July-August 1998

Galling Protection

Galling is a very common problem experienced by customers using locking helical coil inserts.  Typically galling occurs when the bolt passes through the locking coil and binds.  This is particularly evident with like materials.  The result is that the insert is threaded out of the hole when the bolt is removed, or the insert is threaded deeper into the hole when the bolt is tightened.  Less obvious, is the slight movement of the insert in the hole, which may be undetectable to the operators.

The most common cause of galling is the use of dead soft bolts, e.g., 300 series stainless steel.  CoilThread inserts are made of cold-rolled 304 stainless steel wire (AS7245), work-hardened to a tensile strength above 200,000 psi and a hardness of Rc 43-50.  In order to minimize galling heat-treated screws with a hardness of Rc 36-43 is strongly recommended.  Locking CoilThread® inserts produce torques in accordance to MIL-I-8846 when they are used with heat-treated cadmium plated bolts.  Kato Fastening Systems recommends the use of 300 series stainless bolts be avoided if possible. 

Stainless steel requirements should use A286 aircraft quality screws.  In applications where stainless steel screws are mandatory or when using heat-treated unplated bolts an anti-seize compound, e.g., molybdenum disulfide, must be used in order to minimize galling.

Specifying CoilThread inserts with dry film lubricants or cadmium plating is another option available to the customer.

Customer Contacts

As most of you are already aware, the CoilThread and Hexatorq product lines were recently transferred from Kato Spring of Georgia, Inc. to Kato Fastening Systems, Inc. in Newport News, Virginia. 

In order to familiarize our distributors with our new employees, the following is a list of your key contacts, and their responsibilities:

Aimee Rector – Customer Service Rep.
Primary contact for price and delivery information as well as sales order entry and acknowledgments.

Jeanne Brown – Customer Service Rep.
Primary contact for sales order follow up, Chemical & Physical Reports and Certifications, and all RMA requests.

Vanessa Sczesny – Accounts Receivable
Primary contact for all AR functions.

For all Technical inquiries please contact Rich Davis or Al Qaqish.

KATO Fastening Systems, Inc., 11836 Fishing Point Drive Suite 400, Newport News, VA 23606
Phone: (757) 873-8980, Fax: (757) 873-4920, Web: www.katonet.com