Unsupported Boom Bottom Loader
Designed to provide flexible long-range operation, the heavy-duty unsupported boom type bottom loader configuration is both reliable and easy to use. A minimum of five swivel planes of rotation offer complete flexibility in making tight connections for loading and unloading rail cars and tank trucks. The outboard swivel and arm adjusts for any changes in elevation or tilting that may result as the vehicle is loaded or unloaded. The unsupported boom type loader is extremely versatile and many variations are possible. It can be equipped with dry disconnect coupler, union, quick coupling, or other customer specified end fitting to make connections on the side, at the rear, or underneath the vehicle. The intermediate swivel is often 2” – 6” sizes available inverted to achieve the low profile and clearances needed to connect to the underside of a rail car.
Typically installed at or near ground level, arms of varying lengths can be mounted on staggered risers to achieve crossover and neat compact storage of multiple arms in a confined space.
- 2” – 6” sizes available
- Carbon Steel, Stainless Steel and Aluminum options
- Ideal for Railcar Unloading applications
- Fully customizable
Accessories
Heating – Loading Arms can be fully or partially jacketed for efficient handling of asphalt, molten sulfur, waxes, resins and other products that are highly viscous or tend to solidify at ambient temperatures. Click here for more information on OPW Heated Loading Solutions.
Loading Arm Insulation – OPW can provide a Custom Insulation Package designed specifically for your loading arm. Unlike field-applied insulation, these packages are completely removable and reusable, making them the ideal solution for loading arm use. Click here to view Loading Arm Insulation Specifications.
Grounding/Bonding – Suggested for many top/splash loading applications. Available as an option on all Loading Arm designs.
Protects your equipment, piping and personnel in the event of an unintended pull-away. A consideration whenever you are making a tight connection to a truck or railcar.
Quick & Dry Disconnect Couplings
With OPW, you have many options at your disposal for your loading arm termination connections. From the original quick-disconnect Kamlok® coupling to our Epsilon™ dry disconnect coupling, we have a coupling to meet your needs.
Commonly used for loading Petroleum products, OPW provides several options for loading your Petroleum transports.
6400 Series Horizontal Valve – OPW Loading Valves are designed to shut off flow without causing shock in the pipeline.
- Adjustable closure rate
- 3” & 4” sizes, Aluminum Construction
- TTMA Flanged connections
- Ball Valves (per application/specification)
Pneumatic Counterbalancing – An alternative to conventional spring balanced loading arm, pneumatics provide the ultimate in loading arm design.
Features & Benefits
- Easy to operate/maneuver
- Eliminates cumbersome hose
- Low Profile with long reach, ideal for railcar unloading
- Accommodates changes in elevation
- Can be safely stored to provide for safe clearance of vehicles
- Easy to connect under the vehicle
- Very flexible to compensate for vehicle misplacement
- Scissor-back storage means no wasted space
- Compact storage, can be stored in ‘jack-knife’ position
Library
All OPW Loading Arms can be customized to fit your specific application requirements. We do offer a series of Standard/ optimized solutions that are commonly specified. These optimized selections can be expedited to meet faster delivery requirements. 3” Bottom loading Arm Ductile Iron/Carbon Steel/ Aluminum Construction 42” x 66” G32FNV-3 Same as above in 4” (G32FNV-4)
Technical
Click on the title below to view the technical information.
Loading Arm Velocities What size pipe do I need?
| Velocity in ft/sec. | ||||
GPM | 2" | 3" | 4" | 6" |
100 | 9.6 |
|
|
|
125 | 12 |
|
|
|
150 | 14.3 |
|
|
|
175 | 16.8 |
|
|
|
200 | 19.1 | 8.7 |
|
|
225 | 21.5 | 9.8 |
|
|
250 | 23.9 | 10.8 |
|
|
300 |
| 13 | 7.5 |
|
350 |
| 15.2 | 8.8 |
|
400 |
| 17.4 | 10.1 |
|
450 |
| 19.6 | 11.4 |
|
500 |
| 21.7 | 12.6 | 5.6 |
550 |
| 23.9 | 13.8 | 6.1 |
600 |
|
| 15.1 | 6.6 |
650 |
|
| 16.4 | 7.2 |
700 |
|
| 17.6 | 7.8 |
750 |
|
| 18.9 | 8.3 |
800 |
|
| 20.2 | 8.9 |
900 |
|
| 22.7 | 10 |
1000 |
|
|
| 11.1 |
1200 |
|
|
| 13.3 |
1300 |
|
|
| 14.4 |
1400 |
|
|
| 15.6 |
1500 |
|
|
| 16.7 |
1600 |
|
|
| 17.8 |
1700 |
|
|
| 18.9 |
1800 |
|
|
| 20 |
Velocities above 15 ft./sec. (4.6 m/sec.) are generally not recommended - Bold are recommended.
| Velocity in m/sec. | ||||
L/min. | 2" | 3" | 4" | 6" |
400 | 3.1 |
|
|
|
600 | 4.6 | 2.1 |
|
|
800 | 6.1 | 2.8 |
|
|
1000 | 7.7 | 3.5 | 2 |
|
1250 | 9.6 | 4.4 | 2.5 |
|
1500 |
| 5.2 | 3 |
|
1750 |
| 6.1 | 3.5 |
|
2000 |
| 7 | 4 |
|
2250 |
| 7.9 | 4.5 | 2 |
2500 |
| 8.7 | 5.1 | 2.2 |
2750 |
|
| 5.6 | 2.4 |
3000 |
|
| 6.1 | 2.6 |
3250 |
|
| 6.6 | 2.9 |
3500 |
|
| 7.1 | 3.1 |
3750 |
|
| 7.6 | 3.3 |
4000 |
|
| 8.1 | 3.6 |
4500 |
|
| 9.1 | 4 |
5000 |
|
|
| 4.5 |
5500 |
|
|
| 4.9 |
6000 |
|
|
| 5.3 |
6500 |
|
|
| 5.8 |
7000 |
|
|
| 6.2 |
Loading Arm Swivel/Spring Dimensions
How much clearance will my loading arm require?
Coming soon.
Loading Arm Configurations
Videos
OPW Loading Systems
The transfer of volatile, valuable, potentially toxic fluids requires highly engineered loading arms, couplers and swivels. OPW Engineered Systems is the global leader in the design and manufacture of products that transfer fluids SAFER, CLEANER, FASTER.
Success Story: SI Group
This success story demonstrates how the SI Group Manufacturing prefers OPW Engineered System's Drylock Disconnect Couplers and Adaptors for their outstanding safety features, with virtually no fluid loss and no exposure.
Drylok™ is designed to safely transfer hazardous corrosive, volatile liquids such as acids, solvents and petrochemicals. An interlocking handle averts accidental spills by preventing uncoupling while the valve is open. And, the unit's flat face minimizes fluid loss, further reducing exposure to risk during operation. Drylok™ is ideal for all kinds of hazardous fluids where product loss is a problem, such as high-pressure lines, high flow rates, slurries, and gases.
Downloads
-
Loading-Arm-Design-Form
-
Loading-Arm-configurations
-
3000 Series Installation Operations Manual
-
8000 Series Endura Installation Operations Manual
-
790 Counterbalance Installation Operations Manual
-
890 Series Torsion Spring Counterbalance Installation Operations Manual
-
Loading Arms Installation Operations Manual
-
Terminal Solutions Brochure
-
Terminal Survey Form
-
Folleto Soluciones Totales Para Terminales (En Español)
-
Hoja de Datos Estándar para Carga por Debajo - Español
-
Bottom Unloading Rail Layout Form
-
Tank Truck Bottom Loading Layout Form
Accessories
Heating – Loading Arms can be fully or partially jacketed for efficient handling of asphalt, molten sulfur, waxes, resins and other products that are highly viscous or tend to solidify at ambient temperatures. Click here for more information on OPW Heated Loading Solutions.
Loading Arm Insulation – OPW can provide a Custom Insulation Package designed specifically for your loading arm. Unlike field-applied insulation, these packages are completely removable and reusable, making them the ideal solution for loading arm use. Click here to view Loading Arm Insulation Specifications.
Grounding/Bonding – Suggested for many top/splash loading applications. Available as an option on all Loading Arm designs.
Protects your equipment, piping and personnel in the event of an unintended pull-away. A consideration whenever you are making a tight connection to a truck or railcar.
Quick & Dry Disconnect Couplings
With OPW, you have many options at your disposal for your loading arm termination connections. From the original quick-disconnect Kamlok® coupling to our Epsilon™ dry disconnect coupling, we have a coupling to meet your needs.
Commonly used for loading Petroleum products, OPW provides several options for loading your Petroleum transports.
6400 Series Horizontal Valve – OPW Loading Valves are designed to shut off flow without causing shock in the pipeline.
- Adjustable closure rate
- 3” & 4” sizes, Aluminum Construction
- TTMA Flanged connections
- Ball Valves (per application/specification)
Pneumatic Counterbalancing – An alternative to conventional spring balanced loading arm, pneumatics provide the ultimate in loading arm design.
Features & Benefits
- Easy to operate/maneuver
- Eliminates cumbersome hose
- Low Profile with long reach, ideal for railcar unloading
- Accommodates changes in elevation
- Can be safely stored to provide for safe clearance of vehicles
- Easy to connect under the vehicle
- Very flexible to compensate for vehicle misplacement
- Scissor-back storage means no wasted space
- Compact storage, can be stored in ‘jack-knife’ position
Library
All OPW Loading Arms can be customized to fit your specific application requirements. We do offer a series of Standard/ optimized solutions that are commonly specified. These optimized selections can be expedited to meet faster delivery requirements. 3” Bottom loading Arm Ductile Iron/Carbon Steel/ Aluminum Construction 42” x 66” G32FNV-3 Same as above in 4” (G32FNV-4)
Technical
Click on the title below to view the technical information.
Loading Arm Velocities What size pipe do I need?
| Velocity in ft/sec. | ||||
GPM | 2" | 3" | 4" | 6" |
100 | 9.6 |
|
|
|
125 | 12 |
|
|
|
150 | 14.3 |
|
|
|
175 | 16.8 |
|
|
|
200 | 19.1 | 8.7 |
|
|
225 | 21.5 | 9.8 |
|
|
250 | 23.9 | 10.8 |
|
|
300 |
| 13 | 7.5 |
|
350 |
| 15.2 | 8.8 |
|
400 |
| 17.4 | 10.1 |
|
450 |
| 19.6 | 11.4 |
|
500 |
| 21.7 | 12.6 | 5.6 |
550 |
| 23.9 | 13.8 | 6.1 |
600 |
|
| 15.1 | 6.6 |
650 |
|
| 16.4 | 7.2 |
700 |
|
| 17.6 | 7.8 |
750 |
|
| 18.9 | 8.3 |
800 |
|
| 20.2 | 8.9 |
900 |
|
| 22.7 | 10 |
1000 |
|
|
| 11.1 |
1200 |
|
|
| 13.3 |
1300 |
|
|
| 14.4 |
1400 |
|
|
| 15.6 |
1500 |
|
|
| 16.7 |
1600 |
|
|
| 17.8 |
1700 |
|
|
| 18.9 |
1800 |
|
|
| 20 |
Velocities above 15 ft./sec. (4.6 m/sec.) are generally not recommended - Bold are recommended.
| Velocity in m/sec. | ||||
L/min. | 2" | 3" | 4" | 6" |
400 | 3.1 |
|
|
|
600 | 4.6 | 2.1 |
|
|
800 | 6.1 | 2.8 |
|
|
1000 | 7.7 | 3.5 | 2 |
|
1250 | 9.6 | 4.4 | 2.5 |
|
1500 |
| 5.2 | 3 |
|
1750 |
| 6.1 | 3.5 |
|
2000 |
| 7 | 4 |
|
2250 |
| 7.9 | 4.5 | 2 |
2500 |
| 8.7 | 5.1 | 2.2 |
2750 |
|
| 5.6 | 2.4 |
3000 |
|
| 6.1 | 2.6 |
3250 |
|
| 6.6 | 2.9 |
3500 |
|
| 7.1 | 3.1 |
3750 |
|
| 7.6 | 3.3 |
4000 |
|
| 8.1 | 3.6 |
4500 |
|
| 9.1 | 4 |
5000 |
|
|
| 4.5 |
5500 |
|
|
| 4.9 |
6000 |
|
|
| 5.3 |
6500 |
|
|
| 5.8 |
7000 |
|
|
| 6.2 |
Loading Arm Swivel/Spring Dimensions
How much clearance will my loading arm require?
Coming soon.
Loading Arm Configurations
Videos
OPW Loading Systems
The transfer of volatile, valuable, potentially toxic fluids requires highly engineered loading arms, couplers and swivels. OPW Engineered Systems is the global leader in the design and manufacture of products that transfer fluids SAFER, CLEANER, FASTER.
Success Story: SI Group
This success story demonstrates how the SI Group Manufacturing prefers OPW Engineered System's Drylock Disconnect Couplers and Adaptors for their outstanding safety features, with virtually no fluid loss and no exposure.
Drylok™ is designed to safely transfer hazardous corrosive, volatile liquids such as acids, solvents and petrochemicals. An interlocking handle averts accidental spills by preventing uncoupling while the valve is open. And, the unit's flat face minimizes fluid loss, further reducing exposure to risk during operation. Drylok™ is ideal for all kinds of hazardous fluids where product loss is a problem, such as high-pressure lines, high flow rates, slurries, and gases.
Downloads
-
Loading-Arm-Design-Form
-
Loading-Arm-configurations
-
3000 Series Installation Operations Manual
-
8000 Series Endura Installation Operations Manual
-
790 Counterbalance Installation Operations Manual
-
890 Series Torsion Spring Counterbalance Installation Operations Manual
-
Loading Arms Installation Operations Manual
-
Terminal Solutions Brochure
-
Terminal Survey Form
-
Folleto Soluciones Totales Para Terminales (En Español)
-
Hoja de Datos Estándar para Carga por Debajo - Español
-
Bottom Unloading Rail Layout Form
-
Tank Truck Bottom Loading Layout Form
OPW CORPORATE HEADQUARTERS
9393 Princeton-Glendale Road
Hamilton, Ohio, USA 45011
Phone: (800) 547-9393
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