Replacing Chart Recorders

Oct 24

A cornerstone of our Heat Treatment Power Pack is adding the ability for continuous data logging to heat treat equipment. Many of the heat treat companies we’ve worked with were previously relying on paper chart recorders for their data collection. While this was a common sollution before the invention of Process Historians, paper chart recorders are outdated and difficult to work with.

An example of a typical paper chart recorder

While paper chart recorders can collect data on furnace operation, and give you a physical record that can be stored indefinitely, they have many shortcomings. They are prone to mechanical issues, and it’s not easy to analyze any of the data stored on the charts. Paper chart recorders limit how you can use the data, and make it very difficult to share the data on any given production run with anyone who might need to see it.

Luckily, modern tools like Ignition make it faster than ever to start collecting useful data. Now, by upgrading with our Heat Treatment Power Pack, you can have easy access to data at any point in time, expanding your capabilities for overall process integration throughout your facility.

Managing Heat Treatment Standards and Regulations with Historical Data

Regulated industries like automotive and aerospace must maintain heat treatment standards and provide proof of work—which requires tracking heat treatment processes. While chart recorders can fulfill these requirements on a basic level, a process historian will provide many more benefits.

First, you can retrieve the data for any batch you’ve run and view all the relevant data on one trend. You can include the actual thermocouple data along with deadband lines for an at-a-glance confirmation that you’ve met the required standards for that run.

Next, you can track the total time the parts spent within the deadband to confirm the batch met the heat treatment requirements for overall soak time.

With a process historian, all of this is completely automated. You’ll no longer need to analyze your paper charts, mark down the time you entered the deadband, track how long you were at temperature, or do any extra work to determine if the part went out of spec during the run.

Improving Operational Efficiency

In addition to thermocouple data, you can historize burner or heater output, gas and electrical usage, valve positions, and data about any atmosphere or vacuum in the furnace.

Using this data, you can determine how well your process controls are tuned are right now. Typically, you will also discover ways to optimize your PID loop tuning to reduce the furnace’s overall utility usage. Many of our heat treatment customers learned that their gas valves were cycling much more often than necessary to maintain temperature—and they were incurring higher gas usage and electrical costs because of the valves cycling constantly. For example, with this information you could adjust the PID tuning parameters to reduce the overall process overshoot when heating up the furnace at the start of a batch.

By tracking the furnace over time, you will find opportunities to implement improvements like a low fire mode between shifts when parts aren’t running. A low fire mode will reduce the amount of time and energy to heat up the furnace at the start of the day.

Then by tracking the parts you’re running, you can identify ways to reduce the overall changeover time for moving from a tempering operation to a normalizing operation, then back to a tempering operation and so on. With this information you can plan out your production schedule to reduce the number of changeovers which will reduce the amount of time and energy required to move between various operations. You’ll meet your customers’ demands for parts while saving time and energy costs.

Automating the Bottom Line

We have also helped our customers increase overall throughput with our Automating the Bottom Line framework. By leveraging production schedules, recipe management, and work orders. We can give operators a drop down selection or a simple work order entry field to select the next batch, auto populate recipe parameters and run a batch at the press of a button. This reduces the amount of information operators need to manually enter and reduces human error. This approach allowed one of our customers to run two additional batches through each of their furnaces per shift. They gained the extra time by eliminating all of the operators’ manual data entry—and the time operator’s had previously spent looking up information for any given batch.

One of our Aerospace customers has a production line with four furnaces, two quench pits and a handful of staging tables. We were able to help optimize their process, including reducing the overall number of steps required to heat treat parts. They saved on direct utility costs with the optimized process by reducing the overall motion of their manipulator since the improved process included an improved plan of which furnaces were used for the required operations relative to their temperatures, cycle times, and locations to quench tanks.

Wrapping Up

Replacing paper chart recorders with automated data collection is a relatively simple concept, but it can have huge positive cascading effects on your overall process.

Integrating your production equipment with your overall business systems for production scheduling, work orders, and recipe management allows you to better plan production on any given shift. Over time, you’ll also be able to find and implement large, cost-saving optimizations.

While helping many customers optimize their heat treatment operations, we have packaged what we’ve learned—along with templatized SCADA graphics and data structures into our Heat Treat Power Pack. This allows us to quickly integrate the heat treatment systems you have, and give you the foundation for future growth into a fully integrated and optimized production system across your entire facility.