How to clearly describe a magnet procurement requirement
-How to communicate needs with magnetic material sales staff?
-What details must be clarified to obtain accurate quotes and delivery dates?
If you have such doubts in the purchase of magnetic materials, then today's article will definitely help you.
The purchase needs of magnets are mainly divided into two parts, one is the basic requirements for magnets, and the other is the requirements for project delivery dates.
Basic requirements for magnets
When we want to clearly explain the purchase needs of a magnet, there are several major key points that need to be clarified: performance requirements, shape and size, magnetization direction and surface treatment requirements. The purchaser is best to provide drawings of the magnet. Below we take NdFeB permanent magnets as an example to explain in detail.
1. Performance requirements:
that is, the grade requirements of the magnet. There are many suppliers in the magnetic material industry, and each company has different definitions and performance ranges for the same grade. When communicating the grade, it is recommended that both the supply and demand parties clarify the remanence Br and intrinsic coercive force Hcj of the corresponding grade, so that it is not easy to cause deviations. (If the purchaser is not clear about the product brand, then some auxiliary judgment indicators need to be provided, such as surface magnetism, tension, magnetic flux/magnetic moment, etc.)
In addition, according to factors such as the working environment of the magnet, indicators such as remanence and coercive force temperature coefficient can be further clarified.
If there are clear requirements for indicators such as magnetic flux, the detection equipment and detection method should be agreed as the judgment standard.
2. Shape, size and magnetization direction:
When describing the procurement requirements, the basic shape and size requirements of the magnet must be clear, such as 6.0mm (+0.03/-0.03). For simple products, provide basic length, width and height dimensions and tolerances; for magnets with complex shapes, the contour and other angle requirements (similar to the red mark 30°±1° in the figure below) need to be provided more clearly, and it is recommended to provide clear drawings to suppliers.
In addition, the magnet also needs to mark the product's orientation direction (NS pole) and magnetization method (single pole charging or multi-pole charging), as well as the magnetization angle, etc.
3. Surface treatment requirements:
The purchaser needs to specify the surface treatment method of the magnet, including coating method (electroplating, chemical plating, electrophoresis, vapor deposition, etc.), coating material (zinc, nickel, copper, aluminum, epoxy resin, etc.), and coating thickness.
If there are requirements for salt spray or other tests, the setting of test conditions, placement time and judgment criteria after the test must be agreed upon.
4. Other requirements:
such as: appearance requirements, other test requirements (such as aging test, etc.), packaging requirements, transportation requirements, etc.
Product delivery period
Most suppliers have a stock of magnet blanks, and there is a certain reserve for general performance. The shape of the magnet roughly determines the length of the product's delivery period.
Customized products generally require special molds. If the manufacturer does not have a mold of the right size, there will be a mold production time, and the product delivery period will be extended to a certain extent.
The overall construction period can be compressed but it may not be delivered completely according to the purchaser's ideal time. For products with urgent delivery, you must place an order in advance.