How to Remove a Seized Conveyor Chain Pin: 4 Methods
If the chain is going back into service, press the pin out with a hydraulic chain press. Use a torch only when the chain is scrap, a hammer and punch only when the pin is tight rather than truly seized, and a grinder only when a riveted head has to come off first. Pushing a pin out of a pulled-apart chain is the same job on drag, bucket elevator, en masse, roller and engineered-class chain.
TL;DR
- Chain going back into service: a hydraulic press is the method chain makers point to. U.S. Tsubaki's guide says "Use of pressing equipment is suggested." Rexnord says grinding pins or heating sidebars "drastically decrease the fatigue strength of the chain."
- Chain being scrapped: a torch is fine. Renold's manual says a worn-out chain can be cut into handleable sections with a torch for disposal, with normal safety precautions.
- Riveted pins: the rivet head must be ground off first, whatever method you use afterward. A press does not break rivets.
- Hot work: torch cutting is hot work under OSHA 29 CFR 1910.252, and grinding falls within the scope of NFPA 51B. Both can bring authorization, fire-watch and permit work that a press step does not.
Before you start: identify what you are dealing with
Spend two minutes on this before choosing a method. Most pins that "won't move" are being pushed from the wrong side, still have a retainer in them, or have a riveted head that no tool will push through the plate.
1. Pin type and retention
| What you see on the pin ends | What it is | What it means for removal |
|---|---|---|
| Both ends mushroomed or spread over the plate | Riveted (peened) pin | The rivet head has to be ground off before the pin will pass through the plate. U.S. Tsubaki: "If the pin is taken out without grinding, it will take more time and may damage the chain." |
| One end headed, the other end cross-drilled for a cotter pin, T-pin or pin lock | Cottered pin | Remove the cotter or lock first and push the pin out from the cotter end, so the head end clears on the far side. |
| Pin head with flats, or a plate stamped "head" | Directional pin (common on engineered and elevator chain) | The pin only comes out one way. Rexnord's bucket elevator instructions say the pin "does not fit through the cotter pin side of the chain." |
Roller chain built to ASME B29.1 has its pins and bushings press-fit into the link plates. That press fit is what you are fighting, even on clean chain. Larger ANSI roller chain (No. 60 and up) comes in both cottered and riveted versions, so check every pin and don't assume.
2. Which side to push from
Push from the cotter end of the pin so the head end travels out the far side. Make sure the pin head has room to clear the cavity or relief on that far side. If you push from the wrong end you are driving the head into the plate, which is a common reason a pin "won't budge." On Rexnord drive chain with three-diameter pins, "the pin need only be pressed the thickness of one sidebar."
3. Corrosion and packed material
Renold's troubleshooting table lists the usual causes of tight or seized joints: material packed in the chain, material frozen in the joints, gummy lubricant, corrosion and misalignment. Clean packed material out of the joint and soak the pin with penetrating oil before you load it. Heavy pitting or rust on the plates is a reason to replace the section rather than reuse it. Renold says never reuse a damaged chain or chain part.
4. Pin size, if you are considering a portable press
Measure the pin diameter and the overall pin length, head to head. Portable presses have hard limits. The Kingpin works on any chain whose pins are 1.125 in. diameter or less and 2.25 in. to 7.8 in. long. Some heavy welded steel chains use larger pins. Allied-Locke's WHX6121 welded steel drag chain, for example, uses a 1.25 in. diameter pin that is 9.75 in. long, per its catalog listing, which is outside both limits.
Prep that applies to every method
These steps come from Renold's and U.S. Tsubaki's maintenance guides:
- Lock out the drive. Isolate all power before any work starts.
- Identify the chain and have replacement links on hand before you break it.
- Slacken the take-up completely so the joints are loose.
- Stop the sprockets from rotating, especially on inclined conveyors or elevators.
- Restrain the chain on both sides of the joint. On an elevator, secure the chain so it can't fall down inside the casing.
- Wear eye protection and gloves. Tsubaki requires safety glasses, protective clothing, gloves and safety shoes when connecting or disconnecting chain.
The four methods compared
The time ranges are our estimates, not field-measured data. They cover one seized pin on large chain that is already locked out and slack.
| Torch (oxy-fuel) | Hammer and punch | Angle grinder + punch | Hydraulic chain press | |
|---|---|---|---|---|
| Best use | Chain being scrapped; pin too large for any press on hand | Cottered pins that are tight but not truly seized | Riveted heads that must come off before pressing or punching | Seized or press-fit pins on chain that will go back into service |
| Hot work? | Yes. Cutting is covered by OSHA 1910.252 | No flame. Steel-on-steel striking can still throw chips | Grinding falls within the scope of NFPA 51B. Many site permits list it | The press step has no flame or sparks. A riveted head still has to be ground first |
| Typical time, one seized pin (estimate) | 5–20 min at the joint, plus roughly 45 min to 2+ hr for permit, fire watch and post-work watch | 5–15 min if the pin is only tight; 30–60+ min, or no result, if truly seized | 10–30 min per pin (grind plus punch or press), plus permit time if your site treats grinding as hot work | About 2 min of press time per pin when the tool is set up correctly and the pin is within range; allow 5–15 min including setup |
| What it does to the chain | Heat changes the steel. Tsubaki: torch-cut chain "should not be reused" | Can mushroom the pin end, bend the opposite plate and shock-load the bushing. Fine when the pin is only snug | Removes the rivet head; risk of nicking the plate. Rexnord: outer link plates of the detached link may not be reused | Steady push, no heat, no impact. The pressed-out pin and its plates still follow the chain maker's reuse rules |
| Can the chain be reused? | Not the heated links. Fine for disposal | Usually yes, if no plate or pin damage | Rest of chain yes; replace the ground link | Yes; adjacent links are unaffected. Replace the pin or connecting link per the maker's guide |
| Main risks | Fire, smoldering after the job, burns, fumes; prohibited where combustible dust has accumulated | Flying chips, struck hands, eye injury, tool slipping off the pin | Sparks, wheel breakage, flying debris | Pinch points; misaligned push pin slipping or mushrooming the pin |
| People needed | Usually operator + fire watch | Often two (holder + striker) | One or two | One |
Method by method: when each is the right call
Torch cutting
When it's the right call: the chain is worn out and coming off for scrap, or the pin is bigger than any press you own.
What it does to the chain: U.S. Tsubaki says heating chain with a cutting torch "is not suggested unless absolutely necessary for removal. If cut in such a manner, it should not be reused." Tsubaki's roller chain manual goes further: remove the links immediately adjacent and do not use them again. Rexnord's bucket elevator instructions say pins "may not be warmed or ground," because it affects chain strength and the warranty.
What it costs you in procedure: Under 29 CFR 1910.252(a)(2)(iv), the area must be inspected by the person who authorizes cutting and welding before work starts, "preferably in the form of a written permit." A fire watch is required when combustibles are within 35 ft or the other listed conditions apply, and it stays at least a half hour after cutting ends. Many permit programs follow NFPA 51B, whose 2019 edition requires a fire watch of at least one hour after hot work. On or near a process covered by PSM, 29 CFR 1910.119(k) makes a written hot work permit mandatory. OSHA also prohibits cutting near accumulations of combustible dust, and while sprinklers are impaired, under 1910.252(a)(2)(vi). See chain breaking in restricted hot-work areas.
Hammer and punch
When it's the right call: a cottered pin that is tight, not rusted solid. This is a manufacturer-approved method, not a shortcut. U.S. Tsubaki's RF conveyor chain procedure is to pull the cotters, hold the head-side plate, and tap the pin out from the opposite side. Renold uses "a sharp blow with a hammer and punch" to release connecting-link pins.
When it isn't: a pin that is corroded into the bushing or plate. Repeated blows mushroom the pin end and can bend the far-side plate or crack a bushing. Always back up the plate you are driving toward, with a hole or socket under it that clears the pin.
Angle grinder, then punch or press
When it's the right call: riveted pins. Tsubaki and Renold both say to grind the rivet head flush on one side before driving the pin out. Rexnord says the same about riveted elevator chain: "it may be necessary to remove the rivet head beforehand." On riveted chain, grinding is a required first step even when you finish with a press. Rivets are not pushed or broken through the plate.
What it does to the chain: done carefully, it affects only the link you are removing. Rexnord warns that link plates must not be damaged while grinding, and that the outer link plates of the detached link may not be reused. Tsubaki says to avoid overheating the chain when grinding. Webster says grinding pins or modifying sidebar pin holes voids its warranty, so check your chain maker's rule before grinding anything you plan to reuse.
The catch: grinding throws sparks. Rexnord says "there is a risk of fire and injury as the result of flying sparks." NFPA 51B's scope includes grinding, so many sites run it under the same hot work permit as a torch.
Hydraulic chain press
When it's the right call: the chain is going back into service, the pin is seized or a heavy press fit, or the area does not allow flame. This is the method chain makers' own guides lean toward. Rexnord sells the Linkmaster for elevator and engineered chain and says the tool means "It's no longer necessary to grind pins or heat sidebars," practices it says "have been the reason for many chain failures."
What it does to the chain: the force is a steady push along the pin axis. There is no heat-affected zone and no impact load on the bushing. A press does not change the reuse rules for the pin you remove. Rexnord says pins damaged during removal must be replaced, and Tsubaki says roller chain link plates cannot be used again once the pins have been removed. Plan on a new connecting link or pin. The links on either side are unaffected.
Limits to know: a portable press only works within its pin diameter and length range. A riveted head still has to be ground off first. A press does not remove the lockout, restraint and PPE steps above.
Step by step: removing a seized pin with the Kingpin
This is T&D Machine's disassembly sequence for the Kingpin, with the general practice from chain makers' guides added. Follow the instructions and precautions that ship with the tool.
- Lock out, slacken, restrain. Isolate power, take all tension off the take-up, block the sprockets and secure the chain on both sides of the joint. Wear safety glasses and gloves.
- Confirm the pin is in range. Pin diameter 1.125 in. or less and pin length 2.25 in. to 7.8 in. If you are unsure, call T&D Machine at 262-781-3870 before you order.
- Soak the joint. Apply penetrating oil to cut friction from dirt or rust buildup.
- Remove the retainer. Pull the cotter pins or pin locks. If the pin is riveted, grind the rivet head off first. The Kingpin does not break rivets.
- Choose the pin cavity, push pin and spacers. Pick the combination so the tool fits snugly around the ends of the pin. For either assembly or disassembly, you want minimal space between the push pin and the chain pin. As a rule of thumb, set it up with roughly a 1/8 in. (about 0.125 in.) gap between the push pin and the pin head.
- Connect the pump hose to the cylinder and tighten the coupler. Close the relief valve on the hand pump (clockwise).
- Position the tool. Set the pin cavity flush against the sidebar, with all three cavity walls touching the sidebar. Place the saddle on top of the chain roller, adjusting saddle height if needed, and center the push pin on the chain pin.
- Pump. Apply pressure with the hand pump (or the optional foot pedal). Keep the push pin square on the end of the pin and make sure the head end will clear the pin cavity on the opposite end.
- If the pin stops moving, stop pumping. Strike the chain's sidebar with a mallet, not the tool. The shock travels through the chain and can loosen the pin so you can continue. If your area restricts impact tools, use another approach (see restricted hot-work areas).
- Release and remove. When the pin pops free of the sidebar press fit, open the relief valve, let the cylinder return, and remove the pin.
- Inspect and replace. Replace the pin or connecting link per the chain maker's guide, check the bushing and adjacent plates for cracks, and confirm the rejoined joint flexes freely.
T&D Machine states about two minutes of press time per pin on pins within the advertised range, when the tool is set up and used correctly.
Kingpin specifications (from kingpinbreaker.com)
| Spec | Value |
|---|---|
| Hydraulic force | 15-ton cylinder, hand pump (foot pedal available) |
| Pin diameter | 1.125 in. and below |
| Pin length | 2.25 in. to 7.8 in. |
| Weight | 28 lb, self-contained, no external hydraulic unit |
| Dimensions | 16.5 in. x 2.5 in. x 16 in. |
| Included | 2 pin cavities, 4 push pins, 5 push pin spacers |
| Chain types listed | Drag conveyors, bucket elevators, en masse conveyors, roller chain conveyors, engineered class chain, agricultural conveyors |
| Stated pin removal time | About 2 minutes, per T&D Machine, for pins within the advertised range with the tool set up and used correctly |
| Made by | T&D Machine Corp, Butler, WI |
| Price / lead time | Call 262-781-3870 or request a quote |
The press step uses no flame and throws no sparks, so it is not hot work in the sense OSHA's welding and cutting rules use. That does not remove your site's own work-permit, lockout or PPE rules. And if the pin is riveted, the grinding it needs first may fall under your site's hot-work program. The Kingpin has no hazardous-location rating, so check your area classification before using any tool there.
Related guides: How to break chain without a torch, How to break WH-series chain without a torch, Torch vs. press: what a seized chain pin costs, and all resources.
FAQ
Can I reuse a chain after torching a pin out?
Not the heated links. U.S. Tsubaki says chain cut with a torch "should not be reused," and its roller chain manual says to remove and discard the links immediately next to the cut. Torching is fine if the whole chain is going to scrap.
Is grinding a pin head considered hot work?
Often, yes. NFPA 51B covers grinding along with welding and cutting, and NFPA's sample hot work permit names it. Rexnord's chain instructions warn of "risk of fire and injury as the result of flying sparks" when grinding rivet heads. Check your site's permit program.
Can the Kingpin push out a riveted pin without grinding it first?
No. The rivet head has to be ground off first. The Kingpin is for removing pins from chain whose pins are within range, and it does not break rivets.
Why won't my pin move even with a press?
The most common causes:
- You are pushing from the head end instead of the cotter end.
- A cotter or pin lock is still in place.
- The rivet head hasn't been ground off.
- The far-side cavity doesn't clear the pin head.
- Dirt or rust is binding the pin. Soak it with penetrating oil, or stop pumping and strike the sidebar with a mallet.
Does it work on drag chain?
Yes, as long as the pin is within the tool's range: 1.125 in. diameter or less and 2.25 in. to 7.8 in. long. Some heavy welded drag chains use bigger pins than that.
Do I need to replace the pin after pressing it out?
Plan on it. Rexnord says pins damaged during insertion or removal must be replaced, and Tsubaki says roller chain link plates cannot be reused once the pins are removed. Use a new connecting link or pin kit from the chain maker.
When is a hammer and punch good enough?
When the pin is cottered and only tight, not corroded solid. If several solid blows don't move it, stop before you mushroom the pin end and switch to a press.
What size chain does the Kingpin handle?
Any chain whose pins are 1.125 in. diameter or less and 2.25 in. to 7.8 in. long. If you're not sure, send the chain number and pin dimensions with a quote request or call 262-781-3870 to confirm before ordering.
Next step
If you break seized pins on chain you plan to keep running, request a Kingpin quote. Include your chain type, pin diameter and pin length so T&D Machine can confirm fit.
Chain-specific pages: drag conveyor chain, bucket elevator chain, conveyor chain
Sources
Kingpin Breaker: https://kingpinbreaker.com/home and T&D Machine KingPin Instructions and Precautions
OSHA / eCFR, 29 CFR 1910.252: https://www.ecfr.gov/current/title-29/subtitle-B/chapter-XVII/part-1910/subpart-Q/section-1910.252
OSHA, 29 CFR 1910.119(k): https://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.119
NFPA 51B scope (publisher listing): https://datasheets.globalspec.com/ds/national-fire-protection-association-nfpa/nfpa-51b-standard-for-fire-prevention-during-welding-cutting-and-other-hot-work/7cb822a9-a82f-4c7a-886a-d778b8ac9e9f
NFPA 51B sample hot work permit: https://www.sanbruno.ca.gov/DocumentCenter/View/3770/HotWorkPermit---NFPA
U.S. Tsubaki, Installation & Maintenance for RS Roller Chain & RF Conveyor Chain: https://www.ustsubaki.com/wp-content/uploads/installation-guide.pdf
Tsubakimoto, Roller Chain & Sprocket Maintenance Manual: https://tt-net.tsubakimoto.co.jp/lib/manual/M_CDC_ALL_EN/book/data/all_page.pdf
Rexnord, Operating Instructions for Bucket Elevator Chains: https://www.rexnord.com/contentitems/techlibrary/documents/industrial-chain/operating-instructions-for-bucket-elevator-chains_eng
Rexnord, Linkmaster and Drivemaster brochure: https://www.rexnord.com/contentitems/techlibrary/documents/5016_brochure
Renold, Conveyor Chain Installation and Maintenance: https://www.renold.com/upload/renoldswitzerland/conveyor_chain_-_installation_and_maintenance.pdf
Webster Industries, Field Assembly of Welded Steel Chains: https://www.websterchain.com/field-assembly-of-welded-steel-chains/
Diamond Chain, ASME/ANSI standard roller chain: https://pdf.directindustry.com/pdf/diamond-chain/asme-ansi-standard-roller-chain/7201-751668.html
Allied-Locke, WHX6121 listing: https://alliedlocke.com/item/cast-manganese-and-alloy-steel-chains/fabricated-steel-drag-chains/whx6121