Free running inserts are designed to make threads or repair worn threads inside tapped holes. They are ideal for providing reliable threading in metals, composites, wood & similar materials. These inserts are usually larger in diameter than tapped holes and are compressed while being inserted, thereby providing maximum surface contact area. Raptor Supplies offers a wide range of free running inserts in Metric, UNC and UNF thread types from Chrislynn and Heli-Coil.
Features
Free running inserts maintain a tight seal, making them suitable for gear housing, drills, printing presses and machinery that produces continuous vibration.
They are produced in standard sizes for Metric, UNC & UNF thread forms.
Chrislynn free running inserts include non-locking helical inserts that can be used to repair tapped holes.
They are available in lengths ranging from 1.688 to 4.5 inches.
Thread reinforcement with helical inserts prevents threaded hole wear (even after repeated use), increasing integrity and extending lifespan.
These flexible inserts are designed such that each coil in the helical insert can adjust to the fastener threads independently. Since the load is evenly distributed, there is more surface contact between the coil and the parent materials, resulting in a strong & reliable seal.
These coil inserts reduce stress and fatigue while maximising thread strength.
Buying Guide
Based On Material
Nickel
These units resist saltwater and caustic chemicals.
Stainless Steel
These units offer excellent resistance to chemicals & saltwater. They meet ASTM A193 temperature & pressure requirements. They are also wear resistant.
Titanium
They have a high strength-to-weight ratio and are resistant to acids & salt water. They are non-magnetic in nature.
Based on Thread Direction
Left Hand Threads
Threads rise from the bottom right to the top left when viewed from the front.
They can be tightened by turning to the left. Once fastened, they resist loosening from counterclockwise motion.
Right Hand Threads
Thread flanks rise from bottom left to top right.
They allow the user to apply greater torque when turning the lead screw clockwise than against it.
Based on Thread Spacing
Coarse Thread Spacing
Coarse threads are spaced widely, allowing them to start easily while requiring the fewest turns to tighten. They are deep and thick, minimising the chances of stripping or jamming, even if nicked / dirty / rusty.
Fine Thread Spacing
These threads are spaced closer together so that they don't loosen when vibrating. As fine threads travel a short distance with each turn, they are ideal for making precise adjustments.
Extra Fine Thread Spacing
They are even more closely spaced than fine threads. These threads travel a very short distance with each turn, allowing for precise & incremental adjustments.
Frequently Asked Questions
How to install helical inserts?
Drill a hole using the suggested drill bit size.
Tap the hole and screw the insert into the installation tool. The prong must be properly engaged in the driving contour of the tool.
Using the installation tool, thread the insert into the hole. Install the insert a quarter to half turn below the hole's surface.
If your insert has a prong, remove it with a punch or break-off tool. This allows the screw to fully enter the insert.
Where are helical inserts without prongs used?
These inserts are frequently used where debris could cause damage because there is no prong to break off and retrieve. They have coils that expand after installation to secure the insert.