Sems Screws

Captive Screws are a highly diverse group of fasteners that are distinguished by their capacity to remain in an assembly even after it has been disassembled. As a consequence, fastener loss and any interruption or damage brought on by a loose component may be prevented.

What are SEMS Screws, and Captive Screws?

SEMS screws, also known as captive screws, are machine screws that come pre-equipped with lock washers to speed up assembly. They merge two unique elements into a single, inexpensive fastener that is already assembled. Captive fasteners include washers beneath the head, which facilitate quick installation, durability, and simple application adaptability. By eliminating the possibility of the washer going missing when utilizing SEMS machine screws, you can increase the lifespan of your product and guarantee reliable performance.RS is the best supplier for SEM screws. Steel and stainless steel SEMS screws in a range of sizes and head designs, including hex head seem screws, hex washers, pan heads, and m3 to m10 SEMS screws are among the many items we have in stock. Additionally, we provide a complete range of metric SEMS screws.

When and Why do Industry Applications Need Captive and SEM Screws?

Industrial equipment often uses captive fasteners since missing or loose screws may harm the machine seriously, especially if they fall into a delicate component.Other uses for captive fasteners include the following:Computer cases enable cover panels to be safely removed in order to access the interior without running the danger of the screws piercing the computer's internal components.Race cars - assist in preventing pieces from coming free and dropping onto the track, since track debris may cause serious accidents if it becomes stuck in tyres.Military Applications - These fasteners may be necessary for the construction of military equipment where panels must be swiftly and effectively removed and replaced without the possibility of contamination by extraneous objects.Captive panel screws for aircraft may help to guarantee that vital parts of the aircraft are not misplaced or damaged when undergoing maintenance or repairs.In order to comply with the EU Machine Safety Directive 2006/42/EC, captive fasteners are needed by law on various items of equipment and safety devices, including safety guards.

Captive Screw and Washer Installation

The Captive Screw and a Captive Washer are positioned on opposing sides of a loose panel or target housing during installation. Captive Washers can only be placed with their internal teeth pointing away from the screw's head in one direction.As a result, the washer is kept from reversing over the screw's threads and is kept in place inside the assembly or panel. A considerable amount of effort is required to drive the captive screw through the internal diameter of the captive washer during this installation procedure since the fasteners are designed to provide a durable grip.Simply said, the larger size of the components involved makes this especially true the larger the screw thread diameter.