MICROFAST
®
QUICK
RESPONSE FUSIBLE
ELEMENT CONVENTIONAL
SPRINKLER VK311 (K5.6)
TECHNICAL DATA
Page 1 of 3
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: techsvcs@vikingcorp.com
Visit the Viking website for the latest edition of this technical data page www.vikinggroupinc.com.
Form No. F_022614 18.11.05 Rev 17.1.P65
1. DESCRIPTION
The Viking Microfast
®
Quick Response Fusible Element Conventional Sprinkler VK311 is a small,
thermosensitive, solder link spray sprinkler available in several different finishes, and tempera-
ture ratings to meet design requirements. The special Polyester coatings can be used in decora-
tive applications where colors are desired.
2. LISTINGS AND APPROVALS
cULus Listed:
Category VNIV
Refer to Approval Chart 1 and Design Criteria on for cULus Listing requirements.
3. TECHNICAL DATA
Specifications:
Minimum Operating Pressure: 7 psi (0.5 bar)
Maximum Working Pressure: 175 psi (12 bar)
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: 5.6 U.S. (80.6 metric*)
Overall Length: 2-3/16” (56 mm)
* Metric K-factor measurment shown is in Bar. When pressure is measured in kPa, divide the metric K-factor shown by 10.0.
Material Standards:
Frame Casting: Brass UNS-C84400 or QM Brass
Deflector: Brass UNS-C26000
Fusible Element Assembly: Nickel Alloy
Trigger and Support: Stainless Steel UNS-S31600
Belleville Spring Sealing Assembly: Nickel Alloy, coated on both sides with PTFE Tape
Seat and Insert Assembly: Copper UNS-C11000 and Stainless Steel UNS-S30400
Screw: Brass UNS-C36000
For Polyester Coated Sprinklers:
Belleville Spring-Exposed
Ordering Information:
(Also refer to the current Viking price list.)
Order Quick Response Fusible Element Conventional Sprinklers by first adding the appropriate suffix for the sprinkler finish and
then the appropriate suffix for the temperature rating to the sprinkler base part number.
Finish Suffix: Brass = A, Chrome = F, White Polyester = M-/W, and Black Polyester = M-/B
Temperature Suffix (°F/°C): 165°/74° = C, 205°/96° = E, and 280°/138° = G
For example, sprinkler VK311 with a Brass finish and a 165 °F/74 °C temperature rating = Part No. 19392AC
Available Finishes And Temperature Ratings:
Refer to Table 1
Accessories:
(Also refer to the Viking website.)
Sprinkler Wrenches:
Standard 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.
Replaces form F_071614 Rev. 17.1
(Added P65 Warning.)
