The risk is highest with automated valves. The instructions and list of spare parts in this document are applicable Take necessary safety precautions to avoid unintentional to the NAF Duball DL Pocket Valve in accordance with our Technical stroking of the actuator / valve. Bulletin NFENTB4163.
Figure 1: Schematic lifting of a valve with mounted actuator. Note that the final lifting of the valve into a vertical pipe requires different lifting A typical application for the NAF Duball DL Pocket Valve is when it’s installed points.
5 Operating sequence recommended that the Pocket ball remains in this position for at least The NAF Duball DL Pocket Valve is operated by the following sequence: 10 seconds. However, due to the nature of the debris in the Pocket ball, 1.
7 Operation Table 1: The total volume of the Pocket ball cavity The NAF Duball DL Pocket Valve is installed to safely remove sand/ debris out of the process as effectively as possible while maintaining When the Pocket Valve is taken into operation, it is recommended that process pressure.
NAF Duball DL Ball Valves NFENIM4163-00-A4 05/17 8 Bill of Materials and recommended spare part kits 11 12 16 6 Figure 5: Exploded view with item/part numbering Item Part Item Part Body, main Anti-friction Washer Body, cover Body seal Pocket Ball...
Remove the body cover (2). inspected regularly and any issues should immediately be corrected. As the NAF Duball DL Pocket Valve is used in high wear and high cycle Remove the ball (3), which is done when the ball is in the applications, we highly recommend that an inspection is performed position shown in Figure 6.
NAF Duball DL Ball Valves NFENIM4163-00-A4 05/17 10.3 Reassembly of the valve There should be a small gap between the Pocket ball and the To replace parts, see sections 10.4-10.6 below. After the inspection seat ring to get the correct torque while restricting big particles and/or part replacements have been made, reassemble the valve as from entering the body.
If the sealing areas on the Pocket ball are damaged, we recommend that the valve is returned to Flowserve for overhaul. This applies in particular if the ball must be reground before lapping. Assemble the valve before dispatching it to Flowserve NAF.
NAF Duball DL Ball Valves NFENIM4163-00-A4 05/17 Figure 9.Stem packing Assemble and, if possible, pressure test, the valve as described in Section 10.3. However, first assess whether the seat rings (4) and pocket ball (3) should be replaced. 11 Fitting an actuator to the Pocket Valve Fit the actuator to the valve.
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Flowserve product is designed to perform its intended function safely during its useful life. However, the purchaser or user of Flowserve products should be aware that Flowserve products might be used in numerous applications under a wide variety of industrial service conditions. Although Flowserve can (and often does) provide general guidelines, it cannot provide specific data and warnings for all possible applications.
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