Valve Tags for Industrial Identification and Asset Labelling

Also known as identity tags, asset tags, barcode tags, hangar tags, valve identification plates, and valve discs.

People often start with a fixed idea of what they want for valve tags based on types they have seen or have used before for other jobs. They can also choose the cheapest option, with no thought as to the cost if one or more of the tags should fail. This guide will help you to design what is right for your project.

The type of tag you need depends on only a few factors: What information they need to communicate, what environment they will be used in, and any specific considerations, such as clean food areas and chemicals they will have to endure.

The type of content should dictate the shape of the tag.

Most valve tags and similar identifying plates display a single line of text and numbers, yet they are often designed as discs, the worst shape for most tags. The text then has to be made small to fit the disc, because otherwise the discs will be too big. The main function of these tags is to display the information clearly, so rectangular plates allow the best use of space to display rectangular lines of text. Square plates are best for displaying square QR codes. To remove sharp points, they should always have radius corners.

The environment should dictate the material.

Laser engraved plastics are a popular choice because they are cheap to make, but obviously, they will not be appropriate for high temperatures, low temperatures (they become brittle and break), and they will degrade if exposed to oils, solvents, or hydraulic fluids. They can also break too easily if impacted. If you need tags to endure in most environments, plastics are not suitable, and you should use metals such as stainless steel or aluminium.

Stainless steel tags.

Stainless steel is usually specified for valve tags that have to endure and remain readable in harsh or extreme environments. They should always be 316 grade stainless steel. The cost difference between the best and poorest material for a typical tag is only around 1p, and inferior grades of stainless steel will rust or discolour in many environments.

There is no point in specifying stainless steel for valve tags if the information on them is liable to fail. Surface prints wear or scrape off too easily, or can be otherwise damaged, leaving you with a blank or unreadable tag. Chemical etching is the preferred choice, leaving the information permanently engraved into the surface. Even after fires in excess of 1000°C, the information remains readable. The information is usually made more visible with a paint fill, but even if this becomes destroyed, the information remains readable. Laser marking of stainless steel is not suitable for tags. The heat distortion can make the plates unclear and difficult to read.

Aluminium tags.

Aluminium can be a good choice for many applications, for example where good readability is required where the use of solvents, oils, or hydraulic fluids would destroy paint fills or prints, and in marine environments. It is also suitable for high temperature environments up to 300°C, even surviving exposure to temperatures of 500°C. Anoprinted aluminium, also known as anodic printing, leaves the anodised surface intact and perfectly smooth because the graphics are created and secured inside the hard surface. Engraved aluminium is generally unsuitable for valve tags and similar identification purposes. To be readable, it requires paint fill, and paint onto aluminium is prone to failure. Engraving breaks through the protective anodised surface, allowing the underlying aluminium to corrode, which will render the valve tag unreadable. Anoprinted aluminium is unaffected by solvents, oils, marine environments, and even paint stripper. It is a particularly good choice for barcodes and QR codes.

Specific requirements for specialist industries.

Some applications require a specific type of valve tag or asset identification plate. For example, identification of baking racks for an automated production line requires tags that will be subjected to high temperature, and washed with sodium hydroxide which would destroy aluminium, so etched and unfilled 316 grade stainless steel will be required.

Even for less extreme environments, pharmaceutical and food production areas should not have plastic labels, or any paints or surface prints that could fail and contaminate the production line. Explosives manufacturing requires brass labels which will not produce sparks if impacted. Equipment washed with solvents should use anoprinted aluminium tags, also known as anodic printing. Flare tips on oil and gas rigs require etched 316 grade stainless steel that will withstand very high temperatures.

Fixing.

Most tags are fixed using wire, usually stainless steel, although copper wire can be appropriate for some environments. The fixing method should be robust enough to ensure the tags remain in position even if impacted, should not degrade as plastics may if exposed to daylight, and ideally they should remain in position even after extreme damage such as by fire.