SJ Machinery

One-Step Service For Casting And Machining Solution – Since 2003 !

Casting Services

Provide most cost competitive and quality priority casting parts solution to our customer and to maximise our positive impact on casting and CNC machining technology revolution.

Sand Casting

Green sand casting (uses moist sand), dry sand casting (dried sand mold), and resin-bonded sand casting (uses synthetic resins for higher precision).

Investment Casting (Lost-Wax Casting)

Ideal for complex, high-detail parts.Produces parts with tight tolerances and smooth surfaces, suitable for intricate geometries

Die Casting

Semi-Solid Die Casting (Thixocasting), Hot-chamber die casting (for low-melting-point metals like zinc) and cold-chamber die casting (for higher-melting-point metals like aluminum).

Centrifugal Casting

The mold is rotated at high speed while molten metal is poured into it; the force pushes the metal against the mold wall, creating a dense, uniform casting.

Gravity Die Casting

Molten metal fills the mold cavity solely by gravity (no external pressure). It balances cost and precision, suitable for parts with moderate complexity.

Vacuum Casting

Uses a vacuum to remove air from the mold cavity to minimize porosity and ensure complete filling of complex cavities. Commonly used for high-integrity parts in aerospace or medical industries.

About Suijin Machinery

Ningbo Suijin Machinery Technology Co., Ltd is located in Ningbo city, Zhejiang Province.

We are specialized in manufacturing wide range of investment castings and machining parts. The part including various materials such as carbon steel, alloy steel, and stainless steel and so on.

We understand that different industries have varying requirements for casting performance, materials, and structures. Therefore, we have established a comprehensive customization system, from needs analysis to finished product delivery. Whether it’s high-temperature alloy parts for aerospace, high-precision implants for medical devices, or complex structural components for industrial machinery, we can design a customized casting solution based on customer drawings, performance parameters, and even conceptual ideas. From wax pattern formulation adjustment and shell material selection to pouring process optimization, we ensure that each product is precisely tailored to the customer’s specific needs.

Employees

Years in Business

Casting Process

CORE ADVANTAGE

There list the core advantage of our comtapy in the market. 

%

100% control in parts quality

Our company has 100% control in thread checking, leakage test, high requirement tolerance checking with air gauge or position gauge, corrosion resistant for the related material and so on.

R

01

Performance in customer communication, after-sales service and customer
satisfaction, including customized services and rapid response capabilities.

R

02

Capabilities in product research and development, process improvement and
technological innovation, including the speed of new product development.

R

03

Has Strength in quality management and quality control, including the standards
followed, quality assurance system and product quality stability.

R

04

Has advantages in production equipment, technology and human resources,
including production efficiency, capacity and flexibility.

News

Learn more about suijin and castings

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