Eliminate the Problem of Missing Screws with Batch Count Functionality

Complex fastening regimes with multiple screws and high-speed production can lead to miss screws and compromised quality. Get it right the first time around with batch count and line control functionality.

Problem: On fast moving assembly lines, operators can miss screws.
Solution: Screw counting capability with operator feedback signal.

Problem: Operator needs to mark every screw in order to check each one is fastened.
Solution: Screw counting function and line control capability. When all the screws are in place, the torque screwdriver sends a signal to the line and next batch arrives.

Screw Counter
A screw counter helps manufacturers detect and eliminate costly screw-fastening errors during the assembly process. Using a screw counter is like putting the eyes and ears of a quality control manager where they are needed most – right on the assembly area. Screw counters verify that all fasteners have been installed and were seated to the tools preset torque setting. These units take the control of the assembly process out of the operator’s hands.

Designed to detect cross-threading, omissions, unfinished rundowns and cycles incomplete, a screw counter ensures the assembly process is done correctly the first time. The device typically operates jointly with assembly tool like an electric or pneumatic screwdriver or some torque control systems have it built-in. The screw counter features the ability to ‘learn’ the characteristics of not only the assembly tool but also that of the application that it is being used on. This allows the screw counter to distinguish between a fastener that was properly seated and one that was either stripped or cross-threaded.

Lapses in preventing fastening errors can affect the bottom line. Fastening errors can be realized as catastrophic or latent failures. Catastrophic failures are easier to detect and resolve. With this type of failure the part is “dead” and will not function. It may be costly to repair but is easy to manage. With latent failures the problem is much worse as the failure may not be detected in testing but is a “time bomb” waiting to happen. Since this product will get into the field and cause intermittent problems or failure in the field, it can be a much more costly problem.

The intent of the screw counting process is to ensure that all screws are accounted for during the assembly process. The later an error is detected on the assembly line, the more it costs in rework time and expenses. If a fastening error is committed and detected during the assembly process, the operator can it fix by properly completing the process or prevent the faulty product from being moved down the line.

If the error from one station is passed on to another station, the additional cost becomes higher. Either the next operator will have to dismantle the product to re-tighten the bolt or go back to a previous station to get components to correct the error. Or there might be a specially designated rework area in the production area. All increase cost and cause production delays.

When searching for a screw counting system there are several key features to search for, like a unit that gives the operator an audible and visual indication that the assembly has been completed or if it has been rejected. The screw counter displays the type fastening error that occurred as well

The screw counter should feature the ability to store multiple fastener settings for applications that use a variety of fasteners. A flexible screw counter can be integrated with a PLC system, to activate other functions for line control. Look for screw counter that offers password protection to prevent incidental or operator tampering of settings. Also a screw counter that features a compact design and mounting brackets allows the unit to easily be integrated into the workspace without disrupting the production flow.

Mountz offers the Scout screw counter, which operates jointly with Mountz electric screwdrivers and STC30 power supply. Mountz also offers the HD-Series Hybrid Torque Control system that features built-in screw counter.

A screw counter improves production yields, manufacturing costs, product quality, product reliability, reputation and profitability by ensuring that every assembly has been subjected to a quality control check process right on the assembly line.