The MuShield Co.

When selecting magnetic shielding materials, there are several parameters which need to be considered. The most critical is determining the strength or flux density of the magnetic field to be shielded. Other factors, such as shield geometry, required attenuation, and mechanical stability are also important. Once the field strength has been determined, either by direct measurement with a gauss meter or by mathematical modeling, the appropriate magnetic shielding alloy can be selected. The ability to conduct magnetic lines of flux is called permeability, and in a magnetic shield, the degree of permeability is expressed numerically. The standard is free space , which has a permeability value of one. In comparison, MuShield’s magnetic shielding materials range in permeability from 200-350, 000. Knowing the permeability value of the magnetic shielding materials you are choosing from is imperative when selecting the proper materials for your magnetic shield.

• highStandard
• TypeMIL-N-14411

Often times, we receive requests to fabricate magnetic shields to be used at cryogenic temperatures (4.2k). Standard high permeability materials mumetal and HyMu 80 (specs ASTM A753 Alloy Type 4, and MIL-N-14411 Composition 1) are meant to be used at room temperature, so their maximum permeability will degrade and the magnetic shields will saturate as the application reaches cryogenic temperatures. Fortunately, a material called Cryoperm was developed to withstand the extreme cold or cryogenic temperatures.

• SeriesAPI ISO/TS 29001

Westfield Machine, Inc., employs industry best practices to build quality into everything we manufacture, and have specific expertise for producing tight tolerance components for use in oilfield applications. As an API Spec Q1 and API ISOTS 29001 compliant service organization, our quality management systems, which we use to control all operational processes, ensured that we provide consistent results when manufacturing all three of these unique components to guarantee their longevity in an oilfield environment.