Welding Digest

The Building Blocks to an Automated Robotic Welding System for Longer, Leaner Operations Here’s how an automated welding system provider works with its customers to build these systems from the group up, thus mitigating risks and smoothening the transition to fully automated.

In the 1980s, lean manufacturing took off to minimize the excessive waste being generated on the factory floor. Today, there’s another goal: combating the skilled labor shortage. Pemamek LLC, West Chester, Ohio, a worldwide provider of automated welding and production solutions, partners with its customers from the outset to determine which components of its modular welding systems will work best for their operations.

Leaning into the Process

When a company decides to invest in an automated system, it should examine the overall operation in terms of excess and, if possible, measure it against the five principles of lean manufacturing. It also makes sense to include any potential partners from the outset.

First, the customer’s entire operation is dismantled on paper and broken down into pieces for close examination. Equipment, the number of personnel needed to run it, how efficiently things (and people) are running, production rates, overall part quality, and waste generation are evaluated. Time and cost analyses are performed. Pemamek speaks with the people intimately involved with the welding process and in overall production to understand which modules of an automated system will work best to achieve the company’s goals. Elements of the Kaizen™ philosophy, includ-ing customer expectations, data collection and consideration, involving and empowering the team, and letting it all flow into an actionable plan to optimize the welding process, can be implemented here.

Simulating the Operation

At this stage, all facets of the process need to be considered as the shop floor is put back together virtually, including the steps that appear excessive. For example, all welding operations are simulated using the parts’ minimum and maximum dimensions to determine the size of the automated welding station. Transferring the current process to a robotic welding process as well as developing new approaches needs to be done collaboratively with welding engineers on both sides. Finally, once the welding cell is installed, all designs and operations need to be evaluated and, as necessary, modified to ensure the desired welding procedure specifications (WPSs) are followed exactly.

The WPS’s Role in System Design

All welding jobs begin with the WPS, which is defined by the customer but can be fit into different welding systems. Important welding considerations, such as heat inputs and weld strength re-quirements, are spelled out. So are customer quality needs, which can depend upon the weight of the structure, the material being welded, and end use. Base material selection is of particular im-portance because weld joints must be stronger than the base material itself. The WPS is the base upon which the entire welding system is built. For companies with multiple WPS jobs, a modular approach to designing an automated welding system is the way to go for optimum flexibility and simplicity. Each cell can be tailored for each job. Together, the cells make up an entire system.

Software Controls the Building Blocks

A flexible manufacturing system (FMS) enables unmanned flexible heavy steel manufacturing. The PEMA FMS uses the proprietary routing software Line Control to identify the workpiece by radio frequency identification (RFID) or QR code and direct it via conveyor to the appropriate process cell. The system tracks all work phases, progress, status and queue position. This type of system is truly flexible in that all welding stations are capable of working independently of one another, in-creasing manufacturing capacity and throughput exponentially. Further, it’s scalable, enabling shops to start small and then build onto the existing system to meet demand.

These days, most welding jobs begin with a 3D welding part drawing. When a 3D model is not provided, automation plays an even bigger role in keeping the operation running as leanly as possible. Getting a firm handle on the number and type of consumables necessary for a particular welding process plays an integral role in creating a lean manufacturing environment.

Semi-narrow groove welding uses fewer consumables over the length of a welding operation and encourages flux reuse. By starting with a workpiece milled to the ideal welding groove geometry, the volume of the weld joint is minimized while the joint itself is geometrically correct with clean groove edges.

After Welding, We Recycle

Welding flux is a constant in any welding operation, but it can be reused and recycled as long as moisture doesn’t seep in. This is done by vacuuming unused flux, classifying it with a vacuum classi-fication system, and redepositing the reusable flux into a heated vessel that removes moisture to a predetermined level. It’s then mixed with the incoming fresh flux. The entire process leads to in-credible time and cost savings in terms of wire extrusion and electricity. It also saves on material costs and shipping times.

Building a Leaner Operation from the Ground Up

Robotic production cells are the building blocks used to build complete automated robotic weld-ing systems. By partnering with your supplier, you begin with a reliable pre-analysis completed by the people who know the system best and done in tandem with the people who know your opera-tion the best. This approach sets up your shop to run leaner.

This article was written by Michael Bell (director of North American sales, Pemamek LLC) for the American Welding Society.