Deaerator spray nozzle and related methods
A spray nozzle assembly and hub combination for operation in a boiler feedwater deaerator is disclosed, the combination including a tubular hub capable of being affixed to a wall of a deaerator tank and a spray nozzle assembly that is removably engageable with the hub, the nozzle assembly including a nozzle body, a twist lock for retaining the nozzle body relative to the hub when the nozzle body is in a fully engaged position, and a spreader moveably coupled to the nozzle body and biased by a spreader spring against opening, the spreader is capable of moving to an open position against the spreader spring bias in response to boiler feedwater pressure to form an annular opening about the spreader, thereby enabling feedwater flow.
1. A spray nozzle apparatus for operation in a boiler feedwater deaerator, the apparatus comprising:
a spray nozzle assembly
including:
a nozzle body;
a twist lock adapted for retaining the nozzle body relative to a hub that is affixed to a wall of the deaerator when the nozzle body is in a fully engaged position; and
a spreader moveably coupled to the nozzle body and biased by a spreader spring against opening, the spreader is capable of moving to an open position against the spreader spring bias in response to boiler feedwater pressure to form an annular opening about the spreader, thereby enabling feedwater flow;
whereby the spray nozzle assembly adapted to be removably engageable with the hub.
2. The apparatus of claim 1 further comprising a longitudinal shaft that is coupled to the nozzle body and a retainer that is coupled to the shaft, wherein the spreader spring is in tension between the retainer and the spreader to provide the spreader spring bias.
3. The apparatus of claim 2 wherein the spreader contacts a rim of the nozzle body when the spreader is in a closed position.
4. The apparatus of claim 1 wherein the assembly further comprises the hub, and wherein the twist lock is actuateable at least in part by twisting of the nozzle body relative to the hub.
5. The apparatus of claim 4 wherein the twist lock includes a lock spring that biases against insertion of the nozzle body into the hub.
6. The apparatus of claim 5 further comprising a handle that extends past an outlet end of the nozzle assembly such that the nozzle assembly is configured to be insertable into the hub by actuation of the handle.
7. The apparatus of claim 6 wherein the twist lock includes pins extending from the nozzle body and corresponding J-shaped slots in the hub such that the nozzle assembly is engageable with the hub upon (i) insertion of the pins into open ends of the J-shaped slots against a lock spring bias and (ii) twisting of the nozzle assembly by means of the handle to move the pins to short legs of the J-shaped slots.
8. The apparatus of claim 7 wherein a lock spring is in compression between the nozzle body and a retaining surface on the hub while the nozzle assembly is in a fully engaged, operational position in which the pins are biased against the ends of the short legs of the J-shaped slots.
9. The apparatus of claim 1 wherein the nozzle assembly is configured to be engageable with the hub without tools.
10. The apparatus of claim 4 further comprising an O-ring between the body and the hub.
11. The apparatus of claim 10 wherein the body has a circumferential groove in which at least a part of the O-ring is retained.