FRP Manhole Cover Making Machinery

Resin composite manhole covers use glass fiber and resin as basic materials, with curing agents, accelerators, etc. as auxiliary materials. A certain amount of pressure is exerted by the FRP manhole cover making machinery and the mold, and forming the resin manhole cover by hot pressing in one step. FRP manhole cover-making machinery is commonly used in four-column structure hydraulic presses such as 315 tons, 400 tons, 500 tons, and 630 tons. The mold uses electric heating, and the heating temperature is mostly 140℃-150℃.

Our FRP manhole cover making machinery consists of a main machine, a hydraulic system, an electrical control system, a pumping station, etc. The main body adopts a three-beam and four-column structure, and the sliding beams are thickened and tempered. It will not deform under high working temperatures. The pressed products are uniform in thickness, strong, and resistant to pressure.

frp manhole cover
FRP manhole cover

The 500-ton FRP manhole cover-making machinery has added two temperature control modules and is equipped with an independent temperature sensor. It supports real-time digital display and manual setting of temperature. The temperatures of the upper and lower molds are generally set at 140℃~150℃. Setting the temperature too low will affect the material flow efficiency and pressure holding time, and may easily cause product defects. Excessive temperature will “scald” the product, causing the manhole cover and the mold to adhere to each other and prevent smooth demoulding.

The 500-ton FRP manhole cover making machinery also has a shutdown and pressure-maintaining function. The industry’s high-quality seals are used, and the cylinder piston rod has been medium-frequency quenched, hard chromium plated, and cylindrically ground. It can maintain pressure for several hours without losing pressure.

The Specific Process Flow of Molded FRP Manhole Covers:

Adding materials (adding the composite resin mixture into the preheated steel mold) → Clamping → Mold filling (the composite resin mixture flows under pressure and fills the entire cavity) → Curing (maintaining a certain value and fully cured at the set pressure and temperature) → Open the mold (take out the composite resin manhole cover).

The 500-ton FRP manhole cover-making machinery adopts a three-stage pressure design of pre-pressing, molding, and pressure maintenance. Pressure is applied in stages according to time and scientifically distributed so that the energy efficiency of the equipment is more significant and the molding pressure is high. The molding quality of composite resin manhole covers is guaranteed. A fully automatic production line for manhole cover has a high degree of automation, a short production cycle, and high production efficiency.

2500T frp manhole cover making machinery
2500T frp manhole cover making machinery

Structural Features of 500-ton FRP Manhole Cover Making Machinery:

  1. The body of the 500-ton composite resin manhole cover molding hydraulic press adopts a three-beam and four-column structure. The upper beam and workbench are combined into a fixed frame through columns, fastening nuts, and adjusting nuts. The accuracy of the frame is adjusted by the adjusting nut, which has good strength, stiffness, and accuracy retention.
  2. After computer optimization design, its strength, rigidity, structure, deformation resistance, etc. all meet the standards and usage requirements. Large parts such as the upper beam, workbench, and slider are steel plate welded parts. Deformation stress is treated through aging vibration.
  3. The body of the FRP manhole cover-making machinery adopts steel plate welding parts, and the four-column guide has high stability. It has good durability and accuracy retention. The working plane has a T-shaped slot for installing molds, which is convenient and quick.
  4. The upper beam is made of steel plate welded parts, with a liquid-filled oil tank on top and a main working oil cylinder inside. Provides power for pressing composite resin manhole covers.
  5. Oil cylinder: It adopts a single-cylinder or multi-cylinder design and is arranged in the upper beam. It is sealed with a high-quality sealing ring. It has good sealing and strong wear resistance. The material of the oil cylinder is No. 45 forging.
  6. There is an ejection device under the working table of the 500-ton FRP manhole cover making machinery. It is mainly used for template ejection, material withdrawal, and other processes.
  7. The material of the column is No. 45 forged steel. The surface of the column is plated with hard chrome to increase wear resistance and hardness.
  8. The nut material of the 500-ton composite resin manhole cover molding hydraulic press is No. 45 forged steel. Match the threads on the column and lock the body.
  9. The limit device is located on the right side of the hydraulic press body. Adjusting the upper and lower limit switches means adjusting the up and down movement position of the slider. The stroke switch controls the upper and lower limit positions.
315T frp manhole cover making machinery

Technical Parameters of FRP Manhole Cover Making Machinery

System pressureMPa25252525
Opening heightmm1200120012001250
Stroke rangemm800800800800
Left and right of the workbenchmm1260120013001500
Before and after the workbenchmm1200120013001300
Lower ejection cylindert63636363
Lower ejection cylinder strokemm300300300300

Zhengxi’s FRP manhole cover making machinery undergoes strict control and inspection one by one from the parts to the equipment leaving the factory. We have strong economic strength, high-end technical equipment, and complete testing methods, and can provide our customers with high-quality composite hydraulic presses of various tonnages. If you have any needs, please contact us immediately.

Related Blogs:

  1. Automatic Production Line for Manhole Cover GRP
  2. Making Composite Manhole Cover

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