If you’re reading this, chances are you’ve run up against AS1252 bolts before—whether you’re an industrial maintenance tech, a construction foreman, a hobbyist building heavy machinery, or even someone stuck with a stubborn bolt on a weekend project. I’ve been on the supply end of AS1252 bolts for over a decade now, and I can’t tell you how many times I’ve fielded panicked calls from customers who messed up an extraction because they skipped a simple step, or tried to use the wrong tool, and ended up damaging the bolt, the workpiece, or (worse) themselves. AS1252 isn’t just any old bolt series—they’re designed for high-torque applications, from heavy equipment frames to structural steel bridges, so they’re built to hold tight. That same toughness, though, makes them a bear to remove if you don’t know what you’re doing. Today, I’m walking you through the safe, proven steps I’ve shared with our customers over the years, no sketchy hacks or unnecessary risks. AS1252 Bolts Series
First, let’s start with why safety and preparation matter more than speed. I’ve seen a tech yank a wrench too hard, slip, and crack a gear housing; I’ve seen a DIYer use a torch on a bolt that was holding a propane tank (that ended way worse than the bolt). AS1252 bolts are made from medium-carbon or alloy steel, hardened to withstand extreme stress, so brute force rarely works. Rushing past prep steps just turns a minor removal job into a repair or injury. Before you touch a single tool, take 10 minutes to confirm two things: the workpiece is stable, and you know what you’re working with. If you’re on a construction site, chock the area under the steel beam or heavy equipment frame so it doesn’t shift while you work. If you’re indoors, clear a 2-foot radius around the bolt to avoid knocking over tools or parts if something slips. Also, double-check that this is actually an AS1252 bolt—their markings are standard: a series number stamped on the head, usually followed by a size code like M20 or 3/4”. If you’re not sure, cross-reference with our spec sheets (we have them free on our portal for all our customers) before you start.
Next, the most common mistake I see people make is ignoring the thread treatment and corrosion that AS1252 bolts often have. Because these bolts are used in outdoor or high-moisture environments, they’re almost always coated—zinc, hot-dip galvanized, or even painted for structural jobs—plus years of exposure to dust, rain, or construction debris can cause the threads to seize up. Seized threads are why a bolt that turned smoothly when it was installed suddenly won’t budge after 5 years. The fix here is penetrant lubricant, and not just any old WD-40. Wait, hold on—WD-40 is a lubricant, but it’s not designed for deep thread penetration, especially on hardened steel. We recommend a high-quality penetrant like PB Blaster or Liquid Wrench’s heavy-duty formula, which has solvents that eat through rust and break the friction between the bolt’s threads and the hole. The trick here isn’t spraying it once and walking away: apply the penetrant evenly to the bolt head and around the base, then let it sit. For standard seized bolts, 15 to 20 minutes is enough, but if the bolt is in a wet, outdoor spot, give it an hour—even overnight if it’s really bad. You can also gently tap the side of the bolt head with a small mallet (never a sledgehammer, that’ll crack the head) to help the penetrant seep deeper into the threads; the tiny vibrations loosen rust particles that the spray can’t reach.
Once the penetrant has done its work, it’s time to pick the right tool for the job. This is another area where people cut corners, and it almost always leads to a damaged bolt. AS1252 bolt heads are typically 6-point hex or 12-point, and you need a socket that fits perfectly—no half-measures. A socket that’s even 1/32” too small will round off the edges of the bolt head, turning a manageable removal into a nightmare. I’ve had to rush replacement AS1252 bolts to customers who tried to use a worn-out socket and rounded the head so bad they had to drill it out, which added hours to their project (and cost them more money). So, check the bolt head’s edges with a caliper or a new socket first. For most AS1252 applications, a 1/2-inch drive impact wrench is ideal—but only if you use the right setting. Impact wrenches deliver sudden, high torque, which is great for seized bolts, but if you set it to max torque, you can snap the bolt right off at the thread. Start with a medium setting, reverse the wrench, and let the tool do the work; you don’t need to push or pull hard on the handle. If you don’t have an impact wrench, a ratchet with a long handle works too—longer handle means more leverage, so you don’t have to apply as much force. Never use a breaker bar with a cheater pipe longer than 2 feet, though; that’s a recipe for applying too much torque in one spot, again risking a broken bolt or a slipped wrench.
Wait, what if the bolt is still stuck even after all that? This is when people start jumping to the worst options: torching the bolt head, or drilling into it. I get why they do it—frustration makes you want to solve the problem fast—but both of those methods are high-risk and can damage the workpiece. Torching, for example, generates extreme heat that can warp metal around the bolt, like a nearby pipe or a structural beam, and if you’re working near flammable materials (gas lines, insulation), that’s a fire hazard. Drilling is less dangerous but requires precision: if your drill bit is off-center, you’ll damage the internal thread in the hole, which means you have to re-tap the entire hole (a job that takes special tools and know-how). Instead, I recommend two safer, more targeted options. The first is a bolt extractor kit, specifically made for AS1252 series bolts. These kits have a hardened steel bit that fits into the center of a bolt head (you drill a small pilot hole first, only 1/8 inch deep—no need to drill all the way through the bolt) and then an extractor that bites into the bolt when you turn it counterclockwise. The key here is using the right size pilot hole—check your extractor kit’s guide to match it to your bolt size—otherwise, the bit will slip. The second option is applying controlled heat, only to the bolt head, not the surrounding metal. If you use a torch, point the flame only at the bolt, not the workpiece, and heat it for 10 to 15 seconds, then immediately apply more penetrant and try turning it. The heat expands the bolt’s head and threads, breaking the rust seal. This works, but only if you take care to keep the heat off nearby materials that could be damaged.
Let’s also talk about what to never do when removing AS1252 bolts, because these are the mistakes I see the most often. First, never use a regular drill bit to drill a seized bolt without a pilot hole. That’s how you slip and ruin the thread, leading to extra work and replacement parts. Second, never weld a nut to the seized bolt head to get more leverage—welding can warp the bolt, and if the nut isn’t aligned perfectly, you’ll just pull the bolt straight, breaking the shank off in the hole. Third, never skip wearing personal protective equipment (PPE). Even if it’s a small bolt, a loose shard of broken steel can fly at your face, or a wrench can slip and hit your hand. Wear safety glasses, work gloves, and steel-toe boots every single time you work with these bolts. Fourth, don’t use a hammer on the socket or bolt head. Tapping a bolt head with a mallet is fine, but a steel hammer on a socket can bend the socket’s edges or chip it, making it useless for future bolts.
Now, what if you’re removing an AS1252 bolt that’s broken flush with the workpiece? That’s a specific case that our team gets questions about all the time. In this scenario, you can’t use a socket or a bolt extractor that fits over the head, so you need to use a different tool. Start by marking the exact center of the broken bolt with a punch, then drill a pilot hole as deep as the bolt’s core. Once you have the pilot hole, tap in a left-handed drill bit—these bits turn counterclockwise, so when they catch on the bolt’s threads, they’ll pull the broken bolt out as you drill. If that doesn’t work, you can use an easy out tool, which is designed for flush broken bolts, but again, take it slow. If you force the easy out, it’ll break inside the hole, making an already bad problem worse.
At the end of the day, the most important rule for removing AS1252 bolts safely is patience. I’ve been in this industry long enough to know that 10 minutes spent prepping, using the right tool, and taking it slow saves you hours of repair work, and keeps you safe. If you’re working on a big project, or you’re not confident in any step of this process, don’t hesitate to bring in a professional. We supply AS1252 bolts to contractors, maintenance teams, and DIYers across the country, and we pride ourselves on not just selling quality parts, but helping our customers use them correctly. If you have questions about AS1252 bolt sizes, removal tips, or need a replacement bolt for a stuck one, we’re here to help. You can reach our team to discuss your project, get custom quotes, or ask any technical questions—we’re happy to walk you through every step to make sure your project goes smoothly.
A193 Hex Bolts Series References
- Machinery’s Handbook, 31st Edition, Industrial Press, 2020, Section on Fastener Removal and Corrosion Mitigation
- ASME B18.2.1, Standard for Hex Screws and Bolts, American Society of Mechanical Engineers, 2022, Section on AS1252 Series Bolt Specifications
- Fastener Safety and Best Practices, Occupational Safety and Health Administration (OSHA), 2021, Technical Reference Guide for Industrial Maintenance Work
- Practical Bolt Extraction Techniques, Society of Manufacturing Engineers (SME), 2019, Tutorial on High-Torque Fastener Removal for Industrial Applications
Ningbo Taida Fastener Manufacture Co., Ltd.
Ningbo Taida Fastener Manufacture Co., Ltd. is well-known as one of the leading as1252 bolts manufacturers and suppliers in China. Please feel free to buy high quality as1252 bolts at competitive price from our factory. Good service and punctual delivery are available.
Address: No.286 Galaxy Road, Chengdong Industrial Park, Xiangshan Economic Development Zone, Ningbo China
E-mail: suki@tdfasteners.com
WebSite: https://www.td-fasteners.com/
