Special Subs


DRIVE SUBS : These special subs known as Drive Subs provide the crossover connection between drill pipe string and the washover string. Each of these subs are machined from high-grade alloy steel. They are usually machined with “Box-Up” configuration as per customer’s specification and a “Pin-Down” connection that matches customer’s washover string connection. A fishing neck is also provided for ease of handling as per customer requirements.

Ordering Instructions:

When ordering or requesting quotations on Drive Subs, please specify:

  1. Top Box Connection.
  2. Lower Pin Connection (Washover pipe OD and weight.)
  3. Overall Length of Drive Sub.
  4. Fishing neck Dia. and length.


STOP SUBS :These subs are designed for use as a mandrel accessory of the Grapple Releasing Spear. They provide a shoulder or stop surface which lands on top of the fish thus preventing the spear from entering the fish too deeply. This feature helps the operator of the Grapple Releasing Spear to determine the actual depth of the fish.

Ordering Instructions:

When ordering or requesting quotations on Stop Subs, please specify:

  1. OD of Stop Sub Body.
  2. Length from Stop to Thread Connection.
  3. Top and Bottom Connections desired.
  4. OD of Stop Ring.
  5. OD on Stop Sub shoulder with which Stop Ring is used.
  6. Type of Stop Ring – Threaded or Sliding


TRIPLE CONENCTION SUBS :These subs consists of three connections – a washpipe connection and two drillpipe connections. The position of the washpipe connection is directly above the drill pipe connection at one end. Customer has the option to decide if a fishing neck is needed and the position of the washpipe connection.  

Ordering Instructions:

When ordering or requesting quotations on Triple Connection Subs, please specify:

  1. Top and Bottom Connections.
  2. Length
  3. Fishing Neck Dia. and Length.
  4. Type of Washpipe Connection required
  5. Position of Washpipe Connection – Above Top end Box Connection or at centre of Sub.