easy to work with the tubes. If the tubes are connected by welding(SPN, SPNB, SPW, SPWB), as heat treatment for the flexible tube in the solution treatment furnace is done simultaneously while conducting welding thus has increased its anticorrosiveness without any welding tension caused by the welding heat.
20 kinds of brackets suitable for the sealing board bar(bar & grid) which is installed in a structure have been developed and supplied in a set. And a set of sprinkler flexible joint for an apartment is also provided.
* The sprinkler drop system SP model for fire-fighting purpose : As a corrugated tube in helical type, a reducer and a nipple on the ends of each side of the tube are assembled in a screw connection approach.
* The sprinkler drop system SPN model for fire-fighting purpose : As a corrugated tube in helical type, a stainless steel reducer at the one end of the tube is welded while a nipple at the other end is connected in a screw connection approach.
* The sprinkler drop system SPW model for fire-fighting purpose : As a corrugated tube in helical type, a stainless steel reducer and a stainless steel nipple on the ends of each side of the tube are connected with the tube by welding. This model is made of stainless
steel and used for clean rooms as well.
* For high pressure application : Model SPB, SPNB, SPWB
(which are covered with stainless steel braid on the flexible tube of SP, SPN, SPW as both ends welded) are for high pressure application and obtained quality certification from FM(USA) and Vds(Germany).
· Common Point
– working pressure: (12.3kgf/cm²), 175psi
– Maximum temperature: 225 °F (107.2℃ ~ 163℃)
– Material: stainless steel AISI 316L/304
– Thickness of tube: 0.3mm / 0.4mm
– Length of tube: Dong-a spec. / according to customer’s demand
– Minimum bend radius: 75㎜ ~ 153㎜
· It varies depending on the certificate authority
· Device to fix on Structure
A perfect fixing device, brackets and square bars whose stability and quality were proven from LPCB(UK), UL(USA) and FM(USA) and VdS(Gemany) and also USA patent are supplied in a set.