Vacuum Relief Valves (VRV)
The latest innovation in vacuum relief valve technology for rail tank cars is the Midland "No Step" vacuum relief valve. The new Midland "No Step" vacuum relief valve is designed to prevent the vacuum relief valve from being used as a foot valve to relieve pressure from the rail tank car. This innovative design allows the valve to only be operated in the event that vacuum conditions are reached in the car.
The new "No Step" design was created to help eliminate NAR's from vacuum relief valves that are caused by damage during loading and unloading operations. Quad seals in the vacuum relief valve provide excellent sealing in both pressure and vacuum conditions. Vacuum relief valve settings are available from 3/4 psi and higher.
A-210, 212 VRV Flyer (click HERE).
The A-212 VRV is also available as part of Midland's convenient DOT 117/117R solutions, designed to help customers meet the latest requirements for high-hazard flammable trains (HHFT) and high-hazard flammable unit trains (HHFUT).
Features & Benefits
- "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
- Stainless steel construction for better corrosion resistance
- Tamper-evident seal wire on top screws
- Pressure settings from 3/4 psi and higher
- The stem is guided in two places
- This reduces accidental cycling or "burping" of the valve due to car impact or vibration
- Gives the valve a more consistent seal and decreases the chances of pressure leaks
Models / Drawings
| Base Model | Type | Note | Connection | Material | Set-To-Discharge | AAR Approval | Drawing |
| A-207 | Threaded | w/o cap | 2-1/2" NPT | Stainless Steel (passivated) | (.75psi thru 5psi settings available) | E202130 | A-207-S |
| A-209 | Threaded | No Step | 2-1/2" NPT | Stainless Steel | (.75psi thru 5psi settings available) | E202127 | A-209-W-NS |
| A-210 | Threaded, Enhanced | Baffle, Screen | 2-1/2" NPT | Stainless Steel | (.75psi thru 5psi settings available) | E092002A | A-210-FR1 |
| A-210 | Threaded, Enhanced | Baffle, Premium Screen | 2-1/2" NPT | Stainless Steel | (.75psi thru 5psi settings available) | E092002A | A-210-FR2 |
| A-210 | Threaded, Enhanced | Screen | 2-1/2" NPT | Stainless Steel | (.75psi thru 5psi settings available) | E092002A | A-210-FR10 |
| A-210 | Threaded, Enhanced | Premium Screen | 2-1/2" NPT | Stainless Steel | (.75psi thru 5psi settings available) | E092002A | A-210-FR20 |
| A-211* | Threaded, Enhanced | Baffle, Screen | 1-1/2" NPT | Stainless Steel | (.75psi thru 5psi settings available) | E092002A | A-211-FR1 |
| A-211* | Threaded, Enhanced | Baffle, Premium Screen | 1-1/2" NPT | (.75psi thru 5psi settings available) | .75 PSI (Std.) alt. available | E092002A | A-211-FR2 |
| A-211* | Threaded, Enhanced | Screen | 1-1/2" NPT | Stainless Steel | (.75psi thru 5psi settings available) | E092002A | A-211-FR10 |
| A-211* | Threaded, Enhanced | Premium Screen | 1-1/2" NPT | Stainless Steel | (.75psi thru 5psi settings available) | E092002A | A-211-FR20 |
| A-212 | Flanged, Enhanced | Baffle, Screen | 3-7/8" B.C. | Stainless Steel | (.75psi thru 5psi settings available) | E092002A | A-212-FR1 |
| A-212 | Flanged, Enhanced | Baffle, Premium Screen | 3-7/8" B.C. | Stainless Steel | (.75psi thru 5psi settings available) | E092002A | A-212-FR2 |
| A-212 | Flanged, Enhanced | Screen | 3-7/8" B.C. | Stainless Steel | (.75psi thru 5psi settings available) | E092002A | A-212-FR10 |
| A-212 | Flanged, Enhanced | Premium Screen | 3-7/8" B.C. | Stainless Steel | (.75psi thru 5psi settings available) | E092002A | A-212-FR20 |
| A-217 | Threaded | No Step | 1-1/2" NPT | Stainless Steel | (.75psi thru 5psi settings available) | E202142 | A-217-W-NS |
| A-222 | Flanged | No Step | 3-7/8" B.C. | Stainless Steel | (.75psi thru 5psi settings available) | E202142 | A-222-W-NS |
| A-222 | Flanged | No Step, Filter | 3-7/8" B.C. | Stainless Steel | (.75psi thru 5psi settings available) | E202142 | A-222-W-NS-FR20 |
Sales Literature
-
Midland Solutions for DOT-117 Regulations Brochure
-
A 210/A 212 Vacuum Relief Valves Flyer
-
Crude Oil Railcar Brochure 2019
IOMs
-
A-541 Bottom Outlet Plug Valve IOM
-
A-547PL Bottom Outlet Plug Valve IOM
-
A-536/A-567 Bottom Outlet Plug IOM
Videos
Introduction to the A-212 Vacuum Relief Valve
Catastrophic vacuums caused while unloading are a costly threat that you can’t see coming. Midland’s A-212 Vacuum Relief Valves can stop these incidents from happening, preventing NARs and the endangerment of personnel.
Features & Benefits
- "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
- Stainless steel construction for better corrosion resistance
- Tamper-evident seal wire on top screws
- Pressure settings from 3/4 psi and higher
- The stem is guided in two places
- This reduces accidental cycling or "burping" of the valve due to car impact or vibration
- Gives the valve a more consistent seal and decreases the chances of pressure leaks
Models / Drawings
| Base Model | Type | Note | Connection | Material | Set-To-Discharge | AAR Approval | Drawing |
| A-207 | Threaded | w/o cap | 2-1/2" NPT | Stainless Steel (passivated) | (.75psi thru 5psi settings available) | E202130 | A-207-S |
| A-209 | Threaded | No Step | 2-1/2" NPT | Stainless Steel | (.75psi thru 5psi settings available) | E202127 | A-209-W-NS |
| A-210 | Threaded, Enhanced | Baffle, Screen | 2-1/2" NPT | Stainless Steel | (.75psi thru 5psi settings available) | E092002A | A-210-FR1 |
| A-210 | Threaded, Enhanced | Baffle, Premium Screen | 2-1/2" NPT | Stainless Steel | (.75psi thru 5psi settings available) | E092002A | A-210-FR2 |
| A-210 | Threaded, Enhanced | Screen | 2-1/2" NPT | Stainless Steel | (.75psi thru 5psi settings available) | E092002A | A-210-FR10 |
| A-210 | Threaded, Enhanced | Premium Screen | 2-1/2" NPT | Stainless Steel | (.75psi thru 5psi settings available) | E092002A | A-210-FR20 |
| A-211* | Threaded, Enhanced | Baffle, Screen | 1-1/2" NPT | Stainless Steel | (.75psi thru 5psi settings available) | E092002A | A-211-FR1 |
| A-211* | Threaded, Enhanced | Baffle, Premium Screen | 1-1/2" NPT | (.75psi thru 5psi settings available) | .75 PSI (Std.) alt. available | E092002A | A-211-FR2 |
| A-211* | Threaded, Enhanced | Screen | 1-1/2" NPT | Stainless Steel | (.75psi thru 5psi settings available) | E092002A | A-211-FR10 |
| A-211* | Threaded, Enhanced | Premium Screen | 1-1/2" NPT | Stainless Steel | (.75psi thru 5psi settings available) | E092002A | A-211-FR20 |
| A-212 | Flanged, Enhanced | Baffle, Screen | 3-7/8" B.C. | Stainless Steel | (.75psi thru 5psi settings available) | E092002A | A-212-FR1 |
| A-212 | Flanged, Enhanced | Baffle, Premium Screen | 3-7/8" B.C. | Stainless Steel | (.75psi thru 5psi settings available) | E092002A | A-212-FR2 |
| A-212 | Flanged, Enhanced | Screen | 3-7/8" B.C. | Stainless Steel | (.75psi thru 5psi settings available) | E092002A | A-212-FR10 |
| A-212 | Flanged, Enhanced | Premium Screen | 3-7/8" B.C. | Stainless Steel | (.75psi thru 5psi settings available) | E092002A | A-212-FR20 |
| A-217 | Threaded | No Step | 1-1/2" NPT | Stainless Steel | (.75psi thru 5psi settings available) | E202142 | A-217-W-NS |
| A-222 | Flanged | No Step | 3-7/8" B.C. | Stainless Steel | (.75psi thru 5psi settings available) | E202142 | A-222-W-NS |
| A-222 | Flanged | No Step, Filter | 3-7/8" B.C. | Stainless Steel | (.75psi thru 5psi settings available) | E202142 | A-222-W-NS-FR20 |
Sales Literature
-
Midland Solutions for DOT-117 Regulations Brochure
-
A 210/A 212 Vacuum Relief Valves Flyer
-
Crude Oil Railcar Brochure 2019
IOMs
-
A-541 Bottom Outlet Plug Valve IOM
-
A-547PL Bottom Outlet Plug Valve IOM
-
A-536/A-567 Bottom Outlet Plug IOM
Videos
Introduction to the A-212 Vacuum Relief Valve
Catastrophic vacuums caused while unloading are a costly threat that you can’t see coming. Midland’s A-212 Vacuum Relief Valves can stop these incidents from happening, preventing NARs and the endangerment of personnel.
Need help? Contact support.
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Customer Support
Reach Out to Our Customer Support Team for Prompt Assistance and Answers to Any Questions or Concerns You May Have
Technical Support
Contact Us for Technical Support on Your Projects and Resolving Any Technical Issues You Encounter
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