How Do Ball Lock Pins Work? Your Comprehensive Technical Guide

Ball Lock Pins are a type of alignment pin used to join and fasten machine components and workpieces with the use of a simple button. These versatile, quick-release fasteners are used in a wide range of industries, including aerospace, automotive, and manufacturing. They are also commonly used in automation and robotics, as well as electronics production. Ball lock pins consist of a pin with a locking mechanism at one end, typically a set of spring-loaded balls. When activated, spring mechanisms draw the balls inside the pin shaft, locking the pin securely in place. When the push button is released, the spring-loaded ball lock is reactivated, retracting the balls and allowing the pin to be easily removed.

Quick-release ball lock pins provide a stable, secure locking function with the receiver plate. This mechanism makes ball lock pins easy to use, and allows for quick parts changeover and replacement, if necessary. Their high shear strength and precision also make them a popular choice for securing components that need to be frequently repositioned or quickly swapped out.

Types of Ball Lock Pins

Ball lock pins are typically categorized by their operating mechanism, with two primary types: single acting and double-acting. Each form offers different functionality for various application needs.

Single-Acting Ball Lock Pins

In single-acting ball lock pins, the locking balls are spring-loaded and automatically engage when the pin is inserted into a hole. This type of ball lock pin is button or handle operated, making them ideal for quick, one-handed operations where only the release mechanism needs to be activated to unlock the pin. Single-acting ball lock pins are frequently used in applications where fast and secure engagement is required, but the pin does not need to be locked manually. They are best suited for environments where ease of use and time efficiency are priorities.

 

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Double-Acting Ball Lock Pins

Double-acting ball lock pins, on the other hand, offer more control by requiring both the insertion and removal of the pin to be manually engaged. In this system, the locking balls are positive locking until released by pushing or pulling the center spindle attached to the pin body handle. Pulling on the handle releases the balls and removes the pin in one motion. Double-acting pins provide greater precision and security, ensuring that the pin won’t lock unless intentionally engaged. This is useful in applications where accidental locking or unlocking could be problematic, such as in safety-critical assemblies or when working with heavy components.

 

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Lifting Pins

Lifting pins are a heavy-duty type of ball lock pin designed to help in the safe and efficient lifting and handling of heavy loads. This type of ball lock pin has a single piece body and is positive locking until released by pushing the button on top of the shaft. Lifting pins allow for quick and secure attachment to a high-tension load, facilitating easy lifting or moving without complex rigging.

 

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Available Handle Styles for Ball Lock Pins

Ball Lock pins have a variety of handle styles, and your choice of handle type will depend on your preference and the requirements of your application. Double-acting ball lock pins can come with a Ring, T-Shaped, or L-Shaped handle.

Ring Handles

Ring handle ball lock pins are designed for ease of use and quick release. The circular ring provides a smaller footprint and requires less space than other handle types, and is the best option if you are not changing your machinery as often and need to save critical space.

 

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T-Shaped Handles

T-shaped handles are the most common form of quick-release pin handle, providing a larger surface area for gripping and great leverage. This design allows for more control when inserting or removing the pin, making it suitable for applications where more force is needed or where precision is critical.

 

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L-Shaped Handles

L-shaped handles are the middle ground between ring handles and T-shaped handles. They offer a compact, angled grip, providing leverage while taking up less space than a T-shaped handle. With an L-shaped handle, the release mechanism is only on one side of the pin, making it ideal for applications that require a solid grip but don’t have enough room to utilize a T-shaped handle.

 

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What Materials are Used in Ball Lock Pins?

Ball lock pins, including heavy-duty lifting pins, are available in a variety of materials and finishes. Ball lock pins are typically made from durable materials designed to withstand high levels of stress, corrosion, and wear, with stainless steel and alloy steel being two of the most common options.

Stainless steel ball lock pins are highly resistant to corrosion, making them ideal for environments where exposure to moisture, chemicals, or other corrosive elements is a concern. Commonly used in industries such as marine, food processing, and medical applications, stainless steel ensures long-lasting performance even in harsh conditions.

Alloy steel ball lock pins offer superior strength and durability, making them suitable for heavy-duty applications that demand high shear strength and impact resistance. While alloy steel is generally more vulnerable to corrosion than stainless steel, it provides enhanced mechanical properties, such as higher tensile strength and hardness.

A manganese phosphate finish is often applied to alloy steel ball lock pins to improve their durability and performance. This finish enhances the steel’s wear resistance and provides a degree of corrosion protection by creating a porous surface that retains lubricants, reducing friction between moving parts. Manganese phosphate also improves the pin’s resistance to galling and seizing, extending the life of the pin and making it easier to use over time.

Additional Technical Information and Pin Selection Recommendations

Your unique application and operation requirements will determine which ball lock pin is best for you. The tables below are designed to assist you when selecting Carr Lane Ball Lock Pins for your application. Strength data indicates the recommended hole diameter and approximate strength for each pin size in our catalog. Data is available for both inch and metric part sizes.

*** Safety factor=2:1. Pins with grip lengths over 8" (special) are not heat treated, in order to maintain straightness. Double shear strength will be reduced approximately 20-50%. Pins in larger diameters than listed here are available as specials (may be made from alternate steels).

MS Conversions

Carr Lane Mfg. offers MS-certified pins as a special at a higher cost. MS-certified pins (Military Standard) are designed to meet stringent military specifications, ensuring high reliability, precision, and durability. These pins are often used in aerospace, defense, and other demanding environments where performance and safety are paramount. Contact us today for your special parts request.

NAS Conversions

Carr Lane Mfg. can also provide NAS-certified pins as a special at a higher cost. NAS-certified pins (National Aerospace Standard) are engineered for use in aerospace applications and adhere to strict guidelines for quality, safety, and performance. These pins are used in aircraft and aerospace assemblies, ensuring they meet the rigorous demands of high-load and high-stress environments. If you’re interested in our NAS-certified options, contact our experts today.

*These are the only standard combinations of Handle Material, Handle Style, Spindle Material, and BLP-BPD type directly convertible from NAS to Carr Lane. Other combinations are available as specials. Browse Carr Lane Ball Lock Pins in the online catalog.

Find the Perfect Ball Lock Pin for Your Application at Carr Lane Mfg.

Ball lock pins offer an ideal solution for applications requiring fast, secure, and reliable fastening. With their quick-release mechanism, high shear strength, and versatility, they are invaluable in industries ranging from aerospace to manufacturing. Whether you need the corrosion resistance of stainless steel, the strength of alloy steel, or specialized options like MS- or NAS-certified pins, ball lock pins provide durability and ease of use in any environment.

Explore Carr Lane Mfg.’s extensive catalog to find the perfect ball lock pin for your specific application. With a wide range of handle styles, materials, and certifications, Carr Lane Mfg. has the right solution to meet your needs and ensure efficient, high-performance results.

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