Sub Assemblies

Drilling Tools offers a variety of subs in both AISI 4145 heat-treated steel and non-magnetic metal. Virtually any type of sub can be manufactured in-house to customer specifications. Listed below are a few examples:

Float Subs

Float subs are used to house the float valve within the BHA providing fluid flow control through the ID of the drill string. They prevent back flow of cuttings from plugging the drill bit jets when making connections. Float subs are available in a variety of sizes to accommodate the full spectrum of downhole drill stem sizes.

Lift Subs

Lift subs are offered with a flow through or as a conventional design in a variety of sizes to provide ease of handling long products or heavy downhole BHA components. Lift subs are specifically utilized during make-up or break-out operations. The sub's elevator recess and connections are machined to fit the elevator and drill collar connections, as per API specifications.

UBHO and Muleshoe Subs

UBHO and muleshoe subs are used in directional drilling BHA's and are typically run directly below a non-mag drill collar. This sub contains a landing sleeve that can be oriented to the directional survey equipment or mud motor scribe line. They are available in steel or non-magnetic material.

NOTE: UBHO subs are designed to allow mud flow while directional equipment is seated within the sleeve. Muleshoe subs are designed to be used when pumps are turned off while directional equipment is seated within the sleeve.

Filter Subs

Available in a variety of sizes, Drilling Tools' filter subs range from the retrievable and non-retrievable mud screens to the Diffuser™ blade technology sub assembly. See detailed information on Drilling Tools' Diffuser™ downhole filtering technology.

Pup Joints

Pup joints are key components in special drilling operations when specific spacing considerations are required. Our pup joints can be ordered with an 18-degree taper or square shoulder and with pressed or cast steel thread protectors.

Integral Circulating Subs or Pump-In Subs

Circulating subs are made with a pin or box connection and includes a WECO figure 1502 union. All circulating/pump-in subs are integral, one-piece design.

Integral Side-Entry Subs

All single and double side-entry subs are integral one-piece design tested to 1 1/2 times safe working pressure. Double side-entry subs are designed with a solid ID on one end made to pump through or pressure test.

Saver Subs

Saver subs are used to extend the life of the drill stem component it is made up to by taking the wear caused by multiple connections. The saver sub connection is sacrificed because it can easily be repaired or inexpensively replaced. Typically used in conjunction with a drilling rig's Kelly or Top Drive transmission.

Crossover and Bit Subs

Drilling Tools International offers cross-over subs and bit subs for any drill string connection size and function needed. Manufactured from alloy heat treated steel, our subs meet API specifications. Crossover subs adapt to different size drill pipe connections to drill collars, or drill collars to drill collars.

NOTE: Upon request, connection threads can be treated to prevent galling during make-up.

Additional Information