Flow control valve and method for rebuilding a flow control valve
View Patent ↗A method for rebuilding a flow control valve, may be performed by first providing a flow control valve having a rotor positioned in a chamber of a valve body. The rotor has a valve stem. A top cover plate is mounted to the valve body above the rotor and has a first bore through which the valve stem protrudes. The top cover plate is removed so the rotor can be removed from the valve body. A seal is positioned on the top cover plate along the first bore so that when the rotor and top cover plate are placed in or on the valve body, the flow control valve is sealed at the interface between the top cover plate and the valve stem.
1. A method for rebuilding a flow control valve, comprising the steps of:
providing a flow control valve having a rotor positioned in a chamber of a valve body, and the rotor having a valve stem, which has an outside diameter, and a top cover plate mounted to the valve body having a first bore through which the valve stem protrudes, and the first bore having a diameter;
removing the top cover plate and rotor from the valve body;
reducing the outside diameter of at least a portion of the valve stem to a predetermined outside diameter;
positioning a bushing on the valve stem over the portion of the valve stem of which the diameter has been reduced;
forming a second bore in the top cover plate that is coaxially aligned with respect to the first bore and the second bore having a diameter that is larger than the diameter of the first bore thereby forming a lip between the first bore and second bore;
positioning a seal on the lip in the top cover plate;
inserting the rotor into the valve chamber of the valve body; and
positioning the top cover plate over the rotor so the valve stem protrudes through the first bore and second bore in the top cover plate, and the seal is disposed between the top cover plate and the bushing on the valve stem.
2. The method of claim 1 further including the step of cleaning any surfaces of the rotor and the valve body.
3. The method of claim 1 wherein an o-ring is positioned on the valve stem and the method further comprises the step of removing the o-ring.
4. The method of claim I wherein the flow control valve has a plurality of seal pads disposed between the rotor and the valve body, and the method comprises the steps of removing the seal pads, cleaning the seal pads and inserting the seal pads in the valve body between the rotor and valve body.
5. The method of claim 1 wherein the flow control valve includes a bottom cover plate mounted to the valve body and the method further comprises the steps of removing the bottom cover plate and mounting the bottom cover plate to the valve body before inserting the rotor into the valve body.
6. The method of claim 5 wherein the flow control valve includes a first washer disposed between the top cover plate and the rotor and a second washer disposed between the bottom cover plate and the rotor, and the method further comprises the steps of removing the first washer and second washer after the top cover plate and bottom cover plate have been removed and positioned the second washer in the valve body after attaching the bottom cover plate to the valve body and before the rotor is inserted into the valve body, then positioning the first washer over the rotor after inserting the rotor in the valve body and before attaching the top cover plate to the valve body.
7. A method for rebuilding a flow control valve, comprising the steps of:
providing a flow control valve having a rotor positioned in a chamber of a valve body, and the rotor having a valve stem having an outside diameter, and the flow control valve having a top cover plate mounted thereon wherein the top cover plate has a first bore through which the valve stem protrudes;
removing the top cover plate from the flow control valve;
removing the rotor from the valve body;
reducing an outside diameter of at least a portion of the rotor valve stem;
adapting the valve stem to account for the reduced diameter;
positioning a seal on the top cover plate along the first bore by forming a second bore in the top cover plate that is coaxially aligned with respect to the first bore and the second bore having a diameter that is larger than the diameter of the first bore thereby forming a lip between the first bore and second bore, and positioning the seal on the lip in the top cover plate;
inserting the rotor into the valve chamber of the valve body; and
positioning the top cover plate over the rotor so the valve stem protrudes through the first bore in the top cover plate, and the seal is disposed between the top cover plate and the valve stem.
8. A method for rebuilding a flow control valve, comprising the steps of:
providing a flow control valve having a rotor positioned in a chamber of a valve body, and the rotor having a valve stem having an outside diameter, and the flow control valve having a top cover plate mounted thereon wherein the top cover plate has a first bore through which the valve stem protrudes;
removing the top cover plate from the flow control valve;
removing the rotor from the valve body;
reducing an outside diameter of at least a portion of the rotor valve stem to a predetermined outside diameter;
adapting the valve stem to account for the reduced diameter;
positioning a bushing on the valve stem over the portion of the valve stem of which the diameter has been reduced;
positioning a seal on the top cover plate along the first bore;
inserting the rotor into the valve chamber of the valve body; and
positioning the top cover plate over the rotor so the valve stem protrudes through the first bore in the top cover plate, and the seal is disposed between the top cover plate and the valve stem.