Helicoil inserts are a type of fastener used to repair or reinforce threads in metal parts․ They are known by different names, such as V-coil and Elicel․ These inserts conform to DIN 8140 and provide a durable solution for damaged threads․
What are Helicoil Inserts?
Helicoil inserts, also known as wire thread inserts, are precision-engineered fasteners made from high-quality materials like stainless steel․ They are designed to create strong and durable threads in various materials․ These inserts are used to repair stripped, damaged, or weak threads, providing a more robust and reliable connection point․ Helicoils can be used in new applications to improve thread strength and wear resistance․ They are available in free-running and screw-locking types, offering versatility for different needs․ They comply with standards like DIN 8140․
Helicoil Product Range
The Helicoil product line includes free-running and screw-locking inserts․ These are made from various materials, including Nimonic 90, Nitronic 60, titanium alloys, Inconel X-750, and phosphorus bronze, catering to diverse needs․
Types of Helicoil Inserts
Helicoil inserts are available in various types to suit different applications․ These include free-running inserts, which provide standard thread engagement, and screw-locking inserts, which offer increased resistance to loosening․ Additionally, there are tanged and tangless inserts, each with their installation methods․ The material choices range from standard stainless steel to high-performance alloys like Nimonic 90 and Inconel X-750, ensuring there is an appropriate insert for almost any environment and requirement, including those found in aerospace and other demanding industries․ These options allow engineers to select the best insert for their particular needs․
Helicoil Size Charts
Helicoil size charts provide essential information for selecting the correct insert․ These charts include tap and drill sizes for different thread types, helping users choose the right components․
Tap and Drill Sizes for Helicoil Threads
Selecting the correct tap and drill sizes is critical for successful helicoil installation․ For instance, a 2-56 thread requires a 3/32 drill size, while a 1/4-20 thread needs a 17/64 drill․ These sizes, often listed in charts, ensure proper fit and function․ The tapped hole should adhere to ASME B1․1 standards, but with an increased diameter to accommodate the insert․ Proper drilling and tapping are crucial for thread integrity․
ASME B18․29․1 Standard
The ASME B18․29․1 standard specifically addresses helical coil screw thread inserts, both free-running and screw-locking, in inch series․ This standard defines the dimensions and tolerances for these inserts․ The tapped hole for the helicoil must be made according to ASME B1․1, with the exception of the diameter, which is larger to accommodate the insert․ This ensures that the inserts function effectively within specified parameters, maintaining consistency in thread repair and reinforcement․ It’s essential to consult this standard for proper application․
Helicoil Installation Process
The installation process involves drilling a hole, tapping it with a special STI tap, and then installing the insert using a dedicated tool․ This procedure is crucial for proper thread repair and reinforcement․
Drilling and Tapping
The first step in the Helicoil installation process is drilling the hole to the correct size․ This requires using a standard drill bit appropriate for the material being worked on․ Following drilling, the hole must be tapped using a specific STI tap designed for Helicoil inserts․ This ensures that the tapped hole is properly sized to accept the insert․ The tap size will differ from standard threads as it is larger to accommodate the insert․
Insert Installation
After drilling and tapping, the next step is to install the Helicoil insert․ This is done using a specialized installation tool․ The tool engages the tang of the insert and screws it into the tapped hole․ Once the insert is fully seated, the installation tool is removed․ The tang is then broken off at the notch, creating a fully functional and reinforced thread․ The process is straightforward but requires careful execution․
Helicoil Thread Specifications
Helicoil inserts are available in both inch and metric thread sizes․ These specifications are crucial for selecting the correct insert for a given application․ Dimensions are determined by standards․
Inch Thread Sizes
Helicoil inserts are manufactured to accommodate a wide array of inch-based thread sizes․ These range from very small sizes, such as 2-56, up to larger diameters like 1-1/2 inch․ Common sizes include 1/4-20, 5/16-18, and 3/8-16․ The correct selection depends on matching the insert thread to the fastener being used․ Specific tap and drill sizes are crucial to ensure proper installation per ASME B18․29․1 standard․
Metric Thread Sizes
Helicoil inserts are also available in a comprehensive selection of metric thread sizes, ranging from M2 to M39․ These metric sizes include both coarse and fine thread options, providing flexibility for various applications․ Accurate tap and drill dimensions are essential to achieve the correct fit when using these inserts․ The selection of the correct metric size is crucial for proper thread engagement, therefore, it is important to follow manufacturer’s specifications․
Helicoil Materials
Helicoil inserts are made from various materials, including specialty alloys like Nimonic 90, Nitronic 60, and Titanium․ Inconel X-750 and Phosphorus Bronze are also used for specific applications, ensuring suitability for diverse environments․
Specialty Alloys
Helicoil inserts are not limited to standard materials; they are also manufactured using a range of specialty alloys․ These include high-performance options like Nimonic 90, known for its high-temperature strength, and Nitronic 60, which offers excellent corrosion resistance․ Additionally, inserts are available in Titanium alloys, which provide a high strength-to-weight ratio, Inconel X-750, known for its resistance to extreme conditions, and even Phosphorus Bronze for specific applications requiring good conductivity․ These materials expand the application range of helicoil inserts, making them suitable for demanding environments․
Helicoil Applications
Helicoil inserts are widely used for both thread repair and reinforcement․ They restore damaged threads to their original size and also strengthen threads in softer materials, preventing future wear․
Thread Repair
Helicoil inserts offer an effective solution for restoring stripped, worn, or damaged threads․ These inserts allow for the reuse of components that would otherwise be scrapped, saving time and resources․ They quickly and permanently return threads to their original size and condition, ensuring a secure and reliable fastening․ Whether dealing with cast aluminum or other materials, helicoils can adapt to various thread types, even accommodating slightly larger screw sizes․ This makes them a versatile choice for a range of repair applications․
Thread Reinforcement
Helicoil inserts are not only for repair, but also excel at reinforcing threads in new or existing designs․ By installing these inserts, tapped holes are strengthened, and thread life is dramatically increased․ This added strength is particularly beneficial in materials like aluminum, where threads can be easily stripped․ The use of helicoils provides a more robust and durable thread, allowing for repeated assembly and disassembly without compromising the integrity of the connection․ This reinforcement ensures long-lasting performance and reliability․
Helicoil Tooling
Helicoil offers a comprehensive line of tooling to facilitate the installation process․ This includes manual tools designed for efficient and precise installation of inserts into prepared tapped holes․
Manual Tools
Helicoil provides a range of manual tools designed for the installation of their wire thread inserts․ These tools are essential for applications where automated tooling is not feasible or necessary․ The manual tools include items for inserting the helicoil into the tapped hole and for breaking off the tang once the insert is properly installed․ They are designed for ease of use and provide the required control for accurate installation․
Helicoil Length and Dimensions
Understanding the length and dimensions of Helicoil inserts is crucial for proper installation․ These dimensions are based on the thread size and the required insertion depth for effective thread repair or reinforcement․
Insert Length Calculation
Calculating the correct Helicoil insert length is essential for optimal performance․ The length is typically determined by multiplying the nominal bolt diameter by a factor, often 1D, 1․5D, 2D, 2․5D, or 3D, where D represents the diameter․ This calculation ensures the insert provides adequate thread engagement․ For example, an insert length equal to the nominal bolt diameter and 1․5 times the bolt diameter is used in the case of aluminum alloys, while for a screw-in thread length of 1․5 d, the dimension H is calculated as H is equal to the insert nominal length minus the pitch․
Tapped Hole Dimensions
The tapped hole dimensions for Helicoil inserts are critical for proper installation and performance․ These dimensions are typically larger than standard threads to accommodate the insert’s wire coil․ The tapped hole must adhere to specific pitch diameter limits․ According to the ASME B1․1 standard, the tapped hole’s diameter is larger to accommodate the insert․ Dimensions are available for both plug and bottoming taps․ Metric tapped hole dimensions are available from M2 to M39, following ISO standards, and they are needed to ensure the correct fit of the insert․
Helicoil Standards and Specifications
Helicoil inserts adhere to various standards, including ASME and DIN․ These standards ensure quality and compatibility․ The ASME B18․29․1 standard is particularly relevant for helical coil screw thread inserts․
ASME and DIN Standards
Helicoil inserts comply with both ASME and DIN standards, ensuring they meet rigorous quality and dimensional requirements․ Specifically, ASME B18․29․1 governs helical coil screw thread inserts, detailing dimensional specifications for free-running and screw-locking types․ These standards ensure interchangeability and reliable performance across various applications․ The DIN 8140 standard is also a key reference, further solidifying the international acceptance of helicoil inserts and their manufacturing parameters․ These standards guarantee the inserts perform predictably when used in different locations and applications․