Experience, Quality and Reliable
If you want to boost the speed and efficiency of your assembly processes, you should look into SEMS, or “pre-asSEMbled” fasteners. These handy devices combine the screw and the washer into a single component, eliminating the need to match the right items up and slip the washer into place by hand. It also simplifies your inventory by giving you one part to track and purchase instead of two. SEMs have been around since the 1930s and come in inch-measure or metric varieties. (Looking for a source…Mr. Metric)

SEMs typically come with some form of lockwasher to prevent slippage once the screw is firmly secured. Two popular choices include internal-tooth and external-tooth lockwashers. Internal-tooth SEMs have teeth have ring the inside diameter of the lockwasher to bite into the substrate and hold the washer in place, while external-tooth SEMs perform the same task with teeth extending from the outside diameter of the washer.

Double SEMs contain two washers instead of just one. In addition to a lockwasher, a double SEM also has a flat washer that sits on top of the locking washer. The lockwasher may have internal or external teeth, but more commonly it comes in the form of a split lockwasher. Split lockwasher see lots of use in automotive and aerospace manufacturing due to their ability to fit into narrow holes. Double SEMS come in brass, steel and stainless steel in sizes ranging from narrow to wide.

Of course, sometimes all these options can get a little confusing. Which SEM is right for your needs? Do you need more than one kind? If you want to make sure you’re ordering the right products, don’t just order blindly — contact us and we’ll be glad to discuss it with you and help you with your purchase.

Experience, Quality and Reliable
In the manufacturing and assembly world, tightening, controlling, or measuring torque fasteners is imperative for production efficiency. An inadequately torqued fastener can vibrate or work loose: conversely, if the tension is too high, the fastener can snap or strip its threads. Faced with these problems, manufacturers are realizing that precise torque control can spell the difference between a safe, reliable, and economical product and complete disaster.

Anybody who has to tighten a threaded fastener and needs to control, monitor, or measure torque needs sophisticated torque tools. If manufacturers want to save money, make their workplace safer, enhance product quality, or reduce their exposure to liability; only specialized high-quality torque tools will get the job done properly.

1. Pick the Right Torque Tool
A wide variety of torque tools are available to control or measure the torque applied to fasteners, from electric screwdrivers to large industrial torque wrenches, torque analyzers, torque sensors, pneumatic screwdrivers and torque multipliers. These tools utilize calibrated torque setting mechanisms that may be factory pre-set or user-definable. When the specified setting is reached, the tool gives a visual, audible, or tactile signal. The anticipated production output, the type of materials being joined, the amount of torque required, and the specified fasteners determine the selection of tools for a given application. Lighter materials such as wood or plastic may require only lightweight tools; likewise, heavy materials such as steel may require stronger or larger tools. If torque data must be gathered during the assembly process or quality process, tools should also have connection ports such as USB, RS-232 and other cabling connections.

2. Establish a Torque Calibration Program
Calibration is fine-tuning the torque control process in a production environment. Torque calibration should be checked periodically to determine whether torque tools are operating at their proper settings. Many tools don’t have a locking device, and users may easily change their torque settings. When this happens, the tool falls out of adjustment.

A regularly scheduled calibration program enables quality control personnel to correct divergence from proper settings, whether it’s because of normal slippage over time or because of adjustments to the tool. Begin by setting a calibration interval initially based on severity of the application and the tool manufacturer’s recommendations. If the applied torque values are out of range, cut the calibration interval in half and re-test the tools.

Read the rest of this page »