TECHNICAL DATA
QREC CONCEALED HSW
SPRINKLER VK638-D (K8.0)
Page 1 of 7
Form No. F_082211 19.09.23 Rev 19.1
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 Quick Response Extended Coverage Concealed Horizontal Sidewall Sprinkler
VK638 is a thermosensitive spray sprinkler pre-assembled with a threaded adapter
for installation with a domed cover. The glass bulb operating element and special
deflector characteristics meet the challenges of quick response extended coverage
standards.
The cover plate provides up to 1/4” (6.35 mm) of horizontal adjustment and is avail-
able with several decorative finishes to meet design requirements. The two-piece
design allows installation and testing of the sprinkler prior to installation of the cover
plate. The “push-on”, “thread-off” design of the concealed cover plate assembly
allows easy installation of the cover plate after the system has been tested and the
finish work has been completed. The cover assembly can be removed and reinstalled,
allowing access behind the surface of the wall without taking the sprinkler system out
of service or removing the sprinkler.
The Electroless Nickel PTFE (ENT) coating has been investigated for installation in
corrosive environments and is listed and approved as indicated in the Approval Charts.
The ENT finish is only available for the sprinkler assembly, the cover plate is not plated.
2. LISTINGS AND APPROVALS
cULus Listed:
Category VNIV
Refer to the Approval Chart and Design Criteria for cULus Listing require-
ments that must be followed.
3. TECHNICAL DATA
Specifications:
Available since 2012.
Maximum Working Pressure: 175 psi (12 bar)
Factory tested hydrostatically to 500 psi (34.5 bar).
Thread size: 3/4” (20 mm) NPT
Nominal K-Factor: 8.0 U.S. (115.2 metric
†
)
†Metric K-factor measurement is in Bar. When pressure is measured in kPa, divide the metric K-factor shown by 10.0.
Glass-bulb fluid temperature rated to -65 °F (-55 °C)
Overall Length (Sprinkler Body): 2-3/4” (70 mm)
Covered by the following US Patent Nos: 7,854,269; 7,712,218; and 8,662,190
Material Standards:
Sprinkler Frame: Brass UNS-C84400
Flow Shaper: Brass UNS-C23000
Bulb: Glass, nominal 3 mm diameter
Pip Cap and Insert Assembly: Copper UNS-C11000 and Stainless Steel UNS-S30400
Compression Screws: 18-8 Stainless Steel
Belleville Spring Sealing Assembly: Nickel Alloy, coated on both sides with Polytetrafluoroethylene (PTFE) Tape
Yoke: Phosphor Bronze UNS-C51000
Cover Adapter: Cold Rolled Steel UNS-G10080, Finish: Clear Chromate over Zinc Plating
Cover Assembly Materials:
Cover: Copper UNS-C11000
Base: Brass UNS-C26800
Springs: Nickel Alloy
Solder: Eutectic
Ordering Information:
(Also refer to the current Viking price list.)
Viking QREC Concealed HSW Sprinkler VK638-D and Cover Plate Assembly must be ordered separately:
Sprinkler:
Base Part No. 17375A-X for standard brass and 17375JN-X for ENT** - insert the desired temperature rating suffix where
the dash (-) is located (includes sprinkler and adapter pre-assembled, with a protective plastic cap covering the unit).
Specify sprinkler temperature rating by adding the appropriate suffix for the temperature rating to the base part number:
Temperature Suffixes: 135 °F (57 °C) = A, 155 °F (68 °C) = B, 175 °F (79 °C) = D, 200 °F (93 °C) = E
For example, sprinkler VK638 with a 175 °F (79 °C) temperature rating = 17375ADX.
**ENT is not available in 135 °F (57 °C).
SPECIAL FEATURES:
•
For Light Hazard Occupancies Only
•
Designed for Corridor Applications
•
28’ Maximum Width Spacing
Replaces Form No. F_082211 Rev 14.1.P65
(Added ENT.)
