DMF RW-1420 Railgear Equipment

DMF RW-1420 Railgear DMF’s RW-1420 railgear is a scaled down version of our patented and very successful RW-1630 gear for large trucks. The front guidewheel assembly attaches to the frame and front axle and lifts the front wheels off the track, thus utilizing the vehicle’s front suspension. This design supports the vehicle as it was intended and helps the truck navigate curves smoothly and damp out the effects of track irregularities. The rear assembly attaches directly to the truck frame behind the rear axle spring hanger. It deploys with an articulated dual scissor action that allows the rear railgear to be moved both vertically and horizontally. This mechanism provides the “side shift” action which has made DMF gear so well known in the industry. It gives operators a greater margin for aligning the vehicle to the track which speeds and simplifies the process of getting the vehicle on rail.

RW-1420 Specifications:

FRONT:

Std: Attached to front vehicle springs.
Ground clearance retracted: 10″

REAR:

Std: Installation is to vehicle frame (bolted and clamped) below the top-of-frame line and directly behind the spring hangers.
Ground clearance retracted: 10″

BRAKES:

Optional air or hydraulic external shoe, actuated by vehicle brake pedal operation

CAPACITY:

20,000 pounds per guidewheel axle @ 20 MPH

INSTALLED WEIGHT:

Front: 1105 lbs.
Rear: 875 lbs.

AXLES:

Large 3″ 120,000 PSI yield axle with 2 1/4″ spindle
Two cast steel 14″ wheels per axle with two Timken roller bearings per wheel

SUSPENSION:

Std: Front uses front vehicle suspension
Rear acts as a rigid member between the rail and frame

GAUGE:

56 1/2″ standard (Other gauges available as an option)

PIN OFFS:

Front – Rail Mode: Design is overcenter so support is through design and welded stops
Front – Highway Mode: Mechanical safety pin-offs
Rear: Mechanical safety pin-offs are provided for rail and highway positions.

HYDRAULICS:

Typical requirements: 5 GPM @ 2,000 PSI
Pressure source: PTO/pump or a 12 VDC power unit (power unit required for brakes)
Valves: Control valves are located at each assembly
Hose and fittings: SAE 100 R1, JIC swivel ends
Cylinders: Manufactured by DMF
Manual control valves raise and lower wheels and are located near assemblies to provide visual inspection during operation.

Typical Chassis

DMF RW-1420 railgear is designed for vehicles with GVWR’s up to 33,000 lbs., such as:
- International 4300
- Freightliner M2 Business Class
- Sterling Acterra
- GMC TopKick 7500

Optional Features:
There are several options available for RW-1420 railgear. The most commonly ordered options include rail wheel brakes for improved stopping on rail, insulated wheels to prevent crossing signal actuation, rail sweeps to clear the rail of potentially damaging materials, and remote pin-offs for ease of operation. Other less common options are non-standard track gauges and slotted links for improved hi-rail performance at crossings.

Materials:
All structural members and brackets are constructed of carbon steel. The 14″ guide wheels for DMF RW-1420 railgear are machined from hardened steel castings and are fitted to high strength alloy steel axles with heavy-duty tapered roller bearings.

Installation:
Both DMF front and rear guidewheel units bolt to the truck frame using only hand tools found in any shop. They are designed to minimize the amount of space required and in many cases fit within the existing boundaries of the vehicle. The front units, however, sometimes require a bolt-on frame extension to complete the installation. Rear RW-1420 railgear mounts below the top of frame and directly behind the chassis spring hangers.

RW-1420 Brakes:
The optional RW-1420 rail brakes are an external Cobra shoe style and can be either air or hydraulically actuated. In both cases the rail brakes are applied simultaneously with the truck brakes when the operator presses the brake pedal. Both systems also have a dashboard-mounted switch that permits the operator to enable or disable the rail braking system.

Air rail brakes use a truck style air chamber to supply the clamping force. Supply pressure can come from the vehicle’s air system (preferred) or from optional skid mounted compressor. A pressure protection valve separates the railgear and the truck’s air system, preventing a failure in the rail brake system from adversely affecting truck braking.

The hydraulic rail brake option requires the installation of a hydraulic power unit to provide the braking force. When the dashboard mounted enable switch is turned on, the brake lamp signal is used as a trigger to run the pump and divert hydraulic pressure to the brakes. A built in safety circuit protects the truck’s brake lamp system as well as the hydraulic power unit from excessive run times.

Operation:
The truck is pulled onto a crossing and the wheels aligned to the tracks with attention being paid to the front. The operator then activates the hydraulic power unit by pulling the lever of the hydraulic valve to raise the railgear off of the pin-off device. The safety pins are removed and the lever pushed forward lowering the rail wheels to the track. The front gear will lift the front of the truck and go over center. The rear is operated similarly. The gear is raised to lift the weight from the pin-offs, and the pins are removed. The gear is then lowered via the two handled valve at the rear of the truck. Each spool may be operated independently to articulate the rear gear and engage the rail even if the rear wheels are not perfectly aligned. Once the rear gear is fully deployed, the pin offs are re-inserted to lock the gear in place.

Steering Wheel Lock:
The steering stop is provided with the optional railwheel brake assembly, as in the RW-1630 gear. If the unit is not equipped with optional brakes, a steering wheel lock is provided, requiring no modifications to the column.