Limitations of bolted joins:
- Slow and fiddly
- Requires torque tensioning for critical joins
- Requires bolts, nuts or locking nuts, and washers or locking washers
- Point loading stresses
- Cannot be used with brittle materials
- Bolts and nuts relatively slow to make and can only be made out of a limited range of materials
- Requires relatively thick bolting flange
Limitations of clipped joins:
- Chiefly used because it is fast to join and suited to mass production, particularly of consumer electronic or electrical products and toys
- Materials selection is limited to flexible materials such as thermoplastics
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Suited to short lifespan parts with designed obsolescence
- Clip-type seals are cheaper to make but only have a limited number of open and close cycles
- When used for pail lids the size is limited because of the forces required to open and close seals
Limitations of glue joins:
- Chemical incompatibility between materials
- Required bond strength sometimes takes some time to achieve
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Bond can weaken or fail over time or in different environment
- Can not be easily reversed once bonded
- Volatile Organic Compounds and off-gases can be a health/environmental hazard
- Bond is sometimes rapid. Precise alignment often difficult to achieve
- Preparation can be vital
Limitations of riveted joints
- Time consuming
- Material wastage on some types of rivets
- Usually restricted to flat sheets or through holes
- Difficult to remove and replace
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Pop rivet shaft can break before parts are drawn together correctly
- Must be made of ductile material (metals)
- Subject to shear stress during part flexing
- Limited control over joint tension
- Point loading stress where rivets are used
- Can crack brittle materials such as perspex as rivets expand
Limitations of threaded joints
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Over-tightening can cause jumped or stripped thread joint failure
- Large and expensive spanners and tension wrenches are often needed to tighten threads to the correct torque
- Limited to use on circular parts
- Can undo on driven shafts which rotate in both directions
- Grit and debris problematic, especially for plastic threads
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Radial alignment of parts is difficult to achieve with precision
- Friction is a problem on large parts and limits the maximum thread diameter
- Multistart threads are difficult to make and engage
- Not suitable for soft, compressible or elastic materials (ie rubber)
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Threads more difficult to machine or mould
Limitations of clamped joints
- Slower to fit
- Need more access around clamp for fitting
- Requires correct tensioning
- Suitable for limited materials
Limitations of crimped joints
- Used to join metal to incompatible materials, like ceramic or insulated plastic
- Joints not designed to be serviced. Non serviceable assembles are discarded.
Limitations of pressed joints
- Requires a press and specialized jigs
- One-use joint. Generally not reversible
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Compact joint with minimal visual impact
- Good for only some types of materials that are not prone to crack or relax over time
- Good for permanent non-reversible factory-made joints in flexible or ductile materials
- Usually not suitable for gas-tight joints
Limitations of screwed joints
- Screw must be carefully tensioned to avoid stripping thread
- Self tapping screw joints can be used limited times as the part threads wear out
- Requires multiple screws
- Time-consuming and fiddly
- Point loads can lead to joint or seal failure under load
Limitations of welded joints
- Requires specialist equipment and skills
- Heat affected distortion of materials is always difficult to maintain required tolerances
- Burring on inside of pipe or vessel can be problematic
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Slower and more difficult to apply in the field
- Tricky to automate for odd-shaped parts
- Cannot be easily taken apart
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Soldered joints make replacement difficult