What Are The Best Delayed Coker Maze Pit / Clearwater Pumps?
The pumping of water packed with coke fines produced by the jet cutting process in a Delayed Coker Unit (DCU) is an aggressive application. Pumps commonly fail or have reduced operating lives for a variety of reasons including: heavy fines loading, challenging suction conditions, high temperatures, and deep set sumps all combine to create a harsh environment that constantly takes pumps out of operation and puts them into the repair shop.
What the application requires is a pump that can withstand all of the following challenges
- Inadequate lineshaft bearing lubrication due to high temperatures and solids ingress.
- The collapse of accumulated solids which can bury the pump’s wet end and choke the suction with solids.
- Seal and lower bearing failures resulting from the cavitation that is created by the higher temperatures and ensuing low NPSHa, as well as from the restricted sunction that results from solids accumulation.
- Seal and lower bearing failures resulting from clogging with fines, as well as the reverse flow and potential reverse rotation that can occur upon shutdown due to faulty check valves.
- Overheating of submersible motors.
Inherently, our HNS submersible eliminates the Lineshaft bearings which are a prime source of failure in vertical pumps. The removal of these bearings means that there is no need to worry about improper lubrication, solids ingress on the lower bearing, or shaft binding caused by the temperature differences between the bearing column and discharge pipe. Lineshaft bearings are negated altogether!
Our patented Plenum 54™ system combined with our proprietary XD seal are designed specifically to function in environments with high solids and fines concentrations, abusive suction conditions where cavitation is common, and where the pump and rotating assembly can see heavy loading due to high solids and/or extreme operating fluctuations.
To further provide solutions to these application issues, the Hevvy HNS is supplied with our patented agitator and jet ring. These key items work to keep the zone underneath and around the pump’s suction clear of solids, while also fluidizing the solids in the event that a submerged “wall” of solids collapses onto the pump. During the reinstallation of the pump, the powerful jet ring can also clear a path to the sump floor through the solids accumulated in its absence. The jet ring combined with the submersible configuration provides a powerful alternative to this challenge faced by vertical pumps.
So how do you install a vertical pump into a sump that is effectively shallower than when the pump was removed? With the HNS submersible and jet-ring, this challenge is eliminated.
At the heart of this system is the HNS motor and rotating assembly. Designed with a robust L/D ratio < 1 (our patented “run-dry” technology) and built on a modular format, the HNS provides security in the toughest applications as well as flexibility for the future. The modular concept allows for multiple benefits:
- Spec your own service factor; 1.35, 1.5, 2.0, 3.0….? Our wet-ends are interchangeable across a broad range of motor sizes, thus allowing you to customize the service factor. Whether you want to “supercharge” your rotating assembly, or drive down internal loads and operating temps, the HNS’ modular design allows you to do so.
- The HNS is interchangeable across all our wet end designs. If operating conditions change, or you want to repurpose the pump into another application, the HNS design allows you to swap out the wet-end, or the motor to meet your new requirements.
The HNS can even be attached to a column and mounting plate in a pseudo VS4 configuration to retrofit existing problem pumps, while maintaining the current piping configuration.
Speak with one of our Coking experts to find out how we can help improve the reliability of your decoking sump pumps.