Must for Intake Manifold Design

          Intake Manifold : Design Process

Process Step 1 - 

Firstly the basic design criteria like cost, weight and life will be analyzed. After freezing basic design criteria, design failure mode effect analysis will be done. Intake manifold is a single unit part but there are so many complicated parts which are mounted on it such as throttle diffuser pipe, MAP Sensor, Resonator, Strength Stiffener. For Intake Manifold Assembly on both end gaskets are used to avoid air leakage. As mass of Throttle is less M6 Bolts can be used for tightening , on the other hand intake mounting on cylinder head M8 Bolt will be better because whole intake mass will work like a simply supported beam, which will cause moment in bolt, specially at high vibration, braking deceleration and starting time, so M8 bolts will be safer. (Note: A – Best/Go, B- Mediocre/Compromise, C- Not Suitable/No Go)

Child Part	Requirement	Material	Manufacturing	Cost	Weight	Life	Design Review
Manifold	Burst Pressure 10 Bar, Vibration 30 g, Working Temperature 200 ° C, Surface Roughness Ra8, Ra16 and Ra32	PA66 GF35	Moulding	C	A	B	PA66 GF35 has low weight but moulding tool will be very costly. Also machining (R8) in plastic is very difficult process, only few suppliers can do it by moulding. ADC12 will be used for Pressure die casting and then machining will be done. To save cost Sand Casting can be done for making proto part. By Machining desired surface finish can be archived in ADC 12.
		ADC 12	PDC, Machining	A	B	A
		Steel Alloy	Machining	B	B	A
Gasket	Working Temperature 300 ° C Leakage Pressure 10Bar	Paper	Die Cutting	A	/	C	Circular Rubber Gasket (like O Ring) has better sealing property.  Groove can be made in body of runner plate to mount it on cylinder head. However we will use Paper Gasket as it is easy to design & manufactures and low cost.
		Rubber	Compression Moulding	C	/	A
Insert, Collar for Mounting or Nipple for Inlet/ outlet	Compressive Load 1000 N, Torque 200Nm No Rusting	Aluminum	Casting Heat Treatment Machining	A	C	B	Press fitted brass nipple can be easily assembled in Aluminum Intake Manifold. Separate Brass Collar is not required Aluminum Intake however mounting hole must have high surface finish near Ra16 or Ra 32.
		Brass		C	A	A
		Steel		B	A	A
Fastener	30 G Vibration 100 N Load No Rust	M6 Class8.8	Machining, Heat Treatment, Thread Making	-	-	-	For Restrictor and MAP Sensor M6 will be used. For Manifold assembly on cylinder M8 will be used.
		M6 Class10.9		-	-	-
		M8 Class8.8		-	-	-

Step 2 - It is unavoidable to design manifold without DFMEA. Check next article for Intake Manifold DFMEA ( Design Failure Mode Effect Analysis)