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MICROFAST
®
QUICK
RESPONSE VERTICAL
SIDEWALL SPRINKLER
VK337 (K4.2)
TECHNICAL DATA
Page 1 of 3
Form No. F_050300 18.11.05 Rev 17.1.P65
The Viking Corporation, 210 N Industrial Park Drive, Hastings MI 49058
Telephone: 269-945-9501 Technical Services: 877-384-5464 Fax: 269-818-1680 Email: [email protected]
Visit the Viking website for the latest edition of this technical data page www.vikinggroupinc.com.
1. DESCRIPTION
Viking Microfast
®
Quick Response Vertical Sidewall Sprinkler VK337 is a small thermo-
sensitive glass bulb spray sprinkler designed for installation in either the upright or pen-
dent position. VK337 is available with temperature ratings to meet design requirements.
2. LISTINGS AND APPROVALS
3. TECHNICAL DATA
Specifications:
Minimum Operating Pressure: 7 psi (0.5 bar)
Rated to 175 psi (12 bar) water working pressure.
Factory tested hydrostatically to 500 psi (34.5 bar)
Testing: U.S.A. Patent No. 4,831,870
Thread size: Refer to the Approval Chart
Nominal K-Factor: 4.2 U.S. (57 metric*)
Glass-bulb fluid temperature rated to -65 °F (-55 °C)
Overall Length: 2-1/4” (58 mm)
Material Standards:
Frame Casting: Brass UNS-C84400
Deflector: Brass UNS-C23000
Bulb: Glass, nominal 3 mm diameter
Belleville Spring Sealing Assembly: Nickel Alloy, coated on both sides with PTFE Tape
Screw: Brass UNS-C36000
Pip Cap and Insert Assembly: Copper UNS-C11000 and Stainless Steel UNS-S30400
Ordering Information:
(Also refer to the current Viking price list.)
Order Quick Response Vertical Sidewall Sprinklers by first adding the appropriate suffix for the sprinkler finish and then the ap-
propriate suffix for the temperature rating to the sprinkler base part number.
Finish Suffix: Chrome = F
Temperature Suffix (°F/°C): 155°/68° = B, 175°/79° = D, 200°/93° = E, 286°/141° = G
For example, sprinkler VK337 with a Chrome finish and a 155 °F/68 °C temperature rating = Part No. 08985FB
Available Finishes And Temperature Ratings:
Refer to Table 1
Accessories:
(Also refer to theViking website.)
Sprinkler Wrench:
Part No. 21475M/B (available since 2017).
Sprinkler Cabinets:
A. Six-head capacity: Part No. 01724A (available since 1971)
B. Twelve-head capacity: Part No. 01725A (available since 1971)
4. INSTALLATION
Refer to appropriate NFPA Installation Standards.
5. OPERATION
During fire conditions, the heat-sensitive liquid in the glass bulb expands, causing the glass to shatter, releasing the pip cap and
sealing spring assembly. Water flowing through the sprinkler orifice strikes the sprinkler deflector, forming a uniform spray pattern
to extinguish or control the fire.
6. INSPECTIONS, TESTS AND MAINTENANCE
Refer to NFPA 25 for Inspection, Testing and Maintenance requirements.
7. AVAILABILITY
Viking Quick Response Vertical Sidewall Sprinklers are available through a network of domestic and international distributors. See
The Viking Corporation web site for the closest distributor or contact The Viking Corporation.
8. GUARANTEE
For details of warranty, refer to Viking’s current list price schedule or contact Viking directly.
Replaces Form No. F_050300 Rev 17.1
(Added P65 Warning.)