Sdrg controls uses automation direct equipment to implement new friction drillpipe processing line

A Success Story SDRG Controls Uses Automation Direct Equipment to Implement New Friction Drillpipe Processing Line SDRG Controls (www.SDRG.com) is a control systems integrator in Houston, Texas that recently helped Superior Drillpipe implement a new drillpipe processing line that friction welds tool joints to drillpipe and conditions the pipe to meet tough drilling customer requirements. The line is controlled by an Automation Direct DirectLogic 405 PLC and Cmore touch panel HMI. Superior Drillpipe needed to tie a wide variety of equipment stations and functions into a seamlessly flowing system that kept costs low while efficiently delivering the functionality necessary to produce high quality drilling pipe products. SDRG Controls first worked with Superior to define the items necessary to control and the operating sequence that best met their needs. SDRG Controls selected Automation Direct equipment to serve as the heart of the system due to their high performance, cost effective products. The DL405 PLC was selected due to its modular flexibility, wide I/O support, low costs, and familiar, but powerful programming and operating capabilities.

Each station on the line was configured somewhat independently, with many pushbutton stations that allowed the operator flexible control and the ability to control the line pace at a rate that allowed proper attention to special detail when appropriate. Pushbutton stations were tied to PLC control to allow easy adjustment of conveying and operating functions.

The C-more HMI allowed configuration of parameter entries to adjust operator and batch preferences, such as timing and position settings.

The line began with a friction welding station, where tool joints were loaded into a rotating spindle, which was then moved by carriage to contact a section of drill pipe held by a vise.

Parameters such as spindle speed and weld pressure are adjusted by the operator at the station for best results for each pipe type. After welding, the pipe is kicked along conveying equipment to additional stations.

Following welding, pipe is moved to a shear station. Here, an operator loads the pipe, reheats the weld joint using induction heating, and performs various shearing patterns by pushbutton selection. Various timing parameters are user adjustable through the HMI. The shear removes the rough edges around the weld joint. The operator turns the pipe and repeats the shear process until the pipe meets requirements. The pipe is then moved further down the line.

A key station follows where the pipe is austenitized and quenched to strengthen the sections. The austenitizing station is composed of several components and is automated to ensure positioning of components and timing of treatments is optimal and consistent.

The pipe with welded tool joint are first loaded on to a pair of slides that allow precision positioning of the pipe along its length. The slides are operated by motors controlled by Automation Direct 2HP GS2 drives. The drives allow position and speed to be controlled by the PLC, as well as adjustment of acceleration and deceleration patterns. The drives

also worked well at interfacing to a somewhat atypical 380V motor that was provided by the slide manufacturer.

By pressing a start pushbutton on the austenitizing station, and prior entry of key operating parameters for the pipe treatment through the HMI, the station ran through an automated procedure. First clamps closed to hold the pipe on the slides. Next, the pipe moved to a pre-configured position, moving through a stationary induction heater coil. Positioning was controlled by encoder feedback to a CTRIO card in the PLC. This interface allowed the pipe to move quickly towards the set position, then slow as it approached the setpoint, and stop at the exact position desired. The quadrature encoder provided a high resolution count for precision location, and indicated the direction of movement to track forward and reverse positioning over the course of the procedure.

Once at position, the pipe was further clamped and then heated by starting a program in a standalone ramp/soak controller. Near the end of the heat cycle, quench motors are started to ready a quench bath located behind the heater coils. At the completion of heating, holding clamps are released, and the pipe end with tool joint is inserted into the quench bath. Positioning and timing for each quench is configured through HMI parameters to meet the quality needs of each batch. At the conclusion of the quench, each pipe is drawn back by the slides, out of the quench, back past the induction heating, and returns to a clear retract position where it can be then conveyed to the next station.

Following austenitizing, the pipe is moved to a tempering station. Here, multiple pipes are positioned along the conveying line before induction heater coils. Unlike the austenitizing station, here the pipes remain fixed, and the heater coils move forward to a user set distance. Position is again controlled by encoder feedback, with the coils moving to a preset position with an operator procedure start pushbutton. Heating of the weld joint is again accomplished using a standalone ramp/soak controller, although the temperatures are lower and the duration usually shorter than austentizing. Heat levels are adjusted through the controller, by observing pipe temperature with a two color infrared thermometer, and adjusting the power level of the induction heater power unit as appropriate. After the heat cycle completes, the controller signals the PLC, and the heater coils retract. The pipe air cools to strengthen the joint, and the pipe is ready for conveying to the next station.

Finally, the pipe is conveyed to an automated grinding station. At this station, the operator pushes a start button to start the pipe rotating in place, and begin a grinder positioning sequence. Through a series of position and timer settings, the grinder oscillates back and forth along the pipe as it rotates, smoothing any remaining rough spots.

The line is just one of many at the Superior Drillpipe plant dedicated to producing quality drillpipe. By utilizing Automation Direct’s readily available equipment, SDRG Controls was able to quickly tie together the control needs for the production line. With the flexibility and spare capacity the design incorporated, it was possible to make a number of small changes during startup to greatly enhance the quality and ease of use of the system. SDRG Controls continues to support the system and other equipment at the plant, and offers a wide range of design, construction, programming, startup, and documentation services to

its customers.