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Industrial Screen & Maintenance manufactures downhole subs and crossover subs for use in downhole drilling operations.

Crossover Subs

Downhole Subs and Crossover subs are a basic tubular component used in the downhole drilling operations.  Its primary purpose is to enable two components with different connections to thread together.  A variety of drilling subs such as circulating subs, lifiting subs, and saver subs and are available for all different types of applications, like protecting high value drill stem components, fluid circulation, preventing flowback and lifting or transporting. There are a wide array of shapes and sizes available for downhole subs, all custom configurations are available upon request.  ISM Manufacturers all downhole drilling subs with solid heat-treated alloy 4140/4145 steel to meet API Specifications. 

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Sub Assemblies and Configurations

  • Lifting Subs- Lift Subs are offered as a conventional design in a variety of sizes to provide ease of handling long products or heavy downhole 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
  • Crossover Subs- Cross-over subs and bit subs can be made for any drill string connection size and function needed. Manufactured from heat treated alloy steel and machined to meet API specifications. Designed solely to enable two components with different connections to thread together.
  • Saver Subs- Saver subs are used to extend the life of the drill stem component it is threaded up to by taking the wear caused by multiple connections. The saver sub is used a sacrificial connection sub because it can easily be repaired and is a low-cost replacement. Saver Subs are typically used in conjunction with a drilling rig's Kelly or Top Drive transmission.
  • Float Subs- Float Subs are used to house the float valve and provide 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.
  • Custom Application Subs- ISM can manufacture any type and configuration to meet your drill stem configurations.
  • Other Sub Names and Configurations Available; Circulating Sub, UBHO Mule Shoe Sub, Pump in Sub, Pup Joint Sub and many more. 

ISM offers a variety of subs in AISI 4140/4145 heat-treated steel and non-magnetic stainless. Virtually any type of sub can be manufactured in-house to customer specifications.

Industrial Screen & Maintenance offers lifting subs, crossover subs, saver subs, float subs, custom application subs and more!

Contact Us

Industrial Screen and Maintenance (ISM) has two locations, the original Machine Shop in Casper, WY since 1969 and a full-service Machine Shop in Grand Junction, CO established 2005. Both facilities have CNC lathes, mills and manual machines with highly trained machinists, welders, and fabricators with decades of experience. ISM carries a large inventory of all common high yield alloys, stainless steel, carbon steel, aluminum, brass, bronze, and copper. This gives us the ability to provide fast lead times, saving you valuable downtime. We differentiate ourselves by providing the most rapid response possible to quotes and inquires. 

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Why Work With ISM

Industrial Screen and Maintenance (ISM) is a Crossover Subs Manufacturer and has worked with many of the Drilling Companies for manufacturing Crossover Subs and many other downhole subs used in the drilling operations.  For over 50 years ISM has proudly serviced the Oil & Gas community with High Quality CNC Machining and Machine Shop services specializing in all tapered, shouldered rotary connections including API, Grand Prideco and VAM.  Offering on stop for all services, design, manufacturing, inspections, and tubular thread repair services.  Full in-house Quality Control ensures that each threaded connection leaves ISM meeting all API Specifications.  

We know you cannot afford downtime, Quality and Service are number one at ISM.  With two locations ready to serve you, Casper, WY, and Grand Junction, CO with in-stock high yield alloys ready to manufacture or service your Crossover Subs to keep your drilling operations running.  

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750 East F Street
Casper, WY 82601

307 234 3547


2285 Logos Court
Grand Junction, CO 81505

970 245 4020