NIBCO Wafer Style Flanged Flangeless 910-960-Series Silent Check Valves - Manual

INSTALLATION, OPERATION & MAINTENANCE INSTRUCTIONS
CAUTION: Only qualified personnel should undertake the procedures outlined in this document.
NIBCO INC., its agents, representatives and employees assumes no liability for the use of these
procedures. These procedures are offered as suggestions only.
NIBCO Technical Services • Phone: 1.888.446.4224 • Fax: 1.888.336.4224
1
N I B C O I N C .
W O R L D H E A D Q U A R T E R S
1 5 1 6 M I D D L E B U R Y S T.
E L K H A R T, I N 4 6 5 1 6 - 4 7 4 0
U S A
P H O N E : 5 7 4 . 2 9 5 . 3 0 0 0
F A X : 5 7 4 . 2 9 5 . 3 3 0 7
W E B : w w w . n i b c o . c o m
Review Date: 01/18/2012
Original Date: 04/07/1996
Operating, Maintenance and Installation Instructions for
NIBCO
®
Flanged End and Wafer Style Check Valves
(Series 910 & 960)
WARNING NOTICE:
1. Damage to the valve and/or internal leakage may result if pipe flanges other than
those with standard flat faces, conforming to ANSI B16.5 or AWWA C207-86, are
used. Flanges having an expanded inside diameter (often found on mortar lined
pipe) cannot be used on the inlet side of the valve. A ring flange having a maximum
inside diameter as shown in “A” dimension (see next page) must be inserted
between the valve and mortar lined pipe flange.
2. Proper centering of ring gasket is important to prevent internal valve leakage.
3. The valve and adjacent piping must be supported and aligned to prevent stress
from being transferred to the valve’s flanges. The torquing of the flange bolts
should then be done in several graduated steps, using the number sequence
shown below. This even loading of the flange bolts will eliminate concentrated
stresses which could fracture the valve’s flange.