SEMS Screws.

What are SEMS Screws?

SEMS screws are fasteners that come pre-assembled with one or more captive washers, such as a spring washer and flat washer (sometimes referred to as a double SEMS screw), to form a single integrated component.

This design eliminates the need for separate washers during assembly, reducing handling time and the risk of losing small parts. Commonly used in manufacturing and assembly lines, SEMS screws and washer assemblies streamline processes by simplifying installation and inventory management.

How SEMS Screws Work

SEMS screws function by integrating captive washers with the screw during production. The captive washers remain fixed in position on the screw shaft, allowing for consistent and efficient fastening without separate washer placement.

This design reduces installation steps and supports applications where dropped components could compromise safety or product integrity. Ideal for high-throughput environments, these screws contribute to lean manufacturing practices by reducing part counts and assembly errors.

Materials SEMS Fasteners Are Made From

Accu's range of stainless steel SEMS screws is manufactured from versatile material options, including high-tensile stainless steel (A2-70), stainless steel (A2-50) and titanium (Grade 1 and 2), ensuring robust performance and excellent corrosion resistance for a wide range of applications. The pre-attached washers, made from stainless steel (A2), grade 1 or grade 2 titanium ensure compatibility with the screw material and maintain overall durability, particularly for demanding environments.

Additionally, AccuLock, our pre-applied thread locking patches, can be incorporated to reduce vibrations and speed up assembly lines, offering enhanced security and simplifying the installation process.

Sizes and Types of Metric SEMS Screws Available

Our metric SEMS machine screws are available in a variety of configurations to suit different applications. They come in metric thread sizes ranging from M3 (3mm) to M6 (6mm) and are offered in lengths from 5mm to 50mm.

Accu's full range of SEMS screws includes a variety of head types, such as cap head, hex head, and pan head, along with multiple drive types, including hex socket, hex head, and Phillips, providing versatile options to suit a wide range of applications.

FAQs

Q: What does SEMS screw stand for in screws?

A: The term SEMS screw originates from the phrase "screw and washer assemblies," which comes from the word pre-asSEMbled. This naming highlights the defining characteristic of SEMS fasteners, their integrated washer configuration that simplifies installation and prevents part loss. The SEMS screw meaning is rooted in this concept of combining components into a single, ready-to-use fastener.

Q: What are the different types of SEMS screws?

A: Types include single washer SEMS screws and double washer SEMS screws, often combining either a single flat washer or a combination of a flat and spring washer.

Q: Why use metric double SEMS screws instead of separate washers and screws?

A: Simply put, SEMS screws rapidly increase installation efficiency, reduce the risk of part loss and improve throughput in production environments. The benefit of time saving outweighs the additional cost per component, similar to how our screws with pre-applied thread lock function.

Q: Are SEMS fasteners reusable?

A: Yes, but washer retention, especially on the spring washer, may decrease with repeated use depending on application and torque levels. As with all screws, check for any visible signs of damage or wear before re-use.

Q: What industries commonly use SEMS fasteners?

A: Industries include electronics, automotive and appliance manufacturing, where speed, efficiency, reliability and component security are essential.

Bespoke SEMS Screws Manufacture.

High precision, bespoke manufacture of SEMS Screws to customer specification. State of the art facilities specialising in both small batch prototyping and large scale manufacture.