The spanner is a common hand tool used to tighten or loosen fasteners like nuts and bolts. They offer a tighter grip and amplify the mechanical pressure in applying torque to turn objects. The tool is typically made of metal – a hand-held shaft with a profile on one end. The profile refers to the opening of the jaw that makes contact with the fastener.
Spanners can be of various types depending on the type of job it is designed for. The shape and size head, or profile, of the spanner differs from type to type. Some of the spanners have two heads on both ends of the shaft, known as the double-end spanner. These usually include open-ended spanner, ring spanner, combination spanner, ratchet spanner, and more.
The different types of spanners are:
Open-ended Spanner
The open-ended spanner has a U-shaped opening with a fixed width to fit the nut or bolt head. The profile has two flat sides that grip on opposite sides of a fastener so you can tighten or loosen it. When an open-ended spanner is also a double-end spanner, the two heads on each side of the spanner is usually of a different size. So, one tool can be used to work with two different sizes of nuts and bolts.
Adjustable Spanner
The U-shaped opening of an adjustable spanner comes with a movable jaw. The size of the opening can be adjusted to grip over different sizes of nuts and bolts. This makes it a versatile tool to have as it can work with multiple fastener sizes. Adjustable spanners usually have a 15-degree angle between the movable jaw and the handle to allow better access.
Ring Spanner
The profile in a ring spanner comes in an enclosed loop form. Designed as a double-end spanner, the ring-shaped heads are usually offset from the handle so they can easily reach the fastener. The ring profile has a fixed width. Ring spanners are available in different sizes to fit various nuts and bolts.
Combination Spanner
Like the name says, combination spanner is a combination of an open-ended spanner and a ring spanner. It is a double-end spanner with a U-shaped opening opening on one end and an enclosed loop on the other end. Both the profiles on each end are of the same size, so a combination spanner can be used to work with only one size of fastener.
Flare nut Spanner
Flare nut spanners are designed for turning fasteners that are attached to tubes or pipes, such as vehicle brake pipes or plumbing pipes. The profile opening is similar to that of a ring spanner with a small opening cut into them. Fasteners that are inaccessible to a ring spanner can be worked upon with a flare nut spanner.
Ratchet Spanner
The ratchet spanner can either be open-ended, ring-shaped or a flare nut spanner that works on a ratchet system mechanism. It allows a fastener to turn in one direction but not the other while remaining fitted to the fastener head. The tool does not have to be removed from the head and relocated every time the limit of the turning arc is reached, thus, saving time.
Podgers
Podgers have a profiled head at one end of the shaft and a tapered spike at the other. The spike, known as a ‘drift pin’, is pushed into bolt holes of holes of two work pieces to line them up. This allows a bolt to pass through the holes easily, without being forced and damaged.
Pin Spanner
Pin spanners are designed to work with lock nuts. It works differently than a spanner, as in it does not grip the head of a fastener around the outside. Pin spanners grip the fastener by inserting two metal pins into special holes in the fastener head.
Box Spanner
Made from metal tubing, box spanners typically have two profiles, one at each end of the tube. They have hexagonal profiles and cannot be used on common fasteners. Box spanners cover the whole of a fastener head, and a 'tommy bar' is used to turn the tube-shaped spanner.
Scaffold Spanner
Scaffold spanners are used to fit and take down scaffolding used for building work. This type of spanner usually has a flexible box-shaped socket head on one or both ends of the shaft.