NIBCO Technical Services • Phone: 1.888.446.4226 • Fax: 1.888.336.4226
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I.
SHIPMENT & STORAGE
NIBCO butterfly valves are individually boxed thru the 12" size. The 14" through 60" butterfly
valves are shipped individually with the faces covered using cardboard or plywood to protect the
flange sealing surfaces.
The disc is shipped in the nearly closed position to protect the sealing edge and prevents the
liner from taking a temporary set. The stem bushings and disc edge have been coated with a
factory-applied lubricant to prolong storage and service life.
Valves may be shipped or stored in any position. Storage should be limited to 10 years indoors
with a temperature range of 40º F to 90º F (4°C to 32°C).
II.
BUTTERFLY VALVE INSTALLATION GUIDELINES
NIBCO rubber-lined butterfly valves, depending on size and pressure rating, are designed to
mate with Class 125/150 flange patterns in conformance to ASME B16.1, ASME B16.5, or
ASME B16.47 (Series A) flanges. Cast iron and steel flat-face flanges can be used with all
NIBCO butterfly valves; however, steel raised-face flanges should not be used with cast grey
iron lug-style butterfly valves (NIBCO LC2000 and N200 series).
While flange standards specify flange OD, thickness, bolt size, bolt-circle diameter, and number
of bolts, they may not specify flange opening ID. Care must be used when selecting mating
components for use with NIBCO lug and wafer style butterfly valves.
The internal diameter of
flanges, fittings, and pipe must be compatible with the butterfly valve for proper seal-face
integrity and disc operation
.
When in the open position, the disc extends outward from the valve body. The internal diameter
of connecting components must be large enough to allow clearance for the disc to fully open.
The disc clearances specified in Table 1 (below) are in accordance with
MSS Standard Practice
SP-67 Butterfly Valves
,
Table A1
.
NIBCO 2” thru 48” size butterfly valves have an integral rubber face that seals to the attaching
flange; therefore, a separate gasket is not necessary and should never be used.
The flange inside diameter must not be too large or it will not mate properly with this integral
seal. See Table 1 (below) for minimum and maximum inside diameters of connecting
piping/flanges to assure proper seal-face integrity and full operation of NIBCO butterfly valves.
Verify the inside diameter and clearance dimensions of all components connecting directly to a
butterfly valve
.
NIBCO butterfly valves are bi-directional and may be installed with flow in either direction. These
valve can be installed in any horizontal or vertical position. If a choice of stem positions exists,
the valve should be installed with the stem in the horizontal position; this will minimize seat wear
by distributing the stem and disc weight evenly. Also, if the media is abrasive, the horizontal
stem position is highly preferred.
Butterfly valves should be installed a minimum of six (6) pipe diameters, upstream and
downstream, from other line components. This is not always practical but it is important to design
in as much distance as possible. Interference may occur when valves are installed directly to
the outlet flange of a swing check, silent check, or reducing flange. Check valve and butterfly
valve combinations are very popular; normally a short spool piece is required between the
valves.
When using a valve with gear operator attached, it may be desirable to have the hand wheel
positioned to allow easy access, or for use of an optional adjustable sprocket rim (chain wheel)
for remote operation. Before valve installation, please review Gear Operator Installation and
Hand Wheel Positioning section of this booklet. These instructions illustrate how to orient the
