How to specify threaded fasteners

1 min read

Threaded fasteners are still one of the most common mechanical products manufacturing companies require on a daily basis.

In fact, they are so common that accurate terminology is often overlooked in the specification process and the complexity of detail may not be adequately appreciated. Challenge Europe therefore focuses on full conversation with users where they can guide and advise, it states.

“For example, many people are unaware of the simple difference between a bolt and a set screw, a mistake which may cost thousands of pounds in incorrect supply, replacement delays, production delays and the knock-on implications for contractual defaults or even catastrophic service failures, if not corrected before ultimate use in the field,” the company pointed out.

“Consequently, the team at Challenge Europe has developed the experience and skill to guide customers along the path of selecting the right product for the job and helping them to understand the correct terminology to be used at the design stage or when ordering for manufacture.”

Knowing the traps that can be easily fallen into, simple questions are asked that will enable Challenge to determine what it is that the customer is looking for, it added. It is important that even basic information is determined correctly, like how is the customer measuring the length of a product, as well as do they realise that most male fasteners are measured from under the head, whereas countersunk fasteners are measured inclusive of the head? In very basic terms, the company suggests several things to be kept in mind when ordering fasteners:

  • Material – brass, steel, stainless steel etc.
  • Grade – 4.8, 8.8, 10.9, 12.9 etc.
  • Finish – self-colour, zinc plated, chemi-blacked, nickel plated etc.
  • Diameter – metric or imperial
  • Thread form – metric coarse, metric fine, BSW, UNC, UNF, BA, etc.
  • Head form – Hexagon, Countersunk, Pan, Cheese, Cap, etc.
  • Drive form – Socket, Multi-Lobed, Pozi, Phillips, Slotted, etc.
  • Application – how is the fastener being used

There are, of course, many other factors that need to be taken into consideration at the more specialised end of the fastener range, but Challenge Europe believes it can provide technical expertise in helping to prevent the sort of frustration and product failures possible from simple mistakes of the kind described.