DIE CASTING SERVICES
High-Quality Custom & OEM Die Castings
SIMIS is a highly professional Chinese foundry, trusted for delivering end-to-end custom and OEM metal die casting services. We operate from two distinct, adjoining foundry workshops: one specialising in gravity die casting and the other in pressure die casting, giving us the technical flexibility to meet complex demands.
Our extensive die casting capabilities cover aluminium, zinc, copper, and magnesium alloys, utilising both gravity and pressure methods. We proudly supply high-integrity die cast components across many market sectors. SIMIS provides a prestigious, single-source solution. We manage the entire lifecycle from casting and precision machining to heat treatment, surface finishing, and inspection. This allows us to deliver customisable parts and components as fully finished products ready for immediate use.
What is Die Casting?
Die casting is a widely relied upon and highly versatile metal casting process used across global industry for manufacturing precision-engineered components. Fundamentally, it involves forcing or pouring molten non-ferrous alloys—such as aluminium, zinc, or magnesium—into a reusable steel mold, which we term a ‘die’. This method is favored for its ability to produce parts with exceptional dimensional accuracy, high repeatability, and a superior surface finish, frequently minimising the requirement for subsequent machining.
At SIMIS, we employ two distinct techniques: pressure and gravity die casting. Pressure die casting uses hydraulic force to inject the molten metal into the die cavity, whilst gravity casting relies on the natural force of gravity to fill the die. Each process offers unique benefits and is selected based on the specific requirements concerning the component’s material, structure, and application.
Pressure Die Casting Process
Pressure die casting is a highly efficient manufacturing technique used globally for producing intricate, high-precision metal components with excellent surface finishes.
The process starts with die preparation. The two part mold is cleaned, coated with a release lubricant, and clamped shut with high force to withstand injection pressure. Molten metal is injected into the die cavity at high velocity. This force allows the liquid to fill every detail of the mold geometry before it cools and solidifies. Once set, the die opens and ejector pins push the component free.
The part then moves to post-casting treatment, where any excess material is removed and the component is shot blasted, leaving the high-quality, net-shape component ready for further processes like machining, heat treatment, or surface treatment before final inspection.
Gravity Die Casting Process
Gravity die casting, or permanent mold casting, creates dense parts. First, the reusable metal die is cleaned and preheated between 150°C and 300°C. A release coating is applied to control heat and help part removal.
With the die clamped, molten alloy is poured into the sprue cup. The metal flows by its own weight to fill the cavity from the bottom up. This low turbulence fill reduces air entrapment and porosity. The metallic die allows fast cooling, which creates a fine grain structure and high mechanical strength.
Once solidified, the die opens and the part is ejected. The final stage includes trimming to remove excess material and preparing the part for inspection or post processing, such as heat treatments, machining, or surface treatments.
Advantages of Die Casting
Die casting offers a variety of compelling advantages over single-use mould methods like sand casting. These benefits focus on speed, accuracy, and part quality, though the specific advantages often depend on which process is used. Pressure die casting is extremely efficient at high volume production, and parts can be cast with thin walls and complex details; gravity die casting, on the other hand, can produce parts with high structural integrity, exceptional mechanical properties, and better heat treatability; this method can also be used for casting parts with thicker sections.
Superior Surface Finish and Accuracy
Die casting offers two core benefits regarding finish and accuracy. The rigid, precision-machined steel or iron dies ensure very tight tolerances and high repeatability, minimising the need for post-casting machining. Furthermore, the smooth internal surfaces of the metal die yield parts with excellent as-cast finishes, often eliminating the need for expensive secondary finishing operations like polishing or grinding.
High Production Efficiency
Both processes offer high production efficiency; pressure die casting, in particular, provides extremely fast cycle times. It is highly automated and can produce large volumes very quickly (seconds per part), making it cost-effective for mass production and high-volume orders.
Excellent Structural Integrity
The slower, controlled fill of the molten metal in gravity casting reduces air entrapment and turbulence. This produces parts with a denser, lower-porosity microstructure, resulting in superior mechanical properties, strength, and better suitability for subsequent heat treatments.
Reduced Machining Costs
The high precision and superior finish inherent in both pressure and gravity die casting processes deliver a "near-net shape" component. This substantially reduces the requirement for material removal during post-casting procedures, thereby resulting in demonstrably lower machining time and a corresponding reduction in overall production costs for the finished part.
Ability to Cast Complex Features
Both pressure and gravity die casting methods allow for detailed component designs. Pressure die casting can produce parts with extremely thin walls and intricate features. Gravity casting can accommodate thicker sections and complex geometries that require the use of sand cores.
Die Casting Materials
Die casting offers remarkable versatility, handling a comprehensive range of non-ferrous alloys. Our exacting procedures guarantee full adherence to various material specifications, including those from key international organisations such as ASTM, AISI, SAE, BS, DIN, GB, EN, ISO, and JIS. We regularly manufacture high-performance components in aluminium, zinc, magnesium, and copper alloys to support precision engineering across industry sectors. To ensure optimal performance, we operate dedicated facilities, tailoring production precisely to the requirements of each alloy group.
Aluminum Alloy
Aluminium alloy is one of the most commonly used materials for die casting, particularly for high-volume production. It is favored by demanding sectors (automotive, aerospace, electronics) for delivering a superior balance of strength, low weight, and thermal performance.
Zinc Alloy
Zinc alloy is considered the ideal material for the process, especially for small-to-medium, intricate components. Zinc alloy has a low melting point, which provides superior fluidity, and it offers high strength and impact resistance. Common grades are Zamak 2, Zamak 3, and Zamak 5.
Magnesium Alloy
As the lightest structural metal available, magnesium alloy is the component of choice for high-volume die casting in performance-driven sectors (automotive, aerospace, electronics), and common grades include AZ91D, AS41B, and AM60B, providing maximum weight reduction.
Copper Alloy
Copper alloy is an excellent, specialized choice for the process. It offers exceptional electrical conductivity, high strength and hardness, excellent corrosion resistance, dimensional stability and high thermal conductivity. Common grades include C87500, C87800, C92200 and C84400.
Our Advanced Die Casting Capabilities & Expertise
SIMIS moves beyond standard production to solve difficult die casting challenges in three core areas: large components, thin walls, and complex geometries. We use specialized machinery, simulation software, and metallurgical expertise to deliver high-performance parts that conventional foundries cannot achieve. Components produced by our team are used in various applications across industry sectors, and high-end customers use our services for their most demanding projects.
Large Parts Casting
We are fully capable of producing large die castings; with our advanced gravity die casting technique, we can cast parts up to 1.5 meters in length and 40 kg in weight. In most cases, these large parts rely on minimal porosity and high mechanical properties to perform properly.
Thin-Walled Parts Casting
Producing parts with extremely thin walls, often less than 2 millimeters, is a distinct benefit for industries like electric vehicles and electronics, where weight reduction and thermal efficiency are key design goals for peak performance and improved energy efficiency.
Complex Parts Casting
We specialize in casting components with complex internal features, multi-plane partings, and tight tolerances. Our technical capability allows customers to combine several fabricated parts into a single die cast component. This transition reduces assembly time and material costs.
Industries Benefit From Die Casting
We deliver high quality OEM and custom components for a diverse range of industry sectors including automotive, railway, mining and construction machinery, agriculture, engineering and industrial machinery, marine, oil and gas as well as pump and valve. All castings are tested against global quality standards. Speak to our experts to start your projects now. Our team is ready to provide technical support and manufacturing solutions for your specific business needs.
Typical Die Casting Parts
We die cast parts of various shapes, complexities, and alloys. All castings are tested against global quality standards. This level of quality assurance is necessary for parts used in the automotive, fluid handling, railway, and heavy machinery sectors. Speak to our experts to start your die casting projects now. Our team provides technical support and efficient production for your requirements and project goals.
Security Cemera Housing
Mateiral: Aluminum alloy
Application: Consumer electronics
Frame
Mateiral: Zinc alloy
Application: Consumer electronics
Frame Dropout
Mateiral: Aluminum alloy
Application: Bicycle
Side Panel
Mateiral: Magnesium alloy
Application: Motorcycle
Impeller
Mateiral: Aluminum alloy
Application: Power transmission
Pump Gate
Mateiral: Alminum alloy
Application: Industrial machinery
Telecom Enclosure
Mateiral: Aluminum alloy
Application: Telecommunication
Heat Sink
Mateiral: Aluminum alloy
Application: Electronic device
Housing Cover
Mateiral: Copper alloy
Application: Industrial equipment
Housing Bracket
Mateiral: Aluminum alloy
Application: Engineering machinery
Junction Box
Mateiral: Aluninum alloy
Application: Railway
Siphonic Drain Outlet
Mateiral: Aluminum alloy
Application: Construction
Our Advanced Die Casting Equipment & Facilities
To meet market demands, we use hot chamber and cold chamber pressure casting machines with up to 1,250 tons of hydraulic pressure. Our gravity die casting operations use automated tilting machines and manual pouring for large or complex parts. Our workshops also include mesh belt conveyor and hanging shot blasting machines, automated threading machines, and robotic deburring and grinding machines.
Automated Pressure Die Casting Machines
Automated pressure casting machines are integrated systems that perform the entire casting cycle—from metal pouring and injection to part extraction and die spraying—with minimal human intervention.
Combining the core hydraulic press with sophisticated robotics, these machines represent a significant advancement, offering increased production speed, efficiency, and high repeatability for superior quality.
At SIMIS, we are equipped 12 automated pressure die casting machines (both cold and hot chamber), including one with a hydraulic pressure of over 1,250 tons, capable of producing parts up to 650 mm in length and over 20 kgs in weight.
Automated Tilting Machines
Our gravity die casting foundry workshop is equipped with automated tilting machines alongside manual pouring facilities. These machines are specialized equipment where the mold is filled using gravity, rather than high-pressure injection.
Their core feature is the ability to mechanically and programmatically tilt or rotate the die during the pouring process. By controlling the tilt rate, the machine ensures the metal fills the mold cavity smoothly and non-turbulently, minimizing air entrapment and defects.
Our automated tilting machines offer several process benefits, including controlled filling and cooling, rapid adjustments, and high yield. This consistency ultimately improves quality and efficiency while reducing porosity, minimizing cold shuts, and lowering costs.
Robotic Deburring and Grinding Machine
Our robotic deburring and grinding machine is an automated system that uses a multi-axis robotic arm to perform the finishing operations on our cast parts. Instead of a human technician manually holding the part against a fixed grinding wheel or using a hand tool, the computer-controlled robot precisely manipulates the part to clean up edges and surfaces from multiple angles, allowing for comprehensive coverage.
Our robotic deburring system provides benefits such as consistent surface finish, high repeatability, faster cycle times, reduced rework and labour costs, leading to improved quality and efficiency.
Why Choose SIMIS For Die Casting Services?
With a combination of advanced equipment and rich experience, our die casting services offer high-end, fully customizable components. Using our integrated die casting processes, we cast parts in various grades of non-ferrous metal alloys, achieving high efficiency, high performance, smooth surface finishes, and complex geometries. Beyond casting, we have comprehensive in-house capabilities including tool making, machining, surface treatments, and heat treatments, providing customers one-stop services at competitive prices.
Superior Quality
We use strict process control and quality inspection. All parts are 100% inspected (raw and post-casting) at our factory before shipment.
High Precision
We can achieve CT2 tolerance via pressure die casting and CT6 via the gravity casting method.
Casting Simulation
Our advanced casting simulation software optimizes component designs and significantly reduces the risk of defects by accurately modeling the casting process.
One-Stop Solution
Our in-house services, which include tooling design and manufacturing, machining, surface treatments, heat treatment, and assembly, significantly reduce costs for customers.
Competitive Pricing
We provide high-quality, affordably priced castings thanks to our experienced team and advanced, streamlined production capabilities.
High Efficiency
We use advanced automated equipment and process management, offering up to 20% increased efficiency compared to competitors.
Value-Added Services
Our value proposition extends beyond the casting process. Our facilities feature in-house resources including multi-axis CNC machining, heat treatment, surface finishing, assembly, and testing labs. Our comprehensive integration allows total control over quality and lead times, delivering cost-effective, ready-to-use castings.
Die Casting Frequently Asked Questions(FAQs)
What's the lead time of die casting?
The lead time for die casting consists of mainly two cycles: the first is tool making, which takes about 3–6 weeks, depending on the complexity of the part. Following this, the production lead time is typically 2–7 weeks for pressure die casting and 4–8 weeks for gravity die casting. Please note that these are just estimated lead times and can change at different times of the year and are heavily based on the part’s geometry, material required, post-casting requirements, etc. The only way to get an accurate lead time is to consult our expert.
Is die casting prone to defects?
Just like any other metal casting process, die casting can produce parts with defects such as porosity, cold shut, misrun, distortion, cracks, and inclusions. But rest assured, we use advanced process control and casting simulation to minimize defects that can occur. Parts are tested and inspected with all necessary inspection methods, including both destructive testing and NDT. No parts with defects will leave our factory workshop.
What's the difference between pressure die casting and gravity die casting?
Pressure die casting and gravity die casting are two distinct die casting techniques. Pressure die casting uses high-pressure injection, resulting in very fast cycle times (seconds), smooth surface finishes, tight tolerances (CT1–3), and thin walls (1–3 mm). However, these parts generally cannot be heat-treated.
Gravity die casting uses gravity for pouring, resulting in slower cycle times (minutes), good surface finish, and good tolerances (from CT6). Walls are typically thicker (3–5 mm), and parts can feature complex internal geometry through the use of cores, as well as superior strength due to the possibility of heat treatment. In general, pressure die casting incurs a higher tooling cost.
What's the difference between hot chamber and cold chamber die casting?
The main difference lies in how the molten metal is injected, a distinction based on the metal’s melting point. Hot chamber die casting is mainly used for alloys with low melting point, like Zinc, Tin, and Lead. The injection assembly is submerged in the molten metal bath, allowing the metal to be rapidly forced into the die. Because the metal is always staged, this method offers the fastest cycle rates of all die casting techniques.
Conversely, cold chamber die casting is typically used for alloys with high melting point, such as aluminum, brass, and copper, which would corrode a submerged pump. The furnace is separate, and molten metal is ladled into the injection chamber for each shot. This extra step results in slower cycle rates than the hot chamber method.
Which should I choose, die casting or machining from solid?
Both die casting and machining from solid are highly efficient production methods. The choice depends entirely on your project’s complexity, volume, lead time, and budget.
Die casting offers higher production efficiency and a lower unit price, making it ideal for high-volume production. However, it requires a much higher initial investment due to tooling costs. This process (specifically gravity casting) can also produce parts with complex internal features that machining cannot.
Machining from solid is more suitable for low-volume needs and quick lead times because it avoids the lengthy tooling process (only minor fixture costs are typically involved). Use machining for low volume and die casting for high volume.
What's your die casting MOQ?
There is no MOQ (Minimum Order Quantity) for our die cast parts. However, higher volume orders can benefit from a significant discount. For low volumes, the initial tooling cost will make the overall per-unit price higher.
Can other customers use my die casting tooling?
You retain full ownership and intellectual property rights over the tooling; it is reserved exclusively for your orders.
Should I choose die casting or investment casting for aluminum parts?
For casting aluminum parts, both pressure and gravity die casting offer much faster lead times compared to investment casting. Both pressure die casting and gravity die casting have a higher initial tooling cost but a much lower per-unit cost, especially for large quantities. What I would recommend is that you stick to die casting unless the part requires very high tolerances, extremely complex internal structures, and high maximum mechanical strength that the material can achieve.
Die cast aluminum or forged aluminum?
Choosing between die cast aluminum and forged aluminum depends primarily on your needs for volume, cost, strength, and complexity. While both methods can achieve parts with very smooth surfaces, thin walls, and relatively complex shapes, forged aluminum parts have much better mechanical strength and performance and are often used as safety-critical and structural parts in industries like automotive and aerospace.
For parts with complex internal geometry, we recommend you use gravity die casting, as it can also provide moderate mechanical properties. For parts with simpler shapes that require high volume, low unit costs, and where mechanical strength is not a primary concern, pressure die casting is a very good choice. Again, talk to our engineers so we can recommend the optimal process for your specific use case.
Can you recommend a material grade for die cast based on my use case?
Absolutely, we can always discuss the specific scenario where your parts will be used and provide our professional opinion on which material grade to choose, considering several key factors: budget, mechanical strength, application environment, operating temperature, weight, corrosion resistance, conductivity, process (gravity or pressure die casting), machinability, shrinkage, tolerances, and other relevant criteria.. To get a precise material recommendation, you can request a quote and speak to our engineers with the specific mechanical and environmental requirements for your part.
