Cooke Brothers conduct tests on all hinge ranges to determine their level of corrosion resistance and allow the hinge specifier to choose hinges with durability and longevity. Our tests are conducted to the British Standard BSEN 1670 (1998), in a temperature and humidity controlled enclosure.
Hinges are subjected to salt spray tests within the controlled environment to simulate an artificial atmosphere. Products are placed in the cabinet for a specific time period where a fine mist of salt water is allowed to 'attack' the products and identify the level of corrosion resistance that ether the base metal can stand. They are then categorised into five grades of corrosion resistance, depending on how long they are able to withstand the testing procedure, these grades are detailed below:
- Grade 0 - No defined corrosion resistance
- Grade 1 - Low corrosion resistance (24 hours of salt spray testing)
- Grade 2 - Moderate corrosion resistance (48 hours of salt spray testing)
- Grade 3 - High corrosion resistance (96 hours of salt spray testing)
- Grade 4 - Very high corrosion resistance (240 hours of salt spray testing)
- Grade 5 - Exceptionally high corrosion resistance (480 hours of salt spray testing)
A part of the testing procedure required for a hinge to be CE marked also determines its level of corrosion resistance.
Selecting the Correct Base Material
Phoenix architectural hinges are available in a choice of four base metals, you should consider the level of corrosion resistance required for the hinge application when choosing the base metal for your hinges. It is the base metal which determines corrosion resistance, not the applied finish. Mild steel is not considered to be corrosion resistant at all, even with applied finishes, you should only site hinges made of mild steel indoors.
The most corrosion resistant base metals available are the stainless steel hinges. Available in a choice of two types of stainless steel, Phoenix stainless steel hinges are thoroughly tested and guaranteed to be corrosion resistant. Stainless steel grade 304 is the most commonly used grade of stainless steel, it is suitable for use in most internal and external environments. Stainless steel grade 316 is a marine grade stainless steel, recommended for all high corrosion environments, including use in coastal regions and high humidity areas (swimming baths, etc).
In addition to the above testing for BSEN 1670 grades 0 to 5, we have also tested the stainless steel versions of the seven hinges range of products to 1000 hours of salt spray testing. As you can see from the grading table above, this is exceptionally high corrosion resistance, far exceeding the requirements to be categorised as grade 5.