MRRM is a tool to create a supply and demand, traffic based railroad workload and the necessary railroad information to move ladings (goods) from Shippers to Consignees. There are two major components: Industry Activity and Railroad Activity.
The Industry Activity component specifies the commodity workload to be imposed on your railroad and other railroads that interchange with your railroad. The components of Industry activity are: Lading (Commodities) supported by your railroad, shipping and receiving activity by industries that use your railroad, shipper production and consignee consumption specifications, pairing buyers and sellers and balancing these, time interval based buyer order generation, seller shipment generation, railroad back office shipment routing and car assignment, and car ordering from foreign yards, if required.
The Lading table lists the types of commodities that your railroad supports. For each commodity, you specify the AAR car type used to carry that commodity on your railroad. Lading names are arbitrary if you do not do business with other layouts carrying the same commodity otherwise agreement is needed for multi-layout operations. If you have, for example, a number of boxcars that are limited to handling a specific type of goods, say food, then you can create an AAR+ subcode, say XMF, to stop this car from being automatically applied to general merchandise hauling requirements.
For each Industry you serve, you must specify which commodities they buy and which commodities they sell. For each commodity you must specify the Stop where the commodity is picked up if it is a commodity the industry sells or the Stop where the commodity will be set out if the industry buys the commodity. An Industry may have an arbitrary number of commodities bought and sold
For each commodity that an Industry sells, its shipper production must be specified. This specification includes the average frequency of commodity batches produced and the average number of carloads produced per batch. The desired number of empty cars to be maintained at the stop must also be specified, if any.
For each commodity that an Industry buys, its consignee consumption must be specified. This specification includes the average frequency of commodity batches consumed and the average number of carloads ordered per batch ordered.
You may specify multiple buyers and sellers of any commodity. The buyer may or may not be on your layout. Ditto for the seller. MRRM will stochastically match a seller for each buyer order. A tool facilitates balancing overall buy-sell activity per commodity.
An Order is placed by/for a Consignee. MRRM operates on Greenwich Mean Time. For each Industry activity, MRRM maintains the time when a re-order event must occur for each commodity bought. The time between re-orders can be constant or a random variable within a specified range. When the time to re-order occurs, the number of carloads to be ordered may be a constant or a random variable within a specified range. The weight of the carloads is also computed.
The Seller is the Shipper. Within an average of one half hour of the order generation event, the Shipper issues a shipment request to the 'railroad back office' software (an automated forwarding process).
The Railroad component supports the Back Office as well as Train and Yard activities.
The railroad back office receives the Shipper's request for the commodity to be picked up at its specified location and set out at the Consignee's specified location. This legal document of temporary ownership is called a Bill of Lading (BoL). The BoL functions as a receipt, as evidence of or containing the contract of carriage and as a document of title.
The railroad back office then manages the following actions for current BoLs:
BoL performance involves Car Ordering, Shipment Routing and Car Assignment, Waybills, Schedules, Manifest, Hostler Consist Orders, Yardmaster Switchlists, and Conductor Switchlists.
If the shipment comprises multiple cars and some are available and some are not, the shipment is divided into two shipments and each are handled as appropriate.
If there are no cars of the needed type at the Industry or at the yard serving the industry when the shipment occurs, MRRM will order the car from another yard in the same division or from another car in a foreign division. If the car is found, its route will be created as a separate shipment activity. The awaiting shipment will wait for the car to arrive and be loaded before a train is scheduled to come and get the car.
The next hour after the seller's shipment 'paperwork' arrives at the railroad back office, each car needed for the shipment is assigned to the shipment. A route is then created from getting the empties needed by the shipper, if any, to the shipper to picking up the cars and bringing them back to the yard serving the seller and so forth until the consignees has emptied the loads and they are returned where they belong. Many trains may be involved with any shipper/consignee transaction. Empty management can involve multiple moves initially and when the consignee is done with the cars.
A waybill is an internal railroad bill of lading with pick up and set out stops. Waybills are created automatically for your 2nd, 3rd and 4th Class Freight traffic if you use the semi-automatic traffic generator described on another web page. Waybills may be manually created for any lading and class use.
For freight operations on your railroad, you can either manually create waybills for the car movements and build a locked train to run time and time again. Or, you can semi-automatically create shipments between buyers and sellers together with the semi-automatic generation of waybills, manifests, schedules, and switchlists and then run the train once. The Industry Activity window supports the semi-automatic generation freight operations mode
A Schedule is a sequence of stops for a train. When the arrival and departure times for each stop for a specific train number and day are specified, we create a Train Schedule.
In order to run a train with MRRM, a manifest is required. The manifest for a train comprises the train number, its schedule and the list of waybills representing the cargo to be carried by the train.
Before a train with manifest can run, the assigned consist power must be brought to the staging area in the departure yard. The Hostler is the agent of the Roundhouse foreman that brings the locomotive power to the yard prior to the train's initial departure. The Hostler return the consist power to its homeyard after the train run is completed.
The Yardmaster assembles the consist for the Conductor prior to initial departure. The Wheel reports identify the cars that are expected to depart from or arrive at the yard throughout the day. Together with a copy of the Train Manifest's Conductor Switchlist, the Yardmaster can make the train or break it down as appropriate. Interchanges are special yards shared between two railroads. Interchange Departures and Arrivals must also be managed by a Yardmaster.
The Conductor is responsible for a Train. The Engineer drives the train. The Conductor Switchlist defines the pickups and setouts to be performed at each stop on the train schedule. The Conductor gets the switchlist from the Dispatcher pending approval of the Yardmaster to embark. The Engineer gets a copy of this switchlist.
Completing all movements, needed for the first two shipments in the video above, requires 10 trains in a twelve hour period .
Three windows are collated in the following image: manifests, shipments and train rules windows. Note that in addition to the six locals run from Reading, Philadelphia or Erie yards, four way freights were needed to move empty or full cars between these three yards.
Notice that in the shipments window, two shipments were created to move empty cars back to their respective home yards
The train rules for the Philly local chosen is shown in the Train Rules window.
There are 84 industries moving commodities (ladings) in railroad cars between producers and consumers on our railroad - 12 which are reachable via one of our four interchanges. Our current Industry activity moves 40 types of Lading. These are our Commodity Buying and Selling Industries.
To keep up with the total industry production and consumption of these commodities, our simulation predicts that the railroad must move about 120 cars per day (each requiring a Waybill). These moves require about 20 trains of about six cars per train.
Each train requires a manifest with the waybills for each car, a schedule of train stops and a switchlist specifying the pickups and setouts at each stop.
A Session Timetable provides a spreadsheet of stop activity for all trains run in a given day.