{"id":14604,"date":"2025-03-27T08:44:00","date_gmt":"2025-03-27T13:44:00","guid":{"rendered":"https:\/\/blog.misumiusa.com\/?p=14604"},"modified":"2025-07-15T09:28:54","modified_gmt":"2025-07-15T14:28:54","slug":"specialty-fasteners-mechanical-engineer","status":"publish","type":"post","link":"https:\/\/us.misumi-ec.com\/blog\/specialty-fasteners-mechanical-engineer\/","title":{"rendered":"7 Specialty Fasteners Every Mechanical Engineer Should Know About (And Where to Find Them)"},"content":{"rendered":"\n

With so many options for fasteners, it\u2019s easy to stick with what you know. When we talk to engineering teams across industries, from warehouse automation<\/a> to semiconductors<\/a>, they\u2018re surprised when they find out how many different fasteners MISUMI offers that are designed (or are configurable) to fit their needs.<\/p>\n\n\n\n

Though we have a long list of specialty fasteners<\/a>, there are a handful that have grown in popularity across industrial automation sectors. These fasteners are popular for a variety of reasons, from uniqueness to time and cost savings.<\/p>\n\n\n\n

Here are six specialty fasteners to put on your radar (and you can find them all at MISUMI!).<\/p>\n\n\n\n

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1. Ultra Low Head Screws<\/h2>\n\n\n\n

Standard fasteners that are used in factory automation are often mated to a counterbored hole to reduce the profile of the head sticking out due to interference, worker safety from being snagged on the protruding head, and provide an overall more compact design.<\/p>\n\n\n\n

Ultra-low head screws<\/a> are space-saving fasteners<\/a> that save machining time by not needing a counterbored hole while still providing all the above benefits. Additionally, without a counterbore, these screws are aesthetically pleasing.<\/p>\n\n\n\n

Like other machine screws, these screws are intended to fit into mating internal thread profiles. To accommodate the flat head profile, the hexagonal head drive slot is recessed into the screw.<\/p>\n\n\n\n

These screws can fit into applications where there is minimal clearance from other assembly components, where space is limited and access to the joint is restricted. <\/p>\n\n\n\n

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MISUMI Ultra-Low Head Cap Screws<\/a><\/figcaption><\/figure><\/div>\n\n\n\n

2. SEMS Screws with Pre-Assembled Washers<\/h2>\n\n\n\n

Also known as \u201cwasher integrated screws, \u201cpre-assembled screws,\u201d or \u201ccaptive washer screws,\u201d there are several benefits of using SEMS screws<\/a>.<\/p>\n\n\n\n

SEMS come pre-installed with a washer, which is fastened to the bolt before threads<\/a> are machined onto the bolt. This permanent feature keeps the washer from falling off the bolt.  <\/p>\n\n\n\n

While many design engineers don\u2019t consider the amount of time it takes for a worker to place a spring washer and flat washer<\/a> onto a screw, a process engineer looks at this with great interest when there are hundreds or thousands of fasteners per machine.<\/p>\n\n\n\n

As a result, SEMS screws are great when going from prototype to mass production because they save assembly time and money. Additionally, with SEMS fasteners, there are fewer part numbers on your BOM to manage, reducing procurement costs, inventory space, and assembly steps.<\/p>\n\n\n\n

They\u2019re also versatile; they are used in a variety of applications from battery pack assembly<\/a> to laboratory automation machines.<\/p>\n\n\n\n

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MISUMI Head Cap Screw with Standard Washer Set<\/a><\/figcaption><\/figure><\/div>\n\n\n\n

3. Fasteners with Threadlocker<\/h2>\n\n\n\n

Threadlocking adhesive offers vibration resistance and corrosion protection.<\/p>\n\n\n\n

Similar to the benefits of SEMS screws, instead of having to pay someone to apply adhesive to the fastener before installing, these ship with the threadlock already on the fastener threads, saving on assembly time and assembly costs.<\/p>\n\n\n\n

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MISUMI Socket Head Cap Screws with Threadlocker Adhesive<\/a><\/figcaption><\/figure><\/div>\n\n\n\n

4. Extra-Low Head Captive Screws<\/h2>\n\n\n\n

Similar to the benefits of extra-low head screws, the captive feature<\/a> ensures that the screw remains attached to the component, even when loosened, which prevents loss.<\/p>\n\n\n\n

The compact head makes them ideal for tight spaces. They feature a narrow, unthreaded shank just below the head and a relief-cut thread with a larger diameter at the tip.<\/p>\n\n\n\n

When loosened from a structure or application, the relief-cut thread design keeps the screw secured to the panel, preventing it from falling off.<\/p>\n\n\n\n

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MISUMI Captive Panel Screws<\/a><\/figcaption><\/figure><\/div>\n\n\n\n

5. Shoulder Screws<\/h2>\n\n\n\n

Shoulder screws<\/a> have a distinct unthreaded shoulder section between the head and thread, which allows them to function as shafts, axles, pivot points, and guides for rotating or sliding components in various industries, including aerospace, manufacturing, and consumer products.<\/p>\n\n\n\n

Also known as \u201cshoulder bolts\u201d or \u201cstripper bolts,\u201d shoulder screws aren\u2019t necessarily considered a specialty fastener. However, MISUMI offers different shoulder tolerances of h7, e9, or g6, and you can configure the shoulder length as well.<\/p>\n\n\n\n

They are often used in applications such as punch and die mechanisms, plastic injection molds, and precision assemblies where accurate alignment and smooth movement are required.<\/p>\n\n\n\n

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MISUMI Shoulder Screws: Tolerance h7<\/a> | Tolerance e9<\/a> | Tolerance g6<\/a><\/figcaption><\/figure><\/div>\n\n\n\n

6. Helical Inserts\/Threaded Inserts<\/h2>\n\n\n\n

Helical (threaded) inserts<\/a> reinforce threads, reducing wear and making them more resistant to stripping, especially in softer materials like aluminum or plastic. They are great at lightweight construction.<\/p>\n\n\n\n

Most threads tend to put the load on quite a small area of the thread, and some materials are prone to galling threads. But helical inserts have a bit of flex, which helps with load distribution.<\/p>\n\n\n\n

As a result, there is an increase in wear resistance, additional thread friction, and durability of the screw joint than without.<\/p>\n\n\n\n

Depending on the material, some inserts also provide corrosion resistance.<\/p>\n\n\n\n

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MISUMI Threaded\/Helical Inserts, Stainless Steel, Coarse<\/a><\/figcaption><\/figure><\/div>\n\n\n\n

7. Non-Metallic Screws<\/h2>\n\n\n\n

There are a ton of applications where nonmetallic fasteners<\/a> are ideal or even required. Whether it be aerospace to save on weight or prevent corrosion in harsh environments, semiconductors for electrical insulation purposes, or medical devices to ensure sterility, corrosion resistance, and biocompatibility, the list of benefits is long.<\/p>\n\n\n\n

Within the non-metallic fastener<\/a> category, PEEK screws<\/a> are ideal. They are lightweight, high-strength, and resistant to extreme temperatures. PEEK offers a higher strength than other polymer screw materials such as PTFE, PFA, PVDF, and Vespel.<\/p>\n\n\n\n

While natural PEEK is very strong, fiber-reinforced PEEK, like PEEK Extreme and glass-filled PEEK fasteners, can be nearly as strong as some steel fasteners. In addition to PEEK, Misumi also offers other nonmetallic fastener material options such as RENY, PPS, and PVDF, to name a few.<\/p>\n\n\n\n

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MISUMI Plastic Screws with Hex Socket Head Cap<\/a><\/figcaption><\/figure><\/div>\n\n\n\n

Clean and Pack Options<\/h2>\n\n\n\n

Clean and pack<\/a> is a cleaned parts option available through MISUMI. It\u2019s a cost-effective and faster alternative to getting parts cleaned by a third party.<\/p>\n\n\n\n

Many of the fasteners highlighted (plus many more<\/a>) are available for purchase pre-cleaned.<\/p>\n\n\n\n

The three clean and pack options<\/a> include:<\/p>\n\n\n\n

\"MISUMI<\/figure><\/div>\n\n\n\n

Why MISUMI for Specialty Fasteners?<\/h2>\n\n\n\n

When you choose MISUMI for fasteners, you get:<\/p>\n\n\n\n