Flexible elastomer protects controller in harsh environment
Canadian Plastics
A problem with circuit board failures in DeLaval's automated milking systems was traced to a leaking seal on the control box, so the company began working with Rofshus Precision Machine of Minnesota t...
A problem with circuit board failures in DeLaval’s automated milking systems was traced to a leaking seal on the control box, so the company began working with Rofshus Precision Machine of Minnesota to redesign the unit using a better sealing material.
The control box is sealed with a keypad that must be flexible enough to depress internal push buttons, yet strong and capable of sealing out the elements. DeLaval specified a deep blue color for brand identification. In addition, the material had to be bonded to plastic lenses for indicator lights and printed with highly readable identifiers for the buttons.
“We tried a silicone material which successfully kept out the moisture,” says Cork Stanley, owner of Rofshus, “but color was lacking and the printing rubbed off.”
The final choice for the keypad was a precolored compound from RTP Company. The RTP 2800 Series compound is a 60 Shore A durometer, fatique-resistant olefinic thermoplastic elastomer in DeLaval’s signature reflex blue color. Molded-in holes create a sort of mortise and tenon joint for the lenses, which are insert molded. This process fastens them both mechanically and chemically to the surrounding material.
RTP Company 507-454-6900
