DBT leads charge in circuit design

THE industry-wide trend for continually increasing shearer speeds combined with extended face lengths has placed high demands on face hydraulics. Increased flow rates have led to higher pressure drops, necessitating careful design of the face layout and exact shield set pressures to maintain sufficient roof support.
DBT leads charge in circuit design DBT leads charge in circuit design DBT leads charge in circuit design DBT leads charge in circuit design DBT leads charge in circuit design

DBT’s Franz-Heinrich Suilmann uses Automation Studio to calculate complete underground face layouts

Angie Tomlinson

Published in May 2005 American Longwall Magazine

To overcome these challenges and provide customers with a complete mining system design, original equipment manufacturer DBT has employed the software program Automation Studio from Canadian outfit Famic Technologies. Automation Studio is a circuit design, simulation and project documentation software for fluid power systems. Used by engineers, trainers, and service and maintenance personnel, the software can be applied in design, training and troubleshooting of hydraulics, pneumatics and electrical control systems.

To allow DBT to use the program to lay out and calculate complete underground face layouts, the software had to be programmed to DBT’s unique needs. To begin with, DBT’s specific hydraulic components were entered into the software and the fluid parameters modified to simulate water hydraulic characteristics (Automation Studio's standard fluid had previously been mineral-based hydraulic oil).

Once a circuit is drawn, the simulation mode shows valves shifting positions, cylinders moving, and the status of switches changing. Fluid lines change color to indicate fluid pressure status, and plotter functions can be added to monitor variables such as speed, acceleration, flow and position, display trends, and store numerical data. Circuit components can be sized for more accurate results. Automation Studio also includes simulation models for servo and servo-proportional valves, variable displacement pumps, proportional pressure regulators, and flow controls.

According to DBT’s Franz-Heinrich Suilmann, who was intimately involved with Famic in the development of the software, DBT chose Automation Studio as the new design tool for hydraulic face layouts for its flexibility of circuit design.

“A lot of customers ask for a complete design process where you must show optional layouts by changing the hosing and piping of the circuit to find the best solution for cost, space and performance of the circuit. To be able to easily modify and change the circuit design makes Automation Studio the preferred tool for DBT's system design,” he said.

The software also allows for simulation of individual components used in the underground circuit and adaptation of its hydraulic characteristics. This has allowed DBT to achieve a very close correlation between the simulated circuit and the real circuit. As circuit design evolves underground, the simulation can be updated to ensure accurate results. “Of course, underground testing and lab testing of components is necessary in order to create the hydraulic parameters used for building the circuits,” Suilmann said.

Since DBT began using the software a year ago, design integrity has already been tested underground. “We already have seen how, through the use of Automation Studio, different layouts could be evaluated in their complexity that we were not able to do before. This is a big step forward in circuit design, since you can imagine due to the enormous size of an underground circuit that it can not easily be changed once it is installed underground. The process of optimization has become extremely efficient due to the use of the new software,” Suilmann said.

In addition to the face layouts, the software has also improved and assisted in shield design. The complete shield circuit can be simulated, and, according to Suilmann, can be further improved. “Project work as creation of drawings, parts lists, and user-defined libraries of our components, is another big plus which DBT will benefit from in the future,” he said.