Future Proofing Weld Cell Operations

Weld cells are known for their harsh environments, with high temperatures, electromagnetic field disruptions, and weld spatter debris all contributing to the reduced lifespan of standard sensors. However, there are ways to address this issue and minimize downtime, headaches, and costs associated with sensor replacement.

Sensor selection

Choosing the appropriate sensor for the environment may be the answer to ensuring optimal uptime for a weld cell environment. If current practices are consistently failing, here are some things to consider:

    • Is there excessive weld spatter on the sensor?
    • Is the sensor physically damaged?
    • Is there a better mounting solution for the sensor?

For example, sensors or mounts with coatings can help protect against weld spatter accumulation while specialized sensors can withstand environmental conditions, such as high temperatures and electromagnet interferences. To protect from physical damage, a steel-faced sensor may be an ideal solution for increased durability. Identifying the root cause of the current problem is critical in this process, and informed decisions can be made to improve the process for the future.

Sensor protection

In addition to selecting the correct sensor, further steps can be taken to maximize the potential of the weld cell. The sections below cover some common solutions for increasing sensor lifetime, including sensor mounts and bunkers, and entirely removing the sensor from the environment.

Mounting and bunkering

Sensor mounting enables the positioning of the sensor, allowing for alignment correction and the possibility of moving the sensor to a safer position. Some examples of standard mounting options are shown in image 1. Bunkering is generally the better option for a welding environment, with material thickness and robust metal construction protecting the sensor from physical damage as displayed on the right in image 2. The standard mounts on the left are made of either plastic or aluminum. Selecting a mounting or bunkering solution with weld spatter-resistant coating can further protect the sensor and mounting hardware from weld spatter buildup and fully maximize the system’s lifetime.

Image 1
Image 2

Plunger probes

Using a plunger probe, which actuates along a spring, involves entirely removing the sensor from the environment. As a part comes into contact with the probe and pushes it into the spring, an embedded inductive sensor reads when the probe enters its field of vision, allowing for part validation while fully eliminating sensor hazards. This is a great solution in cases where temperatures are too hot for even a coated sensor or the coated sensor is failing due to long-term, high-temperature exposure. This mechanical solution also allows for physical contact but eliminates the physical damage that would occur to a normal sensor over time.

The solutions mentioned above are suggestions to keep in mind when accessing the current weld cell. It is important to identify any noticeable, repeatable failures and take measures to prevent them. Implementing these measures will minimize downtime and extend the lifetime of the sensor.

Leave a comment for a follow-up post if you’d like to learn about networking and connectivity in weld cells.

GIZMOS

Plural of Giz-mo.  A noun.  Defined as a gadget, one whose name the speaker does not know.  Customers call us and ask for this or that “gizmo” all the time!  I think we should consider creating a product category simply called “GIZMOS”.

I like to call these things “Enablers” because these devices are very much helping hands that optimize the function of sensors.  A sensor of any brand and manufacturer performs only as well as it’s mounted, matching the fixture to the demands of the application at hand. But how often does this happen in a price-driven world?  They often end up in below-par mounting that fails with regularity, in both pristine environments as well as in hostile environments.  Some examples:

Here’s one example below. These inductive proximity sensors in plastic brackets, showing an exposed coil on one, with corroded mounts on the sensor caused by being beaten to death during parts loading and heat.

gizmo1      gizmo2

With a few “Gizmos” like an application-specific quick change mount, some care in gapping the sensor and guarding the cable/connector system, it could look much different. Check out the examples below.

gizmo4 gizmo5

Photoelectric sensors can suffer the same fate.  In this case, a plastic bodied photoelectric sensor, originally used to replace a fiber optic thru beam pair also suffered abuse. With a little extra beefy mounting, these photoelectric sensors can be expected to last a long time without failure.

gizmo6 gizmo7

There are literally hundreds of these mounting “ENABLERS”, off-the-shelf, cost-effective application specific mounts, guards, actuators and entire systems to help protect your sensor investment.  All categories of products have these “enabling” accessories for Magnetic Field (air cylinder), Inductive Proximity, Capacitive, Ultrasonic, Connectivity, Linear Transducer and Photoelectric product categories.