Spanner Types and Uses UK

Spanner Types and Sizes in the UK

There are actually 10 different types of spanners. I have shown a list below, and then explained each type, along with a picture so as you can quickly and easily see the difference. You can buy these as a single spanner, but they are mainly sold in sets of different sizes.

1. Open-ended spanners
2. Ring spanners
3. Offset ring spanners
4. Combination spanners (Combi spanners)
5. Flare Nut Spanners
6. Socket spanners
7. Ratchet spanners
8. Adjustable Spanners
9. Box Spanners
10. Torque Wrenches

The table below compares each type, what sizes are available, and what they are best used for. Underneath the table I go into more detail of each with images to make recognition easier.

1. Open-ended Spanners

These take their name as the ends of the spanner are open. (Not closed in) They have two open jaws, usually slightly different in size (one 2mm smaller than the other). That simply means the spanner will be able to turn 2 different sized nuts and bolts. The jaws fit around the head of a nut or bolt, allowing you to grip it from two sides.
They come in various sizes, typically ranging from 6mm to 32mm in the UK market, available as individual spanners or in sets.

Main Uses

• Open-ended spanners are ideal for quick jobs and situations where limited access is an issue.
• Their simple design makes them easy to use and maneuver in tight spaces.
• They're perfect for tasks like tightening furniture bolts, loosening drain plugs, or assembling basic DIY projects.

Benefits

• Open-ended spanners are relatively inexpensive and easy to find in any hardware store in the UK.
• They work with a wide range of nut and bolt sizes and shapes.
• The open design allows for fast access and turning without removing the spanner completely.

2. Ring Spanners

These take their name as the ends of the spanner are closed in a ring shape. That allows them to fit snugly around the entire nut or bolt head. This ring comes in various sizes, typically matching the open-ended spanner range (6mm to 32mm in the UK) and available individually or in sets.

Main Uses

• Ring spanners are best in situations demanding secure grip and precision. Their enclosed head prevents slipping and provides better leverage for high-torque tightening or loosening.
• They're ideal for tasks like assembling furniture with critical joint connections, working on engines or machinery, or any application where accuracy and controlled force are crucial.
• Compared to open-ended spanners, they are:

1. Less prone to slippage and rounding off nut edges.
2. Makes tightening and loosening easier, especially for high-torque situations.
3. Can sometimes reach nuts in confined spaces due to the enclosed head design.

Benefits

• Ensures controlled turning and prevents accidental slippage.
• The enclosed head protects the nut and spanner from damage.
• Works with various nut and bolt shapes and sizes

3. Offset Ring Spanners

Offset ring spanners are like the special forces of the wrenching world, tackling nuts and bolts where their straight-on normal ring spanners simply can't reach. Unlike regular ring spanners with their straight heads, offset ring spanners have heads bent at an angle (usually 15° or 75°). This bend allows them to access nuts and bolts in tight spaces where a straight spanner would hit obstacles like pipes, beams, or other components. They come in the same size range as regular ring spanners (typically 6mm - 22mm in the UK) and are usually available individually or in dedicated sets.

Main Uses

• Working on car engines or machinery with congested compartments.
• Disassembling furniture with hidden nuts tucked away in tight corners.
• Reaching nuts behind pipes or cables in plumbing and electrical work.
• Any situation where a straight ring spanner would hit an obstacle, preventing access.

Benefits

• The angled head grants access to nuts in impossible-looking spaces, saving frustration and time.
• Similar to regular ring spanners, they offer a secure grip and controlled turning for accurate tightening or loosening.
• The enclosed head protects the nut and spanner from damage, even in tight spaces.

4. Combination Spanners

Combination spanners, also known as combi spanners in the UK. This type of spanner has one open end and a ring end, and hence the name a combination or combi spanner. One end features an open jaw, similar to an open-ended spanner, allowing for quick access and turning.

The other end boasts a fully enclosed ring head, resembling a ring spanner, providing secure grip and precision tightening or loosening.
Combination spanners typically come in the same size range as their individual counterparts (6mm - 32mm in the UK) and are available individually or in convenient sets.

Main Uses

• Use the open end for fast access and turning, like tightening loose nuts.
• Switch to the ring end for secure grip and controlled tightening or loosening when more force is needed.
• The compact design allows them to fit in tight spots where separate open-ended and ring spanners might struggle.
• Carrying one combination spanner eliminates the need for two separate tools, saving space and weight in your toolbox.

Benefits

• Two tools in one, offering both fast access and secure grip for varied tasks.
• Reduces tool changes and saves time during projects.
• Ideal for carrying around or working in tight spaces.
• Buying one combination spanner is often cheaper than purchasing separate open-ended and ring spanners of the same size.

5. Flare Nut Spanners

These specialised spanners have U-shaped jaws with rounded edges designed to grip and turn flared nuts commonly found in plumbing and gas lines. Unlike regular spanners, their jaws have rounded edges to prevent damage to the delicate flare, ensuring a leak-free seal.

Flare nut spanners are essential tools for plumbers, gas engineers, and DIY enthusiasts working with gas and fluid lines. While not everyday tools, their ability to protect delicate flared nuts and ensure leak-free connections makes them invaluable for specific tasks.

Main Uses

• Tightening and loosening flared nuts on gas pipes, brake lines, refrigeration systems, and hydraulic lines.
• Preventing damage to the flared edges, essential for maintaining leak-free connections.
• Working in tight spaces where regular spanners might struggle due to their bulkier design.

Benefits

• Their design minimises the risk of rounding or damaging the delicate flare, essential for maintaining leak-free connections.
• The U-shaped jaws provide a firm grip on the flared nut, preventing slippage and ensuring proper torque application.
• Available in various sizes to handle different flared nut diameters commonly used in plumbing and gas applications.
• They are often slimmer than regular spanners, making them suitable for working in tight spaces.

6. Socket Spanners

Socket spanners, also known as socket sets in the UK, offer interchangeable sockets that fit onto a ratchet handle for turning various nut and bolt shapes and sizes. This modular system provides ultimate versatility in a compact kit. Socket spanners are a powerful addition to any toolbox, offering exceptional versatility and convenience.

Their wide range of applications, compact design, and interchangeable sockets make them a go-to choice for both basic DIY tasks and professional work. However, their initial cost and potential for losing small parts should be considered.

Main Uses

• They are mainly used for tightening and loosening various nuts and bolts across different tasks, from car repairs to furniture assembly.
• Reaching nuts in tight spaces due to the slim profile of sockets compared to traditional spanners.
• They can handle a wide range of nut and bolt shapes, including hex, square, spline, and torx, thanks to interchangeable sockets.
• They apply controlled torque with the help of different ratchet mechanisms (standard, quick-release, torque wrench).

Benefits

• One set covers multiple sizes and shapes, reducing the need for individual spanners.
• Sockets and handles store efficiently, saving space in your toolbox.
• Slim sockets reach tight spaces where traditional spanners struggle.
• Different ratchet mechanisms offer standard tightening/loosening, quick action, or controlled torque application.
• Sockets are typically made from strong materials like chrome vanadium steel, ensuring longevity.

7. Ratchet Spanners

Ratchet spanners combine the convenience of a ratchet mechanism with the handiness of a standard spanner, allowing for fast and efficient tightening and loosening of nuts and bolts without needing to remove the tool completely.

They are a valuable addition to any toolbox, especially for tasks requiring speed, efficiency, and minimal hand strain. Their innovative design makes them ideal for repetitive work in tight spaces. However, their initial cost, limitations in high-torque situations, and potential for losing small parts should be considered before purchase.

Main Uses

• Tightening and loosening nuts and bolts quickly, ideal for repetitive tasks or situations where access is limited.
• Working in tight spaces where hand movement is restricted, as the ratchet mechanism requires minimal back-and-forth motion.
• Applying controlled torque with some models featuring adjustable torque settings.
• Handling various nut and bolt sizes with interchangeable heads on some models.

Benefits

• The ratchet mechanism allows for continuous turning without removing the spanner, saving time and effort.
• Slim profiles often fit in tight spaces where regular spanners might struggle.
• Minimal hand movement required, minimising fatigue during repetitive tasks.
• Adjustable torque settings on some models ensure proper tightening without overdoing it.
• Interchangeable heads on some models offer the flexibility of multiple spanner sizes in one tool.

8. Adjustable Spanners

These handy tools feature a sliding jaw that adjusts to various nut sizes, eliminating the need for a whole set. They're great for quick fixes and odd jobs but not ideal for high-torque applications. They are often referred to as "adjustable wrenches" or "shifting spanners," and the name given varies in different regions in the UK, and indeed throughout the world.

Adjustable spanners are valuable tools for versatility and convenience, particularly for basic tasks or situations where multiple sizes are needed. However, their limitations in precision, torque, and potential for wear should be considered when tackling demanding jobs or requiring high accuracy. They are best used as a complement to dedicated spanners for specific sizes and best performance.

Main Uses

• Used for tightening and loosening nuts and bolts of various sizes, particularly useful when dealing with unknown or mixed sizes.
• Really handy for quick adjustments and repairs where carrying a full spanner set might be impractical.
• Can be used for working in tight spaces where bulky individual spanners struggle to fit.
• They serve as an excellent backup tool when the exact size spanner is unavailable.

Benefits

• Adapts to various nut and bolt sizes, reducing the need for multiple spanners.
• One tool does the job of many, saving space in your toolbox.
• Quick adjustments eliminate the need to switch between different spanners.
• More affordable than purchasing individual spanners for various sizes.
• Can sometimes handle bolts and nuts with slightly irregular shapes.

9. Box Spanners

Box spanners, also known as box-end wrenches, feature fully enclosed heads that envelop the entire nut or bolt head, offering exceptional grip and leverage for high-torque applications in demanding tasks. Box spanners are essential tools for tackling high-torque jobs and stubborn nuts and bolts where regular spanners fall short.

They have a very robust design, exceptional grip, and the leverage they deliver make them ideal for professionals and DIY enthusiasts working on demanding tasks. However, their bulkiness, limited size range, and higher cost should be considered before purchase.

Main Uses

• Tightening and loosening large nuts and bolts requiring high torque, ideal for car repairs, machinery maintenance, and heavy-duty projects.
• Working with stubborn or seized nuts and bolts where regular spanners might struggle.
• Applying controlled torque with some models featuring torque wrench functionality.
• Reaching recessed nuts and bolts due to the slim profile of the box head.

Benefits

• Enclosed head prevents slippage and ensures maximum torque transfer, even on worn or damaged nuts.
• Long handles and deep box heads provide increased leverage for tackling tough jobs.
• Robust construction withstands high forces and demanding environments.
• Adjustable torque settings on some models ensure proper tightening without overdoing it.
• Can sometimes reach recessed nuts and bolts inaccessible to regular spanners.

10. Torque Wrenches

Torque wrenches are specialised tools that apply a pre-set amount of torque to nuts and bolts, ensuring they are tightened to the correct specification with utmost precision. This prevents overtightening or under tightening, crucial for safety and optimal performance in critical applications. They are invaluable tools for anyone working on tasks where precise torque application is crucial.

While they are an investment, the benefits of preventing damage, ensuring safety, and achieving the best performance often outweigh the cost. However, their specialised nature, calibration requirements, and potential for misuse should be considered before purchase.

Main Uses

• Tightening critical components in engines, machinery, automotive repairs, and other situations where precise torque is essential.
• Preventing damage to delicate components that can occur from overtightening.
• Ensuring consistent and reliable performance by applying the manufacturer's recommended torque specifications.
• Verifying the tightness of existing bolts, especially in safety-sensitive applications.

Benefits

• Eliminates the risk of over or undertightening, ensuring optimal performance and safety.
• Consistent torque across multiple fasteners, guaranteeing reliable results.
• Protects delicate components from damage caused by excessive force.
• Ensures you're following manufacturer recommendations for proper assembly and maintenance.
• Available in various types (click, digital, beam) and torque ranges to suit different applications