OPW Engineered Systems
Unsupported Boom Bottom Loader

Loading Arm Configurations

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

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

Loading Arm Velocities What size pipe do I need?

Velocity in ft/sec.						Velocity in m/sec.
GPM	2"	3"	4"	6"		L/min.	2"	3"	4"	6"
100	9.6					400	3.1
125	12					600	4.6	2.1
150	14.3					800	6.1	2.8
175	16.8					1000	7.7	3.5	2
200	19.1	8.7				1250	9.6	4.4	2.5
225	21.5	9.8				1500		5.2	3
250	23.9	10.8				1750		6.1	3.5
300		13	7.5			2000		7	4
350		15.2	8.8			2250		7.9	4.5	2
400		17.4	10.1			2500		8.7	5.1	2.2
450		19.6	11.4			2750			5.6	2.4
500		21.7	12.6	5.6		3000			6.1	2.6
550		23.9	13.8	6.1		3250			6.6	2.9
600			15.1	6.6		3500			7.1	3.1
650			16.4	7.2		3750			7.6	3.3
700			17.6	7.8		4000			8.1	3.6
750			18.9	8.3		4500			9.1	4
800			20.2	8.9		5000				4.5
900			22.7	10		5500				4.9
1000				11.1		6000				5.3
1200				13.3		6500				5.8
1300				14.4		7000				6.2
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.

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.
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.

Grounding/Bonding – Suggested for many top/splash loading applications. Available as an option on all Loading Arm designs. 
Electronic Ground Verification The Civacon model 8030 Ground Verification Monitor is compatible with today’s transport ground systems. The monitor is equipped to provide a permissive signal to allow load rack operation and, if ground is lost, to indicate a non-permissive signal and shut down the loading operation.

Safety Breakaway Coupling   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.
API Bottom Loading Couplers Commonly used for loading Petroleum products, OPW provides several options for loading your Petroleum transports.

Loading Valves

• 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.