If the document is revised or amended, you will be notified by email. You may delete a document from your Alert Profile at any time. This standard is also available to be included in Standards Subscriptions.
Standards Subscriptions from ANSI provides a money-saving, multi-user solution for accessing standards. Subscription pricing is determined by: the specific standard s or collections of standards, the number of locations accessing the standards, and the number of employees that need access. As the voice of the U. Available for Subscriptions. Please first log in with a verified email before subscribing to alerts.
Please first verify your email before subscribing to alerts. Already Subscribed to this document. Unless otherwise specifically requested by the purchaser, bodies of valves shall be of gray iron, ductile iron, or alloy-gray iron. To learn more about pricing, product customizations, delivery times and more, please call United Water Products directly at or send us an email through our Contact form.
Hydraulic testing, flow capacities, and valve torques are based on the flow, upstream of a valve, being uniform and undisturbed, like the flow produced by a long length of constant-diameter, straight pipe. Rubber seats shall be recessed in the valve body.
A smaller handwheel may require a more expensive actuator requiring more turns. A of this Foreword. Whenever valve components are to be made in conformance with ASTM or other standards that include test requirements or testing procedures, the valve manufacturer shall meet these requirements or procedures. For any overlay, the following performance items are required: No part of the valve internals shall extend beyond the body ends when the disc is in the closed position.
Laying lengths for class 25, 75, and flanged-end and wafer valves shall be as specified in Aww 1. Protective coatings, if other than specified in Sec. Full-face flange protectors of waterproof plywood or weather-resistant pressboard, of at least the outside diameter of the flange, x be fastened to each flange to protect both the flange and the valve interior. Direction to turn the handwheel, chainwheel, or wrench nut to open valves.
Laying lengths do not apply to class B flanged-end or mechanical-joint end valves. The adequacy is to be demonstrated by testing valves selected to represent each basic type of seat design in each applicable size group in Table 6 and in a pressure class or classes equal to or greater than the valves being purchased.
The valve is bubble tight at full rated pressure allowing for dead end service. Minimum body shell thicknesses shall conform to the requirements listed in Table 1. Bearings awwq be zwwa for a pressure not to exceed the published design load for the bearing material or one-fifth the compressive strength of the bearing or shaft material. All actuator components aww be capable of withstanding an input torque of ft-lbs. The cylindrical journal xwwa in the body hubs that is used to support the valve shaft s and transmit disc forces to the valve body while minimizing friction and wear.
All valve shafts shall be one piece of two piece stub-shaft type or ground and polished stainless steel. The valve shall have a clear inside diameter equal to the stated nominal diameter. Determine additives requirements, including applicable standards. It is the responsibility of the user of an AWWA standard to determine that the products described in that standard are suitable for use in the particular application being considered.
A device attached to the valve for the purpose of rotating the valve disc to an open, closed, or intermediate position; preventing disc overtravel; and maintaining the disc in any position. If awsa oversize actuator with no means of limiting torque is used, stop the actuator before the valve is fully opened or closed against stops and complete awwwa operation manually.
Actuators used for modulating service shall be rated to produce not less than twice the required valve aawa torque. Producers of goods made in conformity with an American National Standard are encouraged to state on their own responsibility in advertising and promotional materials or on tags or labels that the goods are produced in conformity with particular American National Standards. Leak tightness shall be demonstrated by mating-seat performance during a min, psig 1,kPa proof-of-design gas leakage test.
If this is a concern, requirements on actuator mounting should be included in the purchase documents. This may not be a standard practice for some manufacturers and, therefore, may result in increased cost and delivery time. Model Data Sheet. Refer to item 28 of Sec.
0コメント