Transmission Case & Gearbox Housing Mold – Gravity and Low Pressure Process Matching and Tolerance Control
Transmission case and gearbox housing molds need precise dimensional tolerance control for assembly, Xinfeng Mold classifies process schemes based on product wall thickness and usage scenarios.
Thick-wall gearbox housing parts adopt gravity casting molds with 18–22 cm/s filling speed, improving molding efficiency by 25% compared with low pressure process.
Thin-wall transmission case parts apply low pressure molds with 0.04 MPa constant pressure filling, reducing assembly dimensional deviation to below 0.08 mm.
Mold parting surface flatness of box parts is controlled within 0.02 mm, ensuring 100% fitting rate of subsequent mechanical assembly surfaces.
Box mold steel hardness is stabilized at 41–46 HRC, adapting to 110,000+ cycle mass production of automotive transmission accessories.
Independent slag collection and exhaust structures are set at box rib positions, reducing internal slag inclusion and cold shut defects by 60%.
Mold temperature for box casting production is maintained at 280–330°C, avoiding residual stress deformation of thin rib structures.
Trial production of transmission box molds requires dimension inspection of 30 key assembly holes to ensure 100% tolerance compliance.
Cooling pipeline blockage inspection is required every 2000 cycles to prevent local overheating and rib shrinkage defects.
Most manufacturers blindly use low pressure process for thick box parts, increasing mold cost by 30% without quality improvement.
Gearbox housing mold structural design is similar to motor housing molds, focusing on internal cavity flatness and assembly precision.
Differential pressure process is only suitable for high-end sealed transmission boxes, with ordinary models adopting gravity and low pressure composite schemes.
FAQ
Q1: Which process is suitable for thick-wall gearbox housing? A1: Gravity casting process is preferred for cost and efficiency advantages.
Q2: What is the assembly tolerance standard for transmission case molds? A2: Key hole position deviation is strictly controlled within 0.08 mm.
Q3: What is the production temperature range for box molds? A3: Stable production temperature is 280°C to 330°C.
Q4: How many production cycles can box molds support? A4: Standard molds achieve stable production of 110,000 cycles.
Q5: What is the flatness standard of mold parting surface? A5: Parting surface flatness error shall not exceed 0.02 mm.
Core Embedded Keywords: Transmission Case, Gearbox Housing, Motor Housing, Gravity Casting Mold, Low Pressure Casting Mold, Differential Pressure Mold, Mold Tolerance Control, Automotive Transmission Mold, Casting Defect Control, Mold Production Efficiency