Total Quality Assurance Program

Palletized raw materials are received in shipping container loads.

The purchase order, which specifies the drawing number, is matched with the shipping documentation.

Raw materials are subjected to a comprehensive testing protocol prior to being accepted into production.

Sampling

• 20 to 40 parts are sampled from each vendor receipt.
• The samples are collected randomly from various cartons within each shipment.

Dimensional acceptance

• Hex head, length, inside shaft diameter, outside shaft diameter are verified to the drawing.

Drill time acceptance

• Fasteners are tested for acceptable drill penetration time.
• Each fastener type is driven at a specific RPM, applied a specific pressure, into a specific gauge of cladding or structural steel.

Ductility acceptance

• A fixed fastener is bent to a five degree angle to determine if the fastener has become excessively brittle during case hardening. The fastener should retain enough ductility to maintain tension and torsional strength without breaking. This test also identifies conditions such as “piping” and hydrogen embrittlement.

Torsion acceptance

• A fixed fastener is twisted at a specific torque to determine that the proper hardness of the fastener is within specified parameters.

Plating/coating acceptance

• If applicable, the fastener is X-rayed to determine the plating or coating thickness is within the specified minimum/maximum.

Fasteners are subjected to a comprehensive testing protocol during manufacturing to insure that processes are rendering specification compliant parts.

Sampling

• Parts are drawn from the various production processes throughout the day.

• Application acceptance Drill time and paint/powder adhesion.

• Paint/powder acceptance Paint/powder thickness and adhesion (MEK rub)

• Paint/powder thickness (socket fit)

• Box count acceptance Filled boxes are sampled and weighed to insure accuracy of count.

• Acceptance tests recording All test results are logged, initialed by the QC tech, and stored via digital image files within the technical services system.

All ST Fastening Systems fasteners are tested in the Technical Services laboratory to establish published structural values.

• Pull-out – the amount of force required to pull a threaded engaged fastener from the material to which it is installed.
• Pull-over – the amount of force required to pull a cladding panel over the head of a fastener/washer assembly.
• Shear – the amount of force required for opposing structural members to shear (cut or break) the fastener.

DILLON 12 TON DYNAMOMETER LOAD CELL, PULL FIXTURE AND CROSS HEAD

All ST Fastening Systems fasteners are tested in the technical services laboratory to establish published environmental and corrosion resistance properties.

• Acid Rain – Kesternich Cabinet accelerates the cyclical effects of acid rain.

KESTERNICH CABINET

• Sodium corrosion – The salt-spray chamber accelerates the cyclical effects of coastal environments.

SALT SPRAY CHAMBER

ST Fastening Systems maintains an ongoing process of improving existing products and developing innovative new products. The Technical Services laboratory provides a means to test virtually every physical characteristic and application performance of any fastener.

The equipment

Buehler Abrasive Water Saw

• Allows the engineer to cut cross sections of fasteners to examine signs of piping, die casting voids, and internal structural defects.

J & L COMPARATOR

• Allows for highly magnified measuring and comparisons of very small dimensions and angles.

MITUTOYO HARDNESS TESTING MACHINE

• Tests the hardness of various metals. It allows the technical staff to verify that test plates (used for drill-time testing) are of the proper hardness. It is also used to verify the internal hardness of case-hardened fasteners

DRILL TESTING MACHINE

• Allows the technical staff to experiment with different geometries for drill-points and pierce-points to determine the most effective design for each application.

FISCHER XDL 240 X-RAY MACHINE

• Allows the technical staff to measure the composition of fastener alloys and how different alloys perform in different applications. It also allows the staff to precisely measure the plating thickness at various points on the fastener, ultimately deriving the optimum plating thickness for performance and environmental durability.