Introduction to Insulated Tools

In the labor field, there are a large number of jobs that involve the risk of ccontact with electricity. From the simplest work inside our home, to large-scale jobs such as construction, all of them involve the danger of electrocution.
In general, the greatest exposure when performing these jobs occurs when performing manual tasks, since our hands statistically represent the main agent of contact between our body and conductive or electrically charged objects. If reasonable safety precautions are not taken, this risk factor can be fatal.

In order to minimize or eliminate this risk factor, tools and instruments have been designed that provide protection against electric shock. Among these are the isolated tools or insulators.

Designed and created for jobs where you must interact with energized electrical equipment or systems, insulated tools are made using special and resistant materials to protect the user in case of contact with electricity.

How is an isolated tools?

The isolated tools They have a steel base, which is covered with a thick layer of high quality and strongly adhered to the instrument, with a high dielectric level. Additionally, the plastic material coating is superimposed, which gives the final presentation to the tool, while providing an ergonomic grip.

What makes a tool to be considered “isolated”?

A first approximation is its composition. Insulated tools usually have a steel base, which is covered with a thick layer strongly adhered to the instrument, with a high dielectric level. Additionally, the plastic material coating is superimposed on it, which gives the final presentation to the tool, while providing, in the best of cases, an ergonomic grip. The design of these tools allows them to be used with parts or systems whose voltage reaches 1000V. Something that we can verify with the seal of compliance with the quality standard that identifies the manufacturer.

How is an insulated tool made?

Below we will describe in broad strokes the manufacturing process, it can vary according to different parameters from factory to factory.

The first stage of manufacturing is the cold forging of the tool, for which a two-phase technological process is used that includes annealing, phosphating, and contraction of the piece.

As a second step, a special CNC turning machine is used to obtain the required size, which is in accordance with the standard.

Sanding is then carried out, cleaning the surface before chrome plating is important for the sake of quality and protection of the piece.

The fourth step is chrome plating, which provides protection against corrosion, wear and other mechanical damage. At the same time it gives the product a shiny finish.

As a final phase, the double plastification is carried out. First, the piece is subjected to degreasing in a container of acetone. It is then submerged in a special liquid that activates its adhesive property. For the plasticizing process, the piece is placed in a special chamber oven for heating, and is immediately submerged in the plastic material. Before the second layer of plastic, the piece is gelatinized in an oven at a preset temperature. Then, a second plastic coating is applied, the gelatinization process is repeated, and the final plastic material coating gives the part the final thickness of a two-layer coating.

Necessarily, for isolated tools, a quality control procedure is necessary.

How is the quality of insulated tools verified?

• Dimensions test: During this test, it must be verified that the tool complies with the measures specified in the standard.
• Impact test: This test is performed at room temperature and cold. The tool is subjected for 2 hours, at a temperature of -25 °C. This in order to reproduce the energy of an impact produced by the fall of the tool from a specific height and check that the tool does not break or crack.
• Dielectric test: this test is performed after the impact test. The tool is immersed in a humid container for 24 hours, to later verify its resistance at 10 kV, for its safe use at 1000 AC – 1500 V DC, maximum.
• Penetration test: the tool is subjected to a temperature of 70 °C for 2 hours. Then a voltage of 5 kV is applied for 3 minutes and a force of 20N is applied to the insulation simultaneously. This to check the resistance of the insulation against crushing or perforation.
• Adhesion test: the tool is subjected to 70 °C for 168 hours. The idea is to check the adherence of the insulating material to the tool.
• Flame Spread Test: the insulated area of ​​the tool is exposed to a controlled flame for 10 seconds, to check that the insulator does not spread fire.
• Mechanical test: During this test, the hardness, resistance to bending, torsion and cutting of the tool are verified, taking into account the specifications of the standard and the manufacturer.
• Marking resistance test: The goal of this test is to validate that the tool marking is legible, no matter how much scratches it gets.

The tools that comply with the provisions of the standard must indicate it, bearing the international symbol that certifies it.

Certification of isolated tools

All insulated tools must fully comply with the provisions of the international standard “IEC 60900 – Live work. Manual tools for live work up to 1000 V in alternating current and 1500 V in direct current”. This standard established by the “INTERNATIONAL ELECTROTECHNICAL COMMISSION – IEC”, indicates the technical specifications for the manufacture of tools and details each and every one of the tests to which they must be subjected, to verify their quality and ensure that they provide the required protection. by and for the user.

The tools that comply with the provisions of the standard must indicate it, bearing the international symbol that certifies it.

Symbol for Insulated Tools that comply with IEC 60900

The implementation of these tools is common and very easy. Insulating tools, thanks to their dielectric material, prevent the electric current from coming into contact with the user’s hands, in the event of a discharge. It is important to highlight that only the part of the tool for holding or gripping has the energy insulating protection. That is why some tools provide additional protection, known as integral guards.
Integral guards function as barriers, to prevent hands from slipping and contacting the uninsulated end of the tool.

Insulated Tool with Integral Guards

Most common isolated tools

The inevitable when meeting the needs of users, in terms of jobs that require the use of isolated tools, there is a wide variety of them. Among the most used tools we find pliers, tweezers, fixed or adjustable wrenches and screwdrivers or screwdrivers.
All these types of tools have the same design and manufacturing principle already described. Depending on the brand or manufacturer, the model and color of the grip or fastening area may vary.

Considerations for the use of isolated tools:

• If possible, turn off power to the work area or equipment with which you must interact
• Only use tools that display the official international 1000V rated capacity symbol.
• When working with any of the tools, avoid making contact with the non-insulated part of it.
• Always inspect the tool before starting your work, especially check that the clamping area maintains its insulating coating in good condition.
• Do not use the tool for jobs other than those for which it was designed.
• Keep tools in good condition, clean and free of any contaminating substance.