Drop tube assembly
View Patent ↗This drop tube loading arm assembly is adaptable for loading asphalt into tank trailers at marketing terminals. The telescoping drop tube employs guides made of polymers such as fluorocarbon polymers and aluminum. The guides are located in the annular space between the tubes in combination with increased radial clearance between the tubes or sleeves and in combination with protection for the overfill probe. With the addition of vapor control systems and overfill protection probes, the telescoping drop loading spouts are less susceptible to cold weather sticking problems.
1. A telescopic drop tube assembly for use with a tank while filling the tank from a liquid source, the assembly comprising:
a first hollow drop tube having a length, a hollow interior, an exterior, an upper end adaptable for coupling to the liquid source and a lower end;
a second hollow drop tube having a length, a hollow interior, an exterior, an upper end, a lower end;
a spout connected to the lower end of the second hollow drop tube adaptable for coupling to a tank,
wherein a portion of the upper end of the second drop tube circumscribes and forms a sleeve around an exterior portion of the lower end of the first drop tube;
wherein the second drop tube is slidably mounted around the exterior of the first drop tube;
a fluid overfill detector probe connected to the spout;
a vapor recovery nozzle connected to the spout; and
a guide connected to the interior second drop tube and slidably mounted against the exterior of the first drop tube.
2. A drop tube assembly according to claim 1 wherein a glide rail is connected to the exterior of the first drop tube, wherein the second drop includes an annular slot, wherein the annular slot is slidably mounted against the glide rail.
3. A drop tube assembly according to claim 1 including circuitry and a monitor wherein the circuitry connects the fluid overfill detection probe to the monitor.
4. A drop tube assembly according to claim 3 including a controller and circuitry wherein the circuitry connects the controller between the monitor and the liquid source.
5. A drop tube assembly according to claim 1 including a vapor recovery hose and a vapor recovery manifold wherein the vapor recovery hose connects the vapor recovery nozzle to the vapor recovery manifold.
6. A drop tube assembly according to claim 1 wherein the liquid source is an asphalt marketing terminal.
7. A drop tube assembly according to claim 1 wherein the tank is a mobile tank trailer.
8. A drop tube assembly according to claim 1 wherein the polymer guide is a fluorocarbon polymer guide.
9. A drop tube assembly according to claim 1 wherein the polymer guide is a tetrafluoroethylene (TFE) fluorocarbon polymer guide.
10. A drop tube assembly according to claim 1 wherein the guide is an aluminum guide.
11. A drop tube assembly according to claim 1 including a protective plate connected to the spout to protect the fluid overfill detector probe.
12. A drop tube assembly according to claim 1 wherein the spout comprises a pair of hollow, concentric tubes with a void therebetween.
13. A drop tube assembly according to claim 12 wherein the concentric tubes of the spout comprise an interior tube and an exterior tube wherein the interior tube circumscribes the lower end of the second hollow tube of the drop tube assembly.
14. A drop tube assembly according to claim 13 wherein the vapor recovery nozzle extends through the exterior tube of the spout and communicates with the void between the concentric tubes.