Screw extractor

The DIAGER U505 screw extractor set is designed to remove broken, worn, or damaged screws and bolts during machine assembly and maintenance. The U505 range offers four versions from 5 pieces to 8 pieces, each numbered to correspond to different metric screw diameter ranges.

The extractors are manufactured from high-quality steel with special left-hand threads that, when turned clockwise, bite firmly into the broken screw shaft and create reverse torque to remove the screw from the threaded hole. The square shank allows secure clamping into wrenches or sockets, ensuring stable torque transmission.

The 5-piece set U5050153 suits basic needs with small and medium screws, the 6-piece set U5050163 adds extractor number 6 for larger bolts, while the 8-piece sets U5050183 and U505 cover the entire range from small screws on electronic devices to industrial machine frame bolts. Each set comes in a compact plastic case, easy to carry to workshops or construction sites. Diager.vn distributes the genuine U505 range with full EAN codes and manufacturer warranty.

Removing broken bolts is a necessary technical operation when screw or bolt heads break, threads wear, or damage occurs during machine assembly and maintenance. This situation often happens due to over-torquing, metal corrosion, or strong impacts that deform the screw head. In such cases, screw extractors with special left-hand thread design help remove the remaining screw portion without damaging the threaded hole in the machine part.

The DIAGER U505 screw extractor range provides sets from 5 pieces to 8 pieces, each numbered to correspond to different metric screw diameter ranges. These sets are manufactured from high-quality steel, with square shanks for secure clamping into wrenches or sockets, ensuring stable torque during removal. Users can choose the 5-piece set U5050153 for basic needs with small and medium screws.

The 6-piece set U5050163 when needing extractor number 6 for larger bolts, or the 8-piece sets U5050183 and U505 to cover the entire diameter range from small screws on electronic devices to industrial machine frame bolts. Each set comes in a compact plastic case, easy to carry and store at workshops or construction sites.

Operating principle of screw extractors

Screw extractors operate based on the principle of left-hand threads, opposite to conventional threads. When turning the extractor clockwise, the left-hand thread bites firmly into the broken screw shaft and simultaneously creates reverse torque to remove the screw from the threaded hole. Before use, the technician needs to drill a small pilot hole at the center of the broken screw portion, then select an extractor of appropriate size for the screw diameter.

The extractor is attached to a wrench or socket through the square shank, ensuring secure clamping to transmit torque evenly. When turning gently and steadily, the left-hand thread will bite deep into the broken screw metal and pull it out without damaging the hole threads in the machine part. This method saves time and cost compared to having to drill out the entire threaded hole and re-machine it.

All DIAGER U505 screw extractor sets use high-quality steel to withstand high torque without breaking or wearing quickly. The square shank on each extractor helps users clamp securely into sockets or hand wrenches, preventing slippage when applying force. The special left-hand thread design is precisely machined to bite firmly into the broken screw shaft from the first turn. As a result, the screw removal operation becomes safer and more efficient, especially in situations where screws are rusted or stuck for long periods.

Classification of screw extractor sets by piece count

The DIAGER U505 screw extractor range is divided into 5-piece, 6-piece, and 8-piece sets, each serving different screw diameter ranges. The 5-piece set suits basic needs in household equipment and small workshop maintenance, while the 6-piece and 8-piece sets expand the capability to handle larger bolts on industrial machinery. Choosing the appropriate set helps users save investment costs while ensuring sufficient tools for common situations.

The 5-piece screw extractor set U5050153 includes extractors numbered 1 to 5, covering small and medium metric screw sizes commonly found on electronic devices, woodwork, and light machinery. This set comes in a compact plastic case, easy to carry when moving between construction sites or storing in tool cabinets. The 6-piece set U5050163 adds extractor number 6 to handle larger diameter bolts, commonly found on machine frames or steel structures. This is a balanced choice between coverage and cost for small and medium mechanical workshops. The 8-piece sets U5050183 and U505 provide the most complete range from extractor number 1 to 8, covering the entire metric screw range from the smallest to industrial machine frame bolts, suitable for professional repair workshops or factories with many types of equipment.

How to choose the right screw extractor set

When selecting a screw extractor set, users need to clearly identify the screw diameter range frequently encountered in their work. If working mainly with electronic devices, woodwork, or light machinery with small and medium metric screws, the 5-piece set U5050153 will meet needs sufficiently without excessive cost. For small and medium mechanical workshops frequently repairing machinery with larger bolts, the 6-piece set U5050163 provides extractor number 6 to handle more difficult situations. Professional repair workshops or factories with many types of equipment should invest in the 8-piece set U5050183 or U505 to be ready to handle all broken screw sizes without having to purchase additional tools later.

Besides piece count, users also need to check material and shank design. All DIAGER U505 sets use high-quality steel and square shanks, ensuring durability and stable torque transmission capability. The compact plastic case helps with storage and easy carrying, preventing extractor loss when moving between construction sites. Choosing the appropriate set not only saves costs but also increases work efficiency, reducing downtime when encountering broken screws during repairs.

Practical applications in maintenance and repair

Screw extractors are widely used in automotive, motorcycle, industrial machinery, and household appliance maintenance. In automotive workshops, bolts on suspension systems, engines, or chassis often rust and break when disassembling. Screw extractor sets help mechanics remove them quickly without having to drill out threaded holes, saving time and replacement part costs. In industrial machinery repair, bolts on machine frames or transmission systems may break due to high loads or long-term vibration. The 8-piece sets U5050183 or U505 provide sufficient sizes to handle from small screws on control panels to large bolts on steel frames.

In electronics and woodwork, small screws often have worn threads or broken heads when over-tightened or using inappropriate screwdrivers. The 5-piece set U5050153 meets this need well with small extractors from number 1 to 5, helping remove broken screws on computer cases, household appliances, or furniture without damaging surfaces. For small and medium mechanical workshops, the 6-piece set U5050163 provides extractor number 6 to handle larger bolts on lathes, milling machines, or lifting equipment, ensuring flexibility in various repair situations.

Notes when using screw extractors

Before using a screw extractor, the technician needs to drill an accurate pilot hole at the center of the broken screw portion. This hole must be straight and deep enough for the extractor to bite firmly into the screw shaft, avoiding off-center alignment that causes uneven left-hand thread engagement and may break the extractor. The pilot hole diameter should be smaller than the screw thread core diameter to leave enough metal for the left-hand thread to bite into. After drilling, clean chips and dust with compressed air or a soft brush, ensuring the contact surface between extractor and broken screw is not obstructed.

When turning the extractor, apply force evenly and gently, avoiding excessive force or jerking. If the extractor feels stuck or cannot turn, stop and recheck the pilot hole or try an extractor of different size. Using lubricating oil or anti-rust solution can help reduce friction and increase the ability to remove rusted screws. After use, clean the extractor and store it in the plastic case to avoid impacts or corrosion, ensuring durability and accuracy of the left-hand thread in subsequent uses.

The DIAGER U505 screw extractor sets provide effective solutions for various repair situations. Users can start with the 5-piece set U5050153 for basic needs, upgrade to the 6-piece set U5050163 when needing to handle larger bolts, or invest in the 8-piece sets U5050183 and U505 to be ready for all broken screw sizes in professional workshops.