The quality of ship engine parts affects the power output, fuel efficiency and service life of the ship. High-quality parts can reduce the frequency of failures and reduce maintenance costs. QD is a professional ship engine parts casting factory and supplier. We provide customers with high-quality casting solutions.
Common marine engine parts
Moving parts
- Crankshaft: Responsible for converting the reciprocating motion of the piston into rotational motion. Driving the ship forward. High strength and toughness requirements.
- Connecting rod: Connects the piston and the crankshaft. Need to maintain stability during high-speed reciprocating motion. Need to have good wear resistance and fatigue resistance.
Fixed parts
- Cylinder block: The “skeleton” of the engine. It provides operating space for the piston, crankshaft, etc. It also performs functions such as heat dissipation. It needs to have good rigidity and sealing.
- Cylinder head: It covers the top of the cylinder block. It needs to withstand the impact of high-temperature and high-pressure gas. It has strict requirements on heat resistance and sealing.
Fuel system components
- Injector housing: Responsible for fixing the injector and guiding fuel injection. It comes into contact with high-pressure fuel during operation. It must be pressure-resistant and airtight.
- Fuel pump housing: Protects the internal parts of the fuel pump. It must be high-strength and corrosion-resistant.
Intake and exhaust system components
- Intake manifold: Distributes air or mixed gas evenly to each cylinder. Must have good airflow guidance ability and heat resistance.
- Exhaust manifold: Collects exhaust gas from each cylinder and guides it to the exhaust pipe. The working environment temperature is extremely high. Must have excellent high temperature resistance and anti-oxidation performance.
Common casting materials for marine engine parts
| Casting material | Feature | Advantage | Application |
| Gray cast iron | Good castability and machinability. Suitable for mass production | Low cost. Good shock absorption. Good wear resistance | Cylinder block, cylinder head and other fixed parts |
| Ductile Iron | The strength and toughness are close to those of steel. At the same time, the casting advantages of cast iron are retained | Excellent mechanical properties. Strong fatigue resistance. High cost performance | Crankshaft, connecting rod and other moving parts |
| Cast Steel | High strength. Good toughness. Able to withstand complex loads | Wide range of applications. Excellent resistance to high temperatures and corrosion | Exhaust manifolds, large gears, etc. |
| Aluminum Alloy | Low density. Good thermal conductivity. Obvious advantage of lightweight | Reduce the overall weight of the engine. Improve fuel efficiency | Small intake manifold, lightweight accessories |
| Compacted Graphite Iron | It combines the shock absorption of grey cast iron with the strength of ductile iron | Outstanding resistance to thermal fatigue. Suitable for high temperature working environment | Cylinder head, exhaust system key components |
QD Lost Foam Casting Process
QD has been engaged in the field of lost foam casting for more than 20 years and has formed a set of refined process systems that are different from those of ordinary suppliers.
- Mold design: Customize the foam model based on the stress characteristics and temperature environment of the accessories. Ensure the model size and structural accuracy.
- Paint coating stage: Use special high-temperature resistant paint. Improve the coating adhesion through multi-layer coating process. Lay the foundation for the surface quality of castings.
- Casting process: Accurately control the flow speed and temperature of the molten metal. Reduce defects such as pores and shrinkage.
QD integrates dimensional inspection throughout the entire process:
- After pouring, the casting is preliminarily checked for size by 3D scanning. Unqualified products are screened out.
- The key dimensions are measured one by one by precision testing equipment. Ensure that every accessory meets the design standards.
This dual control of “prevention + detection” is in sharp contrast to the mode of ordinary suppliers relying only on final sampling. It effectively reduces the rework rate of subsequent assembly for customers and ensures the reliability of accessories from the source.
QD Surface Treatment Process
In addition to core casting capabilities. QD also provides comprehensive machining and heat treatment value-added services. Forming a one-stop solution of “casting + subsequent processing”.
Machining: Special equipment is used according to the precision requirements of the accessories. The dimensions are refined through precision turning, milling and other processes. Ensure the assembly compatibility of accessories with other parts.
Heat treatment: Customized processes for accessories of different materials. For example, tempering of cast steel accessories is performed to improve strength. Aging treatment of ductile iron accessories is performed to stabilize performance.
QD’s one-stop full-chain service model saves customers the trouble of looking for third-party processing manufacturers. It shortens the production cycle. Ensures the stability of accessory quality through the consistency of process connection.
QD Marine Engine Castings
The lost foam casting crankshaft produced by QD is made of ductile iron. The uniformity of the internal structure is improved by optimizing the casting process. It can withstand the long-term high torque operation of the ship engine.
As a key component for the crankshaft, QD uses the lost foam process to achieve one-step molding of complex structures. This reduces the amount of subsequent processing and takes into account both strength and precision.
QD uses grey cast iron or cast steel to cast the cylinder head. The complex channels are formed in one piece through the lost foam process. It is installed on the top of the cylinder liner and forms the combustion chamber together with the cylinder liner and piston.
The injector is a precision component of the fuel system. QD achieves its precise molding through lost foam casting. The subsequent machining ensures the installation accuracy of the injector.
Cast iron oil pump produced by QD. With the molding advantage of lost foam casting, it can be cast in one step. It is matched with special heat treatment process to improve performance.
Advantages of cooperating with QD
Choosing QD means choosing a partner who can “solve problems, reduce costs, and ensure delivery”
- Reliable quality: Full process control from casting to surface treatment. Ensure that accessories meet working conditions. Reduce the risk of failure.
- More efficient: One-stop service. Eliminate intermediate links. Shorten delivery cycle. Make project progress smoother.
- Cost optimization: Reduce scrap rate through process optimization. Combined with large-scale production. Achieve high cost performance. Help customers control procurement costs.
QD also provides professional after-sales support. Provide technical answers to problems encountered in the use of accessories. Make the cooperation worry-free throughout the process.
Choosing QD means choosing high-quality marine engine parts, and choosing a reliable long-term cooperation guarantee.