Mastering Roller Chain Link Removal: A Step-by-Step Guide
Removing a chain link is an essential step for almost any chain maintenance, repair, or installation procedure. This guide provides a comprehensive breakdown of the process for removing a link from an industrial precision roller chain.
While the specific tools and techniques may vary depending on the chain type and application, the core principles outlined here are universally applicable. Although it is impossible to cover the specifics of link removal for all varieties of industrial chains in one guide, the concepts presented herein can be readily applied to other scenarios involving engineered class chains or chain conveyor systems.
By following clear, step-by-step instructions and considering the specific chain type and situation, you will improve your knowledge in the area of chain link removal and gain confidence to perform it efficiently in the field.
Step 1: Prepare Personal Protective Equipment (PPE)
The act of removing a link, especially using tools like punches or applying pressure, can cause metal fragments to chip off and strike at high speed. Safety glasses are crucial to shield your eyes from these potential projectiles and prevent serious injuries.
While eye protection is critical, it is also important to wear appropriate gloves with a good grip to handle tools and the chain securely. Sturdy footwear protects your feet from dropped tools or chain components.
Remember, PPE is not optional. Wearing the proper equipment safeguards your well-being throughout the chain link removal process.
Back to the Top
Step 2: Identify & Locate the Link
Identifying and locating a link to be removed directly depends upon the specific purpose of removing the link and falls within one of the following scenarios.
Identifying a Specific Link to Be Removed (Master Link or Damaged Link)
Identifying a master link is the most straightforward scenario of the purpose of its removal or location on the chain loop. It differs from other links, and it will be immediately noticeable when examining the chain.
Similarly,
identifying a link that's broken, bent or deformed is an easy task. A visual inspection along the chain will allow you to identify it based on those obvious signs of damage you're looking for.
Back to the Top
Choosing a Link for Chain Removal from the Drive
When you need to remove a chain from the drive it is installed on and it
doesn’t have a master link, the selection of the link for removal will be based on its accessibility for the removal procedure. Because all inks are identical and you don’t search for a specific link, it doesn’t matter which link is removed. Moreover, you can move the selected segment of the chain by rotating the sprockets for optimal access and ease of disassembly.
Back to the Top
Determining the Number of Links to Adjust the Length of the Chain
The last two cases of link identification are
adjusting the appropriate length for a new chain installation and shortening a stretched chain due to slack. Both of them require a more precise approach than the previous two scenarios.
When
installing a new chain, appropriate calculations are necessary to determine the length of the chain based on the specifications of the drive. When you gather the drive specifications such as the number of teeth on both sprockets, their diameter and the distance between their centers you will be able to determine the number of links you will require in the chain loop. From there you will know how many links you need to remove from the standard 10 ft roll of chain and will identify the specific location of the link you need to disconnect.
When you are
shortening a stretched chain, the chain stretch measurement and the desired amount of slack reduction will determine the number of links to be removed.
Back to the Top
Step 3: Stabilize the Link
This step involves two scenarios, depending on the link type and whether the chain is on the drive or has been removed.
Secure the Chain on a Workbench
This scenario applies for:
- Pin grinding on a riveted chain removed from the drive (Steps 4 and 5).
- Driving the pins out with a hammer and punch from all types of chain links with press-fit side plates (Step 5).
Secure the chain section in a vise, ensuring the link you want to remove is easily accessible. Clamp the vise jaws firmly on the chain without damaging it. You can use protective jaws or rags to avoid marring the chain surface.
Alternatively, you may use a
fork and anvil block. It is another bench tool commonly used for uncoupling precision steel roller chains. It consists of two pieces, a fork and an anvil block, commercially available for different chain sizes.
Both of these devices are typically used for chain disassembly when the chain has already been removed from the drive or conveyor. Using them on a chain drive may present some difficulties unless you are able to mount them on a tripod and place it under the chain strand.
Back to the Top
Stabilize the Chain on a Drive
This scenario applies for:
- Pin grinding on a riveted chain that is connected to a drive (Step 4).
- Limited applicability: This method might not work for all sprocket designs.
When the chain can't be removed from the drive without removing a link, you will need to restrict movement and create substantial support for the link removal. Sprockets can also be used to create a stable working area for chain disconnection. You may use C-Clamps for that purpose to secure the chain on a sprocket. This scenario requires extra caution and might not be suitable for all sprocket designs. If the sprocket has limited flat areas or a complex spoke pattern that prevents safe clamping, using a vise (as described earlier) is the safer option.
- Identify a clamping location. Look closely at the sprocket. You need a solid, substantial area on the outer portion of the sprocket body away from the teeth. For example, this could be a flat section between the sprocket's center hub and the teeth. Avoid clamping on curved surfaces.
- Position the chain. With the chain still attached to the sprocket, rotate it so the rivet you want to remove is next to the clamping location you identified on the sprocket body.
- Protect the sprocket (optional). If you're concerned about scratching the sprocket surface, place a rag between the C-clamp jaw and the chosen clamping area.
- Clamp the chain and sprocket. Prepare a large C-clamp with the opening wide enough to fit the chain and a section of the sprocket body. Position the C-clamp with its jaws facing each other. Tighten the C-clamp screw gradually until the chain section is secured firmly without slipping. Avoid over-tightening, which could damage the chain or sprocket.
Back to the Top
Step 4: Remove Pin Fastening
How to Remove a Master Link
Spring Clip Master Link
To remove a spring clip master link, you may try using regular pliers or source specialty pliers that typically have staggered jaws. Place one tip of the plier jaw against the edge of the open end of the spring clip and the other tip on the opposite side of the nearest pin. Press the plier handles together to push the spring clip in the direction opposite to its installation. Once it unclamps from the link pin, it will easily come off, and you may proceed to Step 5 to disconnect the side plate.
Cottered Pin Master Link
For this type of master link, you may use specialty cotter pin removal pliers, but regular thin-nose pliers would typically suffice. More importantly, wear safety glasses to protect your eyes from flying debris when straightening the cotter pin ends.
The steps are as follows:
- Use pliers to straighten the bent ends of the cotter pin.
- Once the ends are straight, carefully pull the cotter pin out of the hole in the link pin.
- Proceed to Step 5 to remove the side plate.
Back to the Top
How to Remove a Cottered Chain Pin Link
While the process for removing a cotter from a cottered chain pin link is similar to removing it from a master link, here are some more details. There are three main types of roller chain cotter pins:
- Staggered Leg Straight Split Cotter Pin
- Shepherd's Crook or J-Hook Cotter Pins
- Z Style Cotter Pin (Solid Long Cotter)
Back to the Top
Staggered Leg Split Cotter Pin Removal
The Staggered Leg Split Cotter Pin is the most common and widely used. When disassembled from the chain link, it is straight, with the leg split into two, and the ends have staggered lengths - one is slightly longer than the other.
The methods of securing the side plate on the link pins with a split cotter divide into two subtypes:
- Using a long single cotter that runs through both pins of the link
- Double cotter method, where each pin uses its own cotter
The cotters can be removed with simple tools like thin pliers and a flathead screwdriver. The process is as follows:
- Because the legs of each cotter pin are bent in different directions from each other at an angle that prevents pulling them from the pin hole you need to straighten them. Using appropriately sized pliers, carefully straighten the individual legs of the cotter pin.
- Once the legs are straightened, carefully extract the cotter pin from the chain link pin holes. You can do this with the same pliers or a flat-head screwdriver.
For more information with illustrations of the specific steps, refer to our
instructions at the following link.
Back to the Top
Shepherd's Crook (J-Hook) Cotter Pin Removal
- This cotter has a crimp in between the link pins that is necessary to minimize threading or vibrational wear when the chain is in operation. To start removing the link, use pliers to gently unbend the crimp on the cotter so it makes a straight line between the holes.
- To release the cotter pin, push it from its straight end towards the link pin hole (in the direction of chain travel) to unsnap the J-hook from the leading pin. To assist the removal process, you may pry out the hook from the leading pin using a cotter pin removal tool.
- Once the hook is unsnapped, slide the cotter out from both pins and proceed to Step 5.
Back to the Top
Z Style Cotter Pin (Solid Long Cotter) Removal
- Use pliers or specialty tools to carefully straighten one of the bent ends of the cotter pin; there is no need to straighten the other end.
- Slide the cotter pin out in the direction of the bent end.
- Once the cotter is removed, proceed to Step 5.
Back to the Top
How to Remove a Riveted Chain Pink Link
You may find advice suggesting hitting the pin rivets with a hammer until the rivet head is flat with the side plate. We do not recommend using this method because it's unsafe and may cause collateral damage. Instead, you should use an angle grinder tool to carefully grind off the link pin rivet heads.
Before you start, ensure you have appropriately fastened the chain link on a workbench or a sprocket (Step 3).
- Turn on the grinder and gradually increase the speed to a comfortable working level. Hold the grinder firmly with both hands and maintain good control over the tool.
- Focus on removing material gradually. Grind the rivet head in incremental bursts.
- Aim to grind off the rivet head flush with the surface of the side plate.
- Precision is key. Avoid excessive grinding that could damage the side plate itself.
- Repeat the process for the second pin.
Cautions:
- When grinding the rivet head with the chain secured to the sprocket, ensure there's ample clearance between the grinder disc and other components to avoid accidental contact and damage.
- Because grinding can generate heat, take short breaks to allow the chain and grinding disc to cool down and prevent overheating.
Back to the Top
Step 5: Detach the Side Plate
The final step in removing a chain link is to push the side plate off the pin links. This step will require pressing tools or a hammer and punches.
Although you may still resort to using the
hammer and drift punch method, our recommendation is to use a chain breaker tool as the safest and most effective method.
Removing a chain link
without the tools is only possible when the side plate is slip-fit on the chain link pins.
Back to the Top
Use Pressing Equipment to Drive the Pins Off the Side Plate
Pressing equipment allows for the application of steady force on the press-fit link pins. It minimizes the chances of the link parts cracking and particles of metal chipping off and striking the operator. Therefore, using pressing tools to disconnect the side plate from the pins is
the preferred method. It not only minimizes the risks of operator injury or damage to equipment, but it has also proven to be the least laborious and require less skill and training compared to the hammer and drift punch method.
There are different configurations of pressing tools and equipment available commercially. One tool that has proven to be highly efficient is a
chain breaker tool. This is a specialized chain breaker tool designed for removing press-fit side plates on roller chains. Its different size options are built to handle the forces required for the side plate removal task and minimize damage to chain components. The most common chain breaker tool has a hand-held design, however, bench-mount chain breakers are also available.
When working with a press-fit roller chain, it's essential to select the correct chain breaker tool made for that particular chain type. Using the wrong tool could result in damage to both the chain and the tool itself. To avoid this, ensure that the tool is specifically
designed for press-fit links and is compatible with the size and specifications of your chain. Please use our recommendation on selecting the right size of the chainbreaker tool.
The overall process of using a chain breaker tool is relatively simple and involves securely placing the tool on the chain link and driving the pins out until they disengage from the side plate. For a more detailed breakdown of the steps and other information, please use the guide referred earlier:
Back to the Top
Remove the Side Plate Using a Hammer and Punch
Although we generally don't recommend punching out the pins because this method is more laborious and less safe, you may still apply it at your discretion after
you receive some training in working with a hammer and punches. It is critical that safety goggles are used during the process, and only personnel qualified and experienced in chain handling should perform this task.
Another limitation of this method is that it is primarily
used on a workbench. You need to secure the chain in a vise or another type of restraining equipment, and it is not always feasible when you are working with a chain on a drive unless the space provides enough amplitude and the correct angle of application. Using this method on a chain installed on equipment is not recommended due to potential damage to the equipment.
What you will need use this method right:
- A vise
- A soft-faced hammer
- A drift punch or pin punch out tool
- PPE*
*As with any other chain link removal operation, you need PPE, but we can't stress enough the importance of safety glasses to protect your eyes from flying debris for this particular method.
Here is the process:
- Make sure you have completed Step 3 and clamped the chain section in a vise.
- Position the punch or pin punch tool in the center of the grinded pin surface, aligning it precisely to avoid bending the plate.
- Using the hammer, apply minimal force with gentle blows on the punch to push the side plate off the pin, and avoid forceful blows.
If you are using this process to
remove a link from a multi-strand roller chain, after pushing the chain pins through the side plate holes, continue pushing them through the bushings of the first strand. Repeat this step through the second and subsequent strands.
Back to the Top
© USA Roller Chain & Sprocket. Any unauthorized publishing is prohibited.
Disclaimer: This guide reflects a private opinion. We cannot be held accountable for any damage or injury resulting from chain link removal based on this guide only. It was created for trained professionals in the field to share our insights and perspectives on improving the safety and efficiency of the link removal process. It is an enhancement to already existing instructions and recommendations provided by chain manufacturers and professional associations and does not substitute them. This guide is invalid in any instance that contradicts such instructions and recommendations.
|