There are several different types of PVC pipe fittings used to connect PVC pipes in plumbing and drainage systems:
- Elbows - Allow pipes to be joined at angles
- 90 degree elbows for turning corners, 45 degree elbows for more gradual bends.
- Tees - Allow one pipe to be connected to the side of a straight pipe. Equal tees have same size on all ends, reducing tees connect different pipe sizes.
-Crosses - Allow 4 pipes to intersect at one junction.
- Couplings - Join two pipes in a straight line end-to-end.- Unions - Similar to couplings but can be unscrewed, useful for maintenance.- Caps - Close off the end of a pipe.
- Adapters - Connect pipes of different sizes or threaded ends.
- Bushes - Reduce the size of a pipe opening.
- Plugs - Fit inside and seal pipe ends.- Flanges - Create flanged end connections for bolting to other flanges.- Wyes
- Y-shaped to branch off plumbing lines.
- Traps - U-shaped with inner chamber to prevent backflow.
- Valves - Control flow and manage plumbing systems.The fittings come in different sizes to match the diameters of PVC pipe they will connect. They are molded from PVC material using injection molding or extrusion and machining. The variety of shapes allow extensive plumbing network configurations to be constructed.
There are some key differences between PVC pipe fitting injection molding machines and standard injection molding machines:
- PVC pipe fitting machines are designed specifically for high volume production of small-sized PVC fittings like elbows, tees, unions etc.
- They have a smaller clamping force capacity in the range of 100-300 tons compared to larger 500+ ton standard molding machines.
- The injection unit and screw are also smaller to deliver lower plasticization capacities suited for molding small fittings.
- They use special screws and barrel materials engineered for PVC which can handle the corrosive nature of PVC melt.
- Mold plates are integrated with cooling channels to provide fast cooling for small part sizes.
- Pipe fitting molds are multi-cavity to produce multiple parts in one cycle. 8, 16 or 32 cavity molds are commonly used.
- The molding area is smaller but the molds are very complex to form the intricate fitting shapes.
- Automated parts handling systems are integrated to remove finished fittings post-molding.
- Advanced machines have integrated finishing steps like ejection system, trimmer, deburrer and tapper.
- Overall the machines are optimized for high speed, high volume production of PVC fittings to serve the large plumbing industry demand.So in summary, PVC pipe fitting machines differ in injection molding capacity, mold design and automation features tailored specifically for mass production of small diameter PVC fittings.
