DeZURIK
Willamette AWWA Metal Seated Ball Valve
January 2022
Page 4
D12001
Description
General
DeZURIK’s Willamette AWWA Metal Seated Ball Valve (VBL) is a ball type, quarter-turn valve with a full-ported
circular waterway through the body and ball in the open position. Each ball valve typically consists of four (4)
main elements: a pressure vessel (body), a rotatable closing element (ball), a torque unit, and an operator. The
"standard" material of construction for the body is ductile iron; standard ball materials are ductile iron, carbon
steel or 316 stainless steel. Ball valve construction is in complete accordance with
AWWA Standard C507 for
Ball Valves 6 In Through 60 In
.
Body
The standard body has ASME B16.42 Class125/150 or Class 250/300 flanges and houses the ball. The body
has integrally cast trunnions and provides rigid means for supporting the torque unit (without the necessity of
additional supports). There are two (2) pipe connections, one for an air vent and the other for drain. The body
has rigidly attached corrosion resistant metal seat(s).
Ball
The ball has bronze-bushed trunnions. An extension of one trunnion, called the operating shaft, passes
through a sealing device (o-ring retainer) and connects to the torque unit. The operating shaft is stainless steel
or chrome plated carbon steel. The sealing device is capable of being removed and having its seals replaced
without removing the valve from the line.
The ball has corrosion resistant metal seat(s) rigidly attached and fully adjustable to provide tight sealing in
accordance with AWWA standard C507 in one direction or both directions, as an option. The ball shaft is
designed for a factor of safety for all combined stresses of at least five to one.
Torque Unit (Valve Operating Mechanism)
The torque unit employs a traveling crosshead to impart positive rotary movement to the ball by means of a link
and lever connected to the ball shaft. A ball shaft support bearing is supplied on the cover. The torque unit is
designed such that during the first 50 percent of stroke in closing, the flow area is reduced by approximately 81
percent. The remaining flow area is gradually reduced to a complete shutoff throughout the last 50 percent of
closing stroke. Likewise, when opening, the first 50 percent of the stroke gradually opens the first 19 percent.
The last half of the stroke opens the valve completely. All materials of the torque unit subject to rubbing are of
different hardness. The torque unit is capable of being inspected, lubricated, removed and repaired without
removing the valve from the pipeline.
Handling and Storage
Lifting the valve improperly may damage it. Do not fasten lifting devices to the
actuator, ball or through the seat
opening in the body. Lift the valve with
slings, chains or cables fastened around the valve body, or fastened to
bolts or
rods through bolt holes in the flanges.
If installation will be delayed, place valve indoors in secure, weather tight storage. If temporary outside storage
is unavoidable, make sure a vermin proof rain cover (water shedding tarp, etc.) is secured around/over the
equipment to keep off rain and mud. Skid and set the assembly on a flat, solid, and well drained surface for
protection from ground moisture, runoff and pooled rain water.