First, let’s review what pre-assembled screws aka SEMS are. The SEMS name derives from pre-assembled highlighting the letters SEM. Simply put they are bolts that come pre-installed with a washer. The washer is fastened to the bolt before threads are machined onto the bolt. This permanent feature keeps the washer from falling off the bolt. One can imagine the multitude of reasons using SEMS can benefit machine installation and design, some of those reasons are listed below.
1 – Fast Installation
Since SEMS are complete with a washer, this makes the installation of your components faster and easier. It removes the added step of finding the right washer and installing it onto the screw. Especially for small spaces and designs, SEMS can come in handy. This can increase productivity and reduce build time.
2 – No Lost Washers
Losing a washer between cracks of a machine build can be a headache not only with time but with inventory and cost. With SEMS, the washer will be less likely to be lost during machine build. The machine builder can assemble with confidence that the washer is secure.
3 – Fewer Part numbers on Your Bill of Materials
This benefit can often time be overlooked as it is simply one line. However, the use of screws and bolts in a machine is extensive and having to spec a washer for each one can be time-consuming so having fewer part numbers on your bill of materials can have a big impact on machine design.
4 – Reduced Inventory
Inventory space can be a luxury for some and it’s surprising how much space a lot of washers can take up, not having to account for two separate part numbers are a benefit of pre-assembled screws in regards to inventory.
5 – Great for Hard-to-Reach Areas
SEMS can also benefit the repair or service and disassembly processes especially in certain areas of the machine that are difficult to access. No more worrying about loose washers during disassembly. It’s both safer and less time-consuming.
6 – Versatile Use
Pre-assembled screws can be used in a variety of applications from battery pack assembly to laboratory automation machines. Their versatility is vast.
SEMS are also very cost-effective and can help extend machine life. MISUMI carries a variety of SEMS or captive washers screws for any industry and application. For example, you can select various head/drive/washer combinations including low head, Phillips drive, or even with double washers. You can review the selectionhere.
Feel free to share your experience and the benefits you’ve found using SEMS below.