Gearbox Housing Casting | K-Series Helical Bevel Reducer Housing

A gear reduced housing, also known as a gear reducer housing or gearbox housing, is a protective enclosure that houses the components of a gear reducer or gearbox. The gear reducer is a mechanical device used to reduce the speed of an input power source (such as an electric motor) while increasing torque. Baoding Guokun is the professional casting factory, who can produce and export various gearbox parts for industrial & mechanical gearbox, such as helical gearbox housing, planetary gearbox housing, worm gearbox housing, bevel gearbox housing, coaxial gearbox frame, spur gearbox housing, and other customized gearbox casings, etc. If you need similar reducer housing, please contact gina@guokuncasting.com to get the quotation or call us 86-18132789710.

Gearbox Castings Tags: Speed reducer castings

Description

Guokun Machinery is a leading metal casting factory in China, specializing in the production of high-precision cast iron gearbox housings and cast steel gearbox bodies for heavy machinery, agricultural equipment, and industrial transmission systems.

Our gearbox housings are manufactured using advanced sand casting, lost foam casting, and shell mould casting processes, ensuring excellent dimensional accuracy, structural integrity, and surface finish. We work with a wide range of materials, including gray cast iron (GG20, GG25), ductile iron (GGG40, GGG50), and alloy cast steel, to meet diverse application requirements.

Key features of our cast gearbox housings:

Custom design & manufacturing based on customer drawings (OEM & ODM services available)
Strict compliance with ISO 9001 and EN 10295 standards
High precision machining (CNC turning, milling, boring) for bearing seats, mounting holes, and oil passages
Heat treatment options: stress relieving, annealing, quenching & tempering
Surface treatment: shot blasting, painting, phosphating, to prevent corrosion
100% inspection on critical dimensions, material composition, and casting quality before delivery

Our cast gearbox housings are widely used in agricultural machinery gearboxes, construction equipment transmissions, industrial gear reducers, and other heavy-duty applications, offering reliable performance under high torque, heavy load, and harsh working conditions.

The component shown is a heavy-duty cast iron gearbox housing for K-series helical-bevel speed reducers, widely applied in industrial transmission equipment, material handling machinery and mixing systems.

Material

We adopt Grey Cast Iron HT250 (GG25 / EN-GJL-250) for this gearbox casing.
HT250 features outstanding vibration absorption, stable mechanical strength, excellent machinability and good thermal conductivity. It effectively supports internal gear sets, bearings and lubrication systems, making it the ideal material for reducer housings under continuous operating loads.

Cast Iron Gearbox Reducer Housing: Durable and commonly used for heavy-duty applications. Mainly produced by sand casting process and lost foam casting process.

A cast iron castings is typically made from gray iron as it is the most common cast iron due to its good castability, machinability, and vibration damping properties, although in situations requiring higher strength and impact resistance, ductile iron might be used instead.

Gray cast iron	ASTM A48 Standard Specification for Gray Iron Castings, for example, ASTM A48 Class 30, ASTM A48M class 35, ASTM A48 class 40, etc.	More brittle but has better vibration damping and is generally cheaper than ductile iron.
Ductile cast iron	ASTM A536 Standard Specification for Ductile Iron Castings. ASTM A536 grade 65-45-12, ASTM A536 Grade 80-55-06, ASTM Gade 60-40-18, etc	Offers greater strength and ductility, making it suitable for applications with higher impact loads.

Gray cast iron is the most common cast iron for helical bevel gearbox housing, helical-bevel gearmotor housing, reducer housing, bevel helical gearbox housing, pump housing, motor housing, gearbox housing, bevel gearbox gray iron housing, etc. Baoding Guokun can offer you the machining process for your customized gearbox housing as per your drawings or design.

Manufacturing Technology: Precoated Sand Casting (Shell Mold Casting)

We produce these gearbox housings via mature precoated sand casting (shell mold casting) technology.

Shell mold casting, also known as precoated sand casting, utilizes resin precoated sand to form thin, rigid shell molds. Heated pattern tools cure precoated sand to create the casting cavity. This process delivers tighter dimensional tolerances and superior surface finish versus green sand casting. It suits complex grey cast iron components like gearbox housings. As a professional foundry, we provide OEM custom metal casting services via mature precoated sand shell mold casting technology.

Shell moulding casting process:

Shell mold casting process
Pattern Creation	A two-piece metal pattern is created in the shape of the desired part, typically from iron or steel. Other materials are sometimes used, such as aluminum for low volume production or graphite for casting reactive materials.
Mold creation	First, each pattern half is heated to 175-370℃(350-7000℉) and coated with a lubricant to facilitate removal. Next, the heated pattern is clamped to a dump box, which contains a mixture of sand and a resin binder. The dump box is inverted, allowing this sand-resin mixture to coat the pattern. The heated pattern partially cures the mixture, which now forms a shell around the pattern. Each pattern half and surrounding shell is cured to completion in an oven and then the shell is ejected from the pattern.
Mold assembly	The two shell halves are joined together and securely clamped to form the complete shell mold. If any cores are required, they are inserted prior to closing the mold. The shell mold is then placed into a flask and supported by a backing material.
Pouring	The mold is securely clamped together while the molten metal is poured from a ladle into the gating system and fills the mold cavity.
Cooling	After the mold has been filled, the molten metal is allowed to cool and solidify into the shape of the final casting.
Casting removal	After the molten metal has cooled, the mold can be broken and the casting removed. Trimming and cleaning processes are required to remove any excess metal from the feed system and any sand from the mold.

Compared with conventional green sand casting, the shell molding process brings remarkable advantages:

Higher dimensional accuracy and consistent casting tolerances
Superior as-cast surface finish with fewer surface defects
Lower machining allowance, saving subsequent CNC processing cost
Great adaptability for complex castings with ribs, cavities and multiple holes

After casting, we conduct riser cutting, shot blasting, stress relief and rough machining as required, delivering high-quality casting blanks ready for finish machining.

Our Custom Casting Service

As a professional metal casting foundry, we focus on OEM customized metal components.
We provide full one-stop solutions including mold design & fabrication, casting production, surface treatment and precision machining.
We can develop custom castings strictly according to customers’ technical drawings or physical samples.
Our product range covers cast iron and cast steel spare parts for reducers, pumps, valves, engineering machinery and hydraulic equipment.