Description
ELITE supplies reverse circulation junk baskets and junk subs for drilling, milling and fishing operations. The tools are manufacturing from heat-treated alloy steel and machined to the required dimensions and API connections.
Standard configurations are available for common hole sizes, while custom OD, bore, cup and connection dimensions can be producing for specific BHA designs.
The two tools serve different purposes in the BHA.
A Reverse Circulation Junk Basket (RCJB) is using when loose junk is already sitting at or near the bottom of the hole and needs to be recovering into the basket.
A Junk Sub is using during drilling or milling to provide a collection space for heavy debris and coarse cuttings that may otherwise settle back into the hole.
In simple terms, an RCJB is primarily a bottom-hole recovery tool, while a junk sub is primarily a debris-collection tool.
Which Fishing Tool Do You Need?
Junk Basket
Used to recover small, loose debris from the bottom of the hole—such as bit cones, hand tools, and slips—before drilling or fishing operations can safely continue.
Junk Sub
Used to collect larger cuttings and debris generating during milling or drilling operations that cannot be circulating out effectively.
Not sure which tool is right for your situation?
[Tell us what you are dealing with, and we’ll recommend the appropriate tool ]
Email: info@apidrillpipe.com
WhatsApp: +8618615995257
ELITE Junk Basket
| Model | O.D. of mill mm (in) | Max.O.D. of fish mm (in) | Steel ball mm (in) | Suitable well diameter mm (in) | Connection API |
| RS32 | 84(3 5/16) | 52(2 1/16) | 30(1 3/16) | 98~108(3.86~4.25) | NC26 |
| RS34 | 89(3 1/2) | 55(2 5/32) | 28(1 3/32) | 98~108(3.86~4.25) | NC26 |
| RS150Ⅱ | 386(15 3/16) | 318(12 1/2) | 45(1 25/32) | 406.4~444.5(16~17.5) | 7 5/8REG |
| RS200 | 513(20 3/16) | 406(16) | 45(1 25/32) | 530~660(20.86~26) | 7 5/8REG |
The Reverse Circulation Junk Basket is designing to recover small pieces of junk from the bottom of the well, including bit cones, hand tools, slips and other loose metal debris.
The tool uses reverse circulation to lift the debris into the internal catcher. Depending on the configuration, it can also be using for specializing coring applications.
ELITE Junk Sub
| Model | Hole size mm | Cup O.D. mm(in) | Diam. Of Bore mm (in) | Connection API | Cup I.D mm(in) | O.D of Top Connection mm (in) |
O.D of Under Cup mm (in) |
| RS102 | 117.5～ 127 | 102(4) | 31.8(1.25) | 2-7/8REG | 92(3.62) | 95(3.74) | 66.7(2.63) |
| RS114 | 130.2～149.2 | 114 (4-1/2) | 38.5(1.52) | 3-1/2REG | 106(4.17) | 108(4.25) | 79(3.07) |
| RS245 | 292.1～330.2 | 245 (9-5/8) | 70(2.76) | 6-5/8REG | 217(8.54) | 197(7.75) | 146(5.74) |
A junk sub is installing in the drill string or milling assembly to collect heavy cuttings and debris that cannot be transporting effectively to surface by normal fluid circulation.
As drilling fluid passes the tool, the larger external diameter of the junk cup creates a low-velocity collection area. Heavy debris can fall out of the returning fluid and accumulate inside the cup instead of returning to the bottom of the hole.
How Does a Reverse Circulation Junk Basket Work?
The tool is run close to the bottom of the hole and circulation is establishing. On designs using a circulating ball, the ball is droppin to activate the reverse-circulation path. Fluid is then redirected through the lower ports, creating the flow pattern needing to lift loose debris into the internal catcher.
Once the junk has been capturing, the tool is pulled to surface and the basket is opening for inspection and debris recovery.
How Does a Junk Sub Work?
A junk sub does not use the same reverse-circulation principle as an RCJB.
Instead, the junk cup creates a collection area around the tool. As drilling fluid and debris move upward through the annulus, fluid velocity changes around the enlarged cup area. Heavy particles and metal fragments that cannot remain suspended can settle into the junk cup.
The collected material is recovered when the string is pulled to surface.
This makes the junk sub especially useful for continuous debris collection during drilling or milling, rather than a dedicated fishing run for one loose object.
Reverse Circulation Junk Basket vs Junk Sub
| Feature | Reverse Circulation Junk Basket | Junk Sub |
|---|---|---|
| Main function | Recover loose junk from bottom | Collect heavy circulating debris |
| Typical operation | Dedicated fishing operation | Drilling, milling or cleanout |
| Working principle | Reverse circulation | Debris settling in junk cup |
| Typical debris | Bit cones, cutters, bearings, small tools | Milling debris, coarse cuttings, heavy fragments |
| Catching method | Internal catcher/basket | External junk cup |
| Steel ball activation | Used on applicable designs | Not normally required |
| Mill shoe | Available | Not primary feature |
| Best suited for | Loose identifiable junk on bottom | Continuous debris collection |
| Tool retrieval | Pull after fishing cycle | Inspect after drilling/milling run |
If the downhole condition is uncertain, send us the hole size, type and approximate size of the junk, planned drilling or fishing operation, BHA connection and available circulation parameters.
ELITE can review the application and recommend whether an RCJB, junk sub, fishing magnet or overshot is more appropriate.
ELITE can help determine whether an RCJB, junk sub, fishing magnet or overshot is more appropriate.
