PU Foaming Pre Insulated Pipe HDPE Jacket Extrusion Line

Pre-insulated pipe machine,Vacuum Jacketed Pipe Production Line

gas/oil /water pipeline Puf Pre-Insulated Pipe PE shell casing plastic Machinery

The equipment consists of a steel pipe chain conveyor and pipe assembling table. The conveyor continuously passes the steel pipe into the PE jacket on the assembling table.

1. Name: HSD-1220# New type circulating double-chain pipe conveyor and assembling machine.
2. Transmission power: 960r/min 4.0KW.
3. Current: 380V 50HZ three-phase four-wire.
4. Transmission type: cycloid reducer, chain transmission.
5. Lubrication: gear oil, industrial butter.
6. Control: Mechanical
7. Installation requirements: horizontal installation.
8. Appearance size: a total of 4 sections 26x1.3x0.65 (m)
9, can wear Ф219-Ф1220 steel pipe.

Technical Prameters:

HDPE Jacket Process Flow:

1. Vacuum Feeding of PE Granules: The raw PE granules are automatically fed into the system via vacuum suction.At the initial stage of the plastic pipe production process, raw polyethylene (PE) granules are efficiently introduced into the system through a sophisticated vacuum feeding mechanism. This automated process eliminates manual handling, minimizing the risk of contamination and ensuring a continuous, uninterrupted flow of raw material. The vacuum suction creates a powerful force that draws the PE granules from their storage containers, transporting them smoothly and precisely into the next stage of the production line.
2. Hot Air Drying: The granules are dried using hot air to remove moisture, ensuring optimal extrusion quality.To achieve optimal extrusion quality, the PE granules undergo a critical drying step using hot air. A state-of-the-art hot air drying system circulates heated air around the granules, effectively removing moisture and volatile compounds. This meticulous drying process is crucial as moisture can adversely affect the melting behavior and ultimate quality of the extruded plastic. By ensuring that the granules are thoroughly dried, the subsequent extrusion process is optimized, resulting in pipes with superior mechanical properties and dimensional stability.
3. Extrusion Plasticizing: The dried granules are plasticized through the extruder, heated and mixed to form a molten plastic mass.The dried PE granules are then fed into the extruder, where they undergo a rigorous plasticizing process. The extruder, equipped with a rotating screw and heating elements, gradually heats and mixes the granules, transforming them into a viscous, molten plastic mass. This plasticizing phase is highly controlled, ensuring that the temperature and mixing conditions are precisely maintained to achieve a uniform and homogeneous melt. The resulting molten plastic is ready to be shaped into the desired pipe profile.
4. Mold Shaping: The molten plastic is shaped into the desired pipe profile by passing through the extrusion die.The molten plastic is then forced through a precisely engineered extrusion die, which imparts the desired shape and dimensions to the pipe. The extrusion die, acting as a mold, shapes the plastic into a continuous, seamless pipe with a smooth, uniform surface. The high-precision design of the die ensures that the extruded pipe meets strict quality standards and specifications, ready for further processing.
5. Vacuum Sizing: The pipe is then subjected to vacuum sizing, adjusting its dimensions to precise specifications.After extrusion, the pipe enters a vacuum sizing station where its dimensions are adjusted to precise specifications. The vacuum sizing process utilizes the principle of differential pressure to gently pull the pipe into a sizing sleeve, ensuring that its outer and inner diameters are within tight tolerances. This step is crucial for achieving pipes with consistent quality and precise dimensions, which are essential for various applications.
6. Water Cooling: The pipe is cooled rapidly by immersion in a water tank to solidify its shape and structure.To solidify the pipe's shape and structure, it is rapidly cooled by immersion in a water tank. The cold water rapidly extracts heat from the pipe's surface, causing it to solidify quickly and uniformly. This cooling process is carefully controlled to prevent warping, distortion, or other defects. Once cooled, the pipe retains its shape and structural integrity, ready for the next stage of production.
7. Pulling Out: The solidified pipe is pulled out of the cooling tank at a controlled speed.
8. Cutting: The pipe is cut to the desired length using a precision cutting machine.
9. Carrier Laying-off: The cut pipes are then neatly laid off onto a carrier for further handling or packaging

Composition of Equipments:

1. Hopper Dryer
2. Single Screw Extruder
3. Extrusion Mould Die
4. Head Bracket
5. Vacuum Calibration Device
6. Water Cooling Tank
7. Haul-off Unit
8. Planetary Cutting Machine
9. Pipe Bracket
10. Loader
11. PLC (Programmable Logic Controller)

The production steps of the insulation layer for a pre-insulated pipe, specifically focusing on the polyurethane (PU) foam insulation, are outlined below in detail:

1. Formation of the Casing Structure:
   • The steel pipe is first inserted into the high-density polyethylene (HDPE) outer protection pipe, creating a casing structure.
   • Supports are evenly arranged in the annular space between the steel pipe and the HDPE outer pipe to maintain a uniform distance and prevent the two pipes from touching directly.
   • The two ends of the casing are sealed with flanges to ensure that the polyurethane foaming material will be contained within the space during the injection process.
2. Preparation of the Steel Pipe Surface:
   • Prior to the injection of the insulation material, the surface of the steel pipe undergoes pre-treatment such as shot blasting or blast cleaning. This step removes any impurities, rust, or scale, providing a clean and suitable surface for optimal adhesion of the polyurethane insulation.
   • Additionally, corona treatment of the polyethylene pipe shell's surface may also be performed to enhance its adhesion properties.
3. Injection of Polyurethane Foaming Material:
   • The casing structure is hoisted onto a foaming platform specifically designed for this purpose.
   • A high-pressure foaming machine is used to inject the polyurethane foaming material into the casing. The material expands and fills the entire annular space between the steel pipe and the HDPE outer pipe.