API 7-1 Oil Well Downhole Tool / Fishing Tool Junk Bit Sub / Fishing Cup

Descriptions of Junk Sub:

Junk Sub (Fishing Cup) is normally used to catch and remove junks that are too heavy to be circulated preventing them from settling at the bottom of the well-bore. Typical junks are shivers and fallen objects such as carbide tooth, drill bit and bearings which are too heavy to be removed from the well-hole through conventional fluid circulation. Junk Sub’s main function is to keep well bottom clean to increase bit service life, reduce and prevent drill bit from unexpected damage.

Structure

As the outer diameter of the external bowl is bigger, the space between the external bowl and the well hole is reduced guiding most of the fluid through the cup. The mandrel diameter at the cup mouth is bigger with larger annular space. Thus, the fluid forms a swirl at the cup mouth as the fluid flows down through the cup with a sudden reduction in capacity at the bottom. Through this working principle, some heavy objects will drop in the cup and be fished out, ensuring that the well-bore bottom is cleaned.

The Junk Sub an accessory tool used in milling or drilling operations. It is designed to prevent cuttings that are too heavy to be circulated from settling to the bottom of the hole.

The standard junk sub is a welded assembly with a 10 inch deep cup. Long and extra long baskets are available; these provide a 20 or 30 inch deep cup.

Junk Subs are manufactured from 4140HT or 4145M alloy steel.

When ordering, please specify:

• Hole Size or Desired Cup OD
• API connection size (ex. 4-1/2” API REG pin up x 4-1/2” API REG box down)
• Length of cup: 10”, 20” or 30”

Specification of Drilling Junk Sub

Complete fishing tools we supply:

We provide all kinds of fishing tools at various sizes. The fishing tools are produced and inspected strictly under API Spec 7, including Safety Joint, Fishing Magnet, Overshots, Releasing Spear, Fishing Jar (3 1/2" to 9 1/2" OD), Fishing Multifunction, Casing Spear, Taper Taps, Die Collars, Jar Intensifier (3 1/2" to 9 1/2" OD), Junk Sub, Hydraulic Junk Retriever, Mill Shoes, Reverse Circulating Junk Basket etc.