Sand Control Completion Accessories

In today’s environment, untimely interventions disrupt production and can impact well economics. Maintaining optimal well performance begins by selecting the proper screen design, placement technique, and completion accessories. M.I.’s portfolio of downhole components and accessories give operators the ability to customize their completion assembly based on well parameters and reservoir characteristics, reducing the need for unplanned interventions and enhancing completion longevity.

Hook-Up Nipple (H.U.N.) & Back-Off Sub


H.U.N. & Back-Off Sub

The M.I. Hook-Up Nipple and Back-Off Sub are dual purpose components in the gravel pack assembly. Each serve as the release point for the completion service tool, and as the landing nipple for the Mitchell “L” Packer and Seal Stack Overshot. The standard H.U.N. is offered in 6 ft. and 8 ft. lengths, while the Back-Off Sub is typically 0.5 – 1 ft. in length. Both components have a left-handed square ACME threads machined into the top sub, allowing for a right-hand rotational release. Back-Off Subs are offered in low-alloy steel and 304L SS, and are used in conjunction with the M.I. “L” Isolation Packer. Our M.I. Hook-Up Nipples are offered in a polished 304L SS material and are used with the M.I. Seal Stack Overshot.

Completion Packers & Production Overshots


Mitchell Type "L" Liner Packer

The M.I. Type “L” Isolation Packer is a tubing conveyed, mechanically set retrievable packer used in conjunction with gravel pack completions. The “L” Packer features a large internal by-pass that reduces swabbing when running or retrieving. The packer is designed to isolate the lower gravel pack completion by restricting annular flow, forcing all production through the screen. It is equipped with a lower seal extension that stings over our M.I. Hook-Up Nipple and/or Back-Off Sub.


  • Field proven, robust design
  • Large internal by-pass
  • Retrievable (re-dress capabilities)
  • Shear off, single trip option available
  • Carbon steel and coated options available
Drawing of side view cross-section of a pipe

Mitchell Seal Stack Overshot

The M.I. Seal Stack Production Overshot can be run under a production or permanent packer, and is designed to seal over our M.I. Hook-Up Nipple. The lower seal extension houses dual opposing molded seal sets that control pressure from above and below the seals. The overshot has a standard 6 ft. bore length to accommodate tubing movement while setting the packer and landing the production tubing at surface.


  • Easy to install
  • Facilitates packer setting and tubing placement
  • Retrievable (re-dress capabilities)
  • Dual opposing molded seal sets
  • Carbon steel and coated options available
Drawing of side view cross-section of a pipe

AS1-X Production Packer

The AS1-X Double-Grip Packer is a mechanically set retrievable packer used in a wide range of production applications. When utilized in sand control completions, a production overshot is run below the AS1-X Packer as a seal extension. The overshot is landed on the hook-up nipple and the packer is set, either in tension or compression. The AS1-X packer can be run on the bottom of the production tubing, or can be equipped with a stigner and on/off tool for tubing detachment.


  • Can be set in tension for shallow well applications
  • Can be left in tension, compression, or neutral
  • 1/4 turn right-hand set, 1/4 turn right-hand release
  • Differential pressures up to 7,000 psi
  • Can be equipped with on/off mechanism (production assembly/tubing are independent of lower completion)

Model MR-3D Completion Packer

The MR-3D Double-Grip Packer is a mechanically set retrievable packer used in completion, stimulation, testing, and production applications. For gravel pack operations, the packer is equipped with a clutch joint/circulating kit and is used as a service tool. In production applications, an overshot is run below the packer as a seal extension and the packer is set with the upper production assembly.


  • Field proven design
  • Large internal by-pass flow area
  • 1/4 turn right-hand set, straight pull release
  • Differential pressures up to 5,000 psi
  • Suitable for cased hole gravel packs, open hole gravel packs, or HRWP
Drawing of side view cross-section of a pipe

Single and Dual Bore Permanent Packers (Sump Packers)

Both the single and dual seal bore packers can be used for single or multiple zone completions. Each packer may be set hydraulically or on wireline, and are available in a variety of seal bore materials and elastomers.

Seal bore packers can be used as a gravel pack base, or in the upper completion assembly. Each packer is supported by a complete line of tubing seal accessories and elastomers.


  • Hydraulic, electric line, or mechancial set
  • Keyed components for milling operations
  • Large packer bore

Seal Assemblies

Drawing of side view cross-section of a pipe

Locator Subs, Snap Latches, and Anchor Latches

Seal assemblies are used to land or lock into the polished bore of a packer, creating a leakproof seal. Locator subs are used in installations that require floating seals, allowing for slight tubing movement during expansion and contraction. Snap latch seal assemblies latch into the packer and provide a mechanical indication that the seal assembly is positioned properly in the packer bore. The sanp latch can be removed with a straight pull of 10-12K over tubing weight. The anchor latch assembly latches into the packer bore just like the snap latch, but is removed with 8-10 right-hand rotations. Each of these seal assemblies can be provided with mule shoe guides on bottom, and various length seal units depending on the application.

When sump packers are used in the gravel pack completion design, a seal assembly is required to prevent gravel pack sand from leaking past the packer. In the case of a multizone gravel pack completion, the seal assembly also provides zonal isolation.

Other Completion Accessories


Wireline Entry Guides (WLEG)

The wireline entry guide has an internal bevel on the bottom of the tool that guides wireline or slickline tools back into the tubing. The re-entry guide can be run under various packers, but is most commonly utilized under the lower permanent packer in a gravel pack completion.

Safety Joints

Safety Joints

The safety joint allows for an emergency release of the tubing string in completions with expected retrieval challenges. The joint is typically used below the completion packer, or in between packers in dual completions. Safety joints are available in straight pull shear release, rotational release, and swivel shear release. These safety joints are keyed so torque through the tool does not load the shear screws.

Drawing of side view cross-section of a pipe

Profile Nipples

Profile nipples are ‘no-go’ devices with a reduced bore smaller than the tubing I.D. The flow control plug is lowered down the tubing via e-line or slickline and engages the internal profile of the nipple. Profile nipples can be used in multizone gravel pack completions to provide flow control and zonal isolation.

Sand Control Solutions
Wedge Wire Screen Products
Industrial Blasting & Coating

Contact us at (281) 576-5007