Flygt Ball Check Valves

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1 4/13 Supersedes: 6/96 The basic purpose of a check valve is to permit flow in one direction, prevent flow in the opposite direction and perform this function automatically and with minimum maintenance. In pumping applications, the head loss (pressure drop) across valves is also an important factor to be considered. The Flygt ball check valve meets all these requirements by providing a positive back flow prevention, minimum maintenance and low friction losses. Flygt ball check valves offer great operational reliability because of their construction and working principle. Its construction consists of just three components: body, cover and ball, the check ball is the only moving part. The underlying principle of the ball check valve is just as simple as it is effective. The valve housing has three openings: one for the inflow of fluids, one for the outflow of fluid and another for positioning the ball inside the valve housing which is closed off by a bolted cover. Normally, the rubber-coated ball closes off the inflow opening. The ball is released from its seating when the slightest difference in pressure occurs. As soon as the fluid flows through the valve, the ball slides away from the flow of fluid along both guide rails. The inlet is then completely free. If the fluid pressure drops, the ball then slides back into the valve seating again and closes off the opening completely. This stops the backflow of fluid and prevents any unnecessary damage to pumps. The Flygt check valve keeps solids, stringy material, grit, rags, etc. moving without the need for back flushing. The ball rolls clear of the water way providing full flow equal to the nominal size. There is no place for stringy material to wrap around; no pockets for sediment to collect; it is basically a non-clog check valve. There are no outside levers, weights, springs, dash pots or other accessories needed to correct the deficiencies of the swing (clapper) check valve. The ball is hollow metal with an exterior coating of nitrile rubber, which is resistant to grease, petroleum products, animal and vegetable fats, dilute concentrations of acids and alkalies (P 4-1), tearing and abrasion; has a high load bearing capability and low compression set. The ball rotates and thus seats on a different portion of its surface each time. These features prevent excessive wear and deterioration, therefore, assures a long useful life without costly maintenance and down time. Since the ball is only slightly heavier than water, the energy needed to move the ball to full open position is small compared to that necessary to lift a clapper, lever, weight (or spring) plus bearing and packing friction of a swing check valve. Net result is less head loss (pressure drop) through a Flygt check valve. The following advantages make Flygt ball check valves extremely suitable for use in sewage and storm water systems: Reliable operation without the danger of clogging. Efficient operation even with small pressure differences. No wear under normal conditions. Maintenance-free and long life. Standard sizes are rated for: Working pressures of up to 145 psi (1 bar). Working temperatures of up to 176 F (8 ). Special version for higher pressures and temperatures available on request. When necessary, valves can be supplied to meet special requirements such as materials, coatings, special balls, etc. If valve installation in the collection basin (wet well) is not permissible, it can be directly buried in the ground - no vault necessary. Normal Flow Back Flow Prevention

2 4/13 Supersedes: 1/6 Typical installations with an Flygt submersible pump. When the Flygt non-return valve is used in conjunction with a Flygt submersible pump, the resulting pump/valve system provides a degree of dependability that is second to none. Illustrated here are only some of the possible installation combinations. It is very important to install a ball check valve properly and following these few minor checks will insure a trouble free system operation: 1. Make sure that the valve is sized in the correct way. Rule of thumb: Valve size should be the same as the pipeline size. If size of the valve is bigger or smaller there must be a specific reason, check with the design engineers. PUMP ON Floating Ball Sinking Ball PUMP OFF - no backflow Operates in any position. The Flygt check valve comes equipped with either a sinking or floating ball. The unit can operate clog-free in any of the positions shown by using the appropriate ball. Up to 3 o angularity from these positions is permissible.. Pressure rating of the valve should be the same as that of the system. 3. Before installing the valve, perform a visual inspection for defects of body, cover or ball. 4. heck the movement of the ball. The ball should move freely through the valve housing. 5. Install the check valve with the arrow pointing in the flow direction. (away from the discharge side of the pump). 6. In cases of horizontal application minimum required head behind the valve is 1 ft. If 1 ft. is not available, please contact Flygt. 7. In cases of vertical application there are no head requirements. Note: To meet conditions of low static head, balls of various specific gravity can be obtained. onsult nearest Flygt products applications engineer when static head on valve is less than 1 feet.

3 Specifications 4/13 Supersedes: 1/13 Ball check valves shall be designed to be non-clog, fully automatic, maintenance free and specifically suited for operation in sewage and storm water where solids, fibers, grit or highly viscous materials are encountered. Ball check valves will have one moving part, the ball, which automatically rolls out of the path of flow, thus providing an unobstructed and "full flow" equal to nominal size. Upon discontinuation of flow the ball automatically rolls back to the closed position, thus providing a positive seal against back pressure or backflow. and cover shall be nodular cast iron type GGG 4/ASTM /SAE 451.Ball check valves are designed to be maintenance-free and suited for installation in the horizontal or vertical position. The valve shall be so constructed that by unbolting and lifting off the cover, the ball may be removed and replaced without removing the valve from the line. Ball check valves will be available with either a floating or sinking ball. The valve shall be equal in all respects to model 587 as supplied by Flygt. The ball shall have an exterior coating of vulcanized nitrile rubber resistant to grease, petroleum products, animal and vegetable fats, dilute concentrations of acids and alkalies, tearing and abrasion. The body

4 Type 587 4/13 Supersedes: 8/3 All dimensions (inches) Nominal Size Part Number A D Weight lbs. D A *" *-1/" 3" 4" 6" 8" 1" 1" 14" 16" " 4" Notes: Flanges drilled to lass 15 ast Iron Standard. Dimensions for stainless steel valves may vary, consult Factory. *ontact Flygt for " & -1/" valve performance information. Design Features: Body: Nodular ast Iron -- Type GGG4/ASTM /SAE D451 Flange Drilling: ANSI B16.1 lass 15 Flat Faced Bolt holes straddle centerline. Ball: Metal core with vulcanized Nitrile rubber covering. Sinking Type: Floating Type: Working Pressure: greater than 1. less than psi max. Working Temperature: 176 F max. (1 F max. with optional EPDM-coated ball). Application: Generally used for sewage and storm water. For other flowing media, various types of coatings and ball elastomers are available. Details are required for proper evaluation. Friction oss (ft) " Friction oss (ft) " 6" Valve performance (with sinking ball) 8" 1" 1" 14" x 1 (GPM) 16" " 4" x 1 (GPM)

5 Type 4/13 Supersedes: 7/3 AP BA SEAANT BODY Nominal Size Part Number All dimensions (inches) Weight lbs. 3/4" 1" 1-1/4" *1-1/" /4 1-5/8-5/ /8 4-3/8 5-3/8 6-1/4 7-5/ * Also available in Stainless Steel - consult Factory - Design Features: Application: Body: ap: Ball: Bronze -- Female Thread Bronze, Threaded Sealant: octite pipe sealant #57 Metal core with vulcanized Nitrile rubber covering. Sinking Type: greater than 1. ompressed air and water systems, including potable water. Any liquid or gas compatible with bronze, nitrile rubber or stainless steel. Note: When the static head on the outlet side of the check valve is less than 1' of water or 4 psi, valve should be installed in the vertical position only. Floating Type: Working Pressure: Working Temperature: less than psi max. 176 F max.