一般的安装知识
General Installation Information

　　如果采用法兰结构形式，则美国斯毕尔公司蝶阀既可用于连接在两个法兰之间，也可用于终端或末端的单侧（只有一侧法兰）连接。法兰内嵌阀门要求注意流向，真法兰阀门能够双向安装。阀门手柄（或齿轮操作机构）可反转180^o，既可左侧操作，也可右侧操作。美国斯毕尔公司蝶阀安装要求用户自备3.2毫米厚全面垫圈，六角螺栓，螺母和平垫圈。
　　Spears® Butterfly Valves are designed for system connections either between two flanges, or with single-side (flange one-side only) connection for dead-end service using lug style valves. Lug Insert Valves require attention to flow direction, True Lug valves may be installed either direction. The valve handle (or gear operator) is reversible 180^o for either left or right side operation. Spears® Butterfly Valves are designed for installation with user supplied ¹/₈" full-faced gaskets, hex bolts, nuts and flat washers.
　　注意：美国斯毕尔公司蝶阀适用于安装在法兰或带有法兰的设备之间，其内部最小流道面积不能小于管道壁厚Schedule 80的PVC材质管道（ASTM D 1785）的流道面积。如果采用的法兰连接装置的内部直径较小，则可能导致阀门阀瓣的阻塞和损坏。
　　Caution: Spears® Butterfly Valves are designed for use with flanges or flanged equipment having minimum waterway inside diameter no less than that of Schedule 80 PVC pipe (ASTM D 1785). Use of smaller inside diameter flange connections may result in obstruction and damage to the valve disc.

1. 最小螺栓长度以采用美国斯毕尔公司法兰，3.2毫米厚度全面垫圈，标准S.A.E.六角螺栓和标准盘“W”系列平垫圈等因素为基础进行计算。
   Minimum bolt lengths based on use of Spears® flanges, ¹/₈" full faced gaskets, standard S.A.E. hex bolts and Standard Plate "W" Series flat washers.
2. 所指定的螺栓长度是指在不移动阀门前提下，预计需要安装第2个法兰的地方进行初始单侧法兰安装时保持正确间隔所要求的最大容忍值。
   Specified bolt lengths are maximum allowable for maintaining proper clearance in initial Single-Side installation with Lugs where anticipated 2nd Flange installation option is to be retained without removal of valve.
3. 穿过两个法兰、两个垫圈、两个平垫圈和一个阀体所需的最短螺栓长度。
   Minimum bolt length through 2-flanges, 2-gaskets, 2-flat washers and 1-valve body.

单侧（一侧法兰）安装采用带法兰内嵌件的标准阀门
（用于现场安装内嵌套件或工厂已安装法兰内嵌件的阀门）
Single-Side (flange one side) Installation Using Standard Valve with Lug Inserts (for
field installable Insert Sets or valves with factory installed Lug Inserts)

警告：法兰必需安装在阀门的一侧，另一侧
用于单侧安装的六角螺母凹进处如图所示。
CAUTION: Flange must be installed on side of valve opposite
the hex nut recesses for Single-Side Installation as illustrated.

（不包括法兰，螺栓，螺母，垫圈和衬垫。
法兰内嵌件可以另行订购。）
(Flange, bolts, nuts, washers and gaskets not included.
Lug inserts may be ordered separately.)

聚丙烯蝶阀力矩和五金件的必要条件
Polypropylene Butterfly Valve Torque and Hardware Requirements

螺栓长度将随着阀门厚度，匹配的法兰，
螺母和所采用得着衬垫等因素而变化。
Bolt lengths will vary according to thickness of valve,
mating flanges, nuts and gaskets used.

下列公式可用于计算安装每一侧匹配法兰的螺栓长度。
The following formula may be use to calculate bolt length
for installation with mating flange each side.

L = V + 2 (F + G + W) + N