The production of SMC road manhole covers involves several key steps, all of which rely on the use of the SMC road manhole cover mold. Here is an overview of the process:
Material Preparation: The first step in creating SMC road manhole covers is preparing the sheet molding compound (SMC). This compound consists of resin, glass fibers, fillers, and additives that provide the necessary strength and durability. The materials are mixed thoroughly and prepared for molding.
Mold Preparation: The mold is prepped by cleaning it and applying a release agent to ensure that the manhole cover can be easily removed after the molding process. The mold is often designed with detailed features, such as surface patterns for anti-slip purposes or drainage grooves to prevent water accumulation.
Molding Process: The prepared SMC material is placed into the mold. The mold is then closed, and the material is subjected to heat and pressure. The heat causes the SMC to cure and harden, while the pressure ensures that the material fills the mold completely, taking on its shape.
Cooling and Ejection: Once the SMC material has cured, the mold is cooled to allow the manhole cover to solidify further. After sufficient cooling, the mold is opened, and the manhole cover is removed. The cover is inspected for any defects or imperfections, and any excess material (known as flash) is trimmed off.
Quality Control and Finishing: After the manhole cover is ejected from the mold, it undergoes a thorough quality control check. This includes visual inspections, stress tests, and checks for any defects in the material. The final product is then finished with anti-corrosion coatings or surface treatments if needed.
Cover Shape
Round / Rectangle / Square
Cover Load
A15, B125, C250, D400; according to customer standards requirement
Mould Type
Compression mould
Mould Steel
P20 / S50C / S45
Mould Cavity
Single cavity / Multiple cavities / Multiple cavities with interchangeable inserts
Heating System
Oil heating / Electrical rods heating
Ejection System
Hydraulic eject with air assist / hydraulic pins