& Joining Methods
Every joining technique has
particular design requirements, while certain
joint requirements may suggest a particular
joining technique. Design for assembly,
automation, and fastener selection impose
their own requirements.
Bolting is a common fastening
method, for example, but welding may reduce
the weight of an assembly. Naturally, joints
designed for the two techniques would differ
greatly. However, all joint designs must
consider characteristics such as load conditions,
assembly efficiency, operating environment,
overhaul and maintenance, and the materials
Welding is often a cost-effective
way to fabricate. It does not require overlapping
materials, so it eliminates excess weight
caused by other fastening means. Fasteners
do not have to be bought and kept in inventory.
Welding also can reduce costs associated
with extra elements, such as angles fastened
Welded joints distribute
operating stresses evenly. However, design
of a welded joint significantly affects
the welding processes that are used. Many
design options permit excellent welding
performance. Nevertheless, designers who
are unaware of the range of technology and
methods available may fail to realize welding's
There are a variety of
joining methods that do no use fasteners.
Alternative methods are especially important
for some materials.
Methods to join materials
without the use of fasteners include adhesives,
welding, brazing, soldering, clinching,
and injected-metal assembly. In addition,
materials such as plastics, composites,
and metal-ceramic combinations may indicate
the use of certain joining methods.