Overview: Midland is dedicated to designing, manufacturing and distributing world-class solutions for the safe handling and the transporting of hazardous bulk products, such as crude oil & gas. Midland wants to ensure people and the environment are protected from petroleum and chemical spills, tank overfills and fugitive vapor emissions.

Midland Experience

Midland is unmatched in design expertise, product, quality, support and dedication to customer-focused service. Most of all, our products meet – in fact, they typically exceed – Association of American Railroads (AAR) regulations.

Our oil and gas experience has resulted in a manufacturing company that anticipates the energy industry’s needs and delivers superior products that help to safeguard workers and the environment. Midland’s rigid quality control standards and the utilization of statistical process controls, promises reliable product performance. Midland is ISO 9001:2008 certified and is an AAR Category F registered facility. Count on Midland to have what you want, when you want it, to meet your high-volume rail and unit car transport demands.


View Midland’s preferred fittings for crude-oil commodity cars below.







Midland has the most comprehensive valve package available for crude oil.

There are two types of bottom outlet valves available

  • Ball style
  • Plug style

Pressure Relief Valves

  • Internal Style
  • 75 psi and 165 psi valves available
  • Mounting on the plate or on a flue

Vacuum Relief Valves

  • No-step design eliminates improper cycling of the valve to release pressure
  • Unique seal design eliminates the possibility of using incorrect materials or performing improper installation
  • The stem is guided in two places:
    • Reduces accidental cycling or "burping" of the valve due to car impact or vibration
    • Gives the valve a more consistent seal and decreases the chance of pressure leaks
  • Stainless-steel construction for better corrosion resistance
  • Tamper-evident seal wire on top screws
  • Pressure settings from 3/4 psi to 3 psi

Advantage (Application-to-spec)

Midland has the most comprehensive package for crude oil.

  • Vacuum relief valves
  • High flow pressure relief valves
  • Guided and non-guided spring designs
  • Bottom outlet valves to meet the customer specification

OPW Engineered Systems components

  • Loading Arms
  • Swivels
  • Dry Disconnects
  • Couplers/Adaptors
  • ISO-Rings
  • Visi-Flos


  • Cargo Tank Truck Overfill Protection
  • Rack Monitors
  • Bottom Loading/Unloading Equipment
  • Ground Verification
  • Hatches and Openings
  • Weld Rings