Wrong Installation Step, 30% Higher Energy Consumption: Scientific Installation Guide For COLOWE Co Rotating Twin-screw Extruder

Introduction: Why may your cost-effective extruder be running with problems?

In 2024, the revised EU Packaging and Packaging Waste Regulations will officially come into effect, mandating that the proportion of recycled materials in plastic packaging should not be less than 30%; China's "14th Five Year Plan" for circular economy has also raised the target for plastic waste recycling rate to 60%. The global plastic processing industry is undergoing a paradigm shift from "linear consumption" to "closed-loop production". For international customers who are trying recycled materials, biobased materials, or high filling new materials for the first time, choosing a co rotating twin-screw extruder is just the first step - the real challenge is how to ensure stable output of this cost-effective plastic extruder under complex formulation conditions through standardized installation, rather than becoming an energy consumption black hole and a shutdown nightmare.

According to the White Paper on the Full Life Cycle Cost of Extrusion Equipment released by the International Plastics Industry Federation (IPIF) in 2023, equipment hidden losses caused by improper installation can account for 18% to 32% of its total energy consumption, and 75% of early bearing failures and increased screw wear are directly related to foundation levelness and alignment accuracy. In other words, the procurement costs you save may be quietly being swallowed up by incorrect installations.

1, Installation accuracy: the "first principle" of long-term return for cost-effective extruders
1.1 Installation misconceptions and hidden costs of co rotating twin-screw extruders

Most customers who are new to co rotating twin-screw extruders believe that production can be achieved by placing the equipment in place and connecting the water and electricity. But the fact is: a plastic extruder that has not been precisely leveled will experience micrometer level deflection between its cylinder and screw under the action of its own weight and torque, resulting in a significant increase in local contact stress between the screw edge and the inner wall of the cylinder. According to the IPIF white paper data, when the horizontal deviation exceeds 0.05mm/m, the wear rate of the screw and cylinder increases by 2.3 times, and the annual maintenance cost increases by about 18000 yuan (taking the 75 type co rotating twin-screw extruder as an example). Even more covertly, the additional frictional heat caused by deviation can interfere with the temperature control system, causing fluctuations in the melt temperature of ± 7 ℃, directly leading to degradation of recycled materials and an increase in black spots - an unacceptable quality risk for international customers who pursue environmental protection and high cost-effectiveness.

1.2 New requirements for the installation of plastic extruders under the 2024 circular economy policy

Current situation background: Starting from January 2024, the UK plastic packaging tax rate will be raised to £ 217.85 per ton; France imposes punitive tariffs on packaging that does not use 30% recycled materials. This means that the proportion of recycled material processed by the co rotating twin-screw extruder will significantly increase, and the impurities, moisture, and melt index fluctuations in the recycled material will be much higher than those in the new material. If the negative pressure redundancy of the vacuum exhaust system is not reserved during installation (recommended ≥ -0.095MPa) or the concentricity between the side feeder and the main engine is not calibrated, high filling and high impurity formulas are prone to material leakage and bridging at the exhaust port. Authoritative reference: ISO 12100:2010 Mechanical Safety Standard and the European Commission's 2023 Plastic Circular Economy Roadmap both emphasize that interface compatibility and safety protection levels during equipment installation should be adapted in advance to process windows with higher proportions of recycled materials.

2, Three major preparations before installation: avoiding 90% of debugging problems
2.1 Foundation and Levelness: Data speaks for itself

The COLOWE co rotating twin-screw extruder requires a foundation bearing capacity of ≥ 15 tons/square meter, and uses secondary grouting method to fix the foundation bolts. Key control points: Use an electronic level with an accuracy of 0.02mm/m to take 6 measurement points on the front and rear flanges of the cylinder and the output shaft end face of the gearbox. The maximum horizontal deviation must be ≤ 0.03mm/m. Actual test case: A Southeast Asian customer experienced a horizontal deviation of 0.12mm/m due to foundation settlement. After starting up, the screw produced periodic abnormal noise every rotation. Within 3 months, the wear of the cylinder liner reached 0.4mm (normal value ≤ 0.1mm/year), and the customer was forced to shut down for replacement.

2.2 Power supply and grounding: Electrical safety redundancy of co rotating twin-screw extruders

High cost performance extruders do not necessarily equate to "low-end electrical equipment". Kelongwell requires the main motor to have a voltage fluctuation of ≤ ± 5% and to be equipped with an independent grounding electrode (grounding resistance ≤ 4 Ω). Special attention: The frequency converter and heater of the co rotating twin-screw extruder need to be powered separately to avoid high-frequency harmonic interference with the temperature control meter. If there is frequent flicker in the on-site power grid, it is recommended to install input reactors - this can reduce about 15% of motor harmonic heating and extend insulation life by 2-3 years.

2.3 Material Pipeline and Auxiliary Machine Connection: System Thinking for High Cost Effective Plastic Extruders

First time customers often overlook the accuracy of auxiliary machine docking. Kelongwell suggests that the vertical coaxiality between the discharge port of the weight loss feeder and the feeding port of the main machine should be ≤ 1mm, and the length of the flexible connection should not exceed 150mm. The vacuum exhaust pipe should not have a horizontal section, with a slope of ≥ 15 °, to prevent condensate reflux and contamination of the melt. For the water ring pelletizing system that is compatible with plastic extruders, the feed pressure of the pelletizer needs to be calibrated to 0.2~0.25MPa during installation, otherwise it is easy to produce continuous particles and tail materials when cutting recycled materials.

3, Core installation steps: professional specifications from screw combination to cylinder alignment
3.1 Installation sequence and torque control of screw components

The screw combination of the co rotating twin-screw extruder directly affects the dispersion and mixing effect. It is strictly prohibited to use a hammer to strike during installation, and specialized hydraulic disassembly tools must be used. Key torque value: The locking torque of the threaded sleeve is the diameter of the screw core shaft (mm) × 8 N · m, for example, for a 50mm diameter core shaft, the torque is 400N · m. After assembly, it is necessary to use a feeler gauge to check the gap between adjacent kneading blocks. The normal value is 0.3~0.5mm. If the gap is greater than 0.8mm, it indicates that the spline is worn or not locked, and axial movement may occur during operation, causing scratches on the cylinder.

3.2 Connection points of cylinder heating and cooling system

The COLOWE plastic extruder adopts a cast copper heater and soft water circulation cooling. Attention during installation: The mating surface between the heater and the cylinder body must be coated with thermal grease, and the tightening bolts must be tightened diagonally in three times. Otherwise, local overheating will cause thermal deformation of the cylinder body, resulting in screw jamming. After the installation of the cooling water pipeline, it is necessary to maintain a pressure of 1.2 times the working pressure (about 0.6MPa) for 30 minutes without leakage, and confirm that the inlet and outlet directions of each section of the cylinder are consistent with the process requirements.

3.3 Coupling alignment and coaxiality calibration

A diaphragm coupling is used between the output shaft of the gearbox and the screw core shaft. Key installation indicators: radial offset ≤ 0.05mm, angular offset ≤ 0.1 °. Use a laser alignment instrument to measure at four positions: 0 °, 90 °, 180 °, and 270 °. If the deviation is exceeded, it will generate twice the frequency vibration during operation, accelerating gear pitting corrosion and bearing fatigue in the gearbox. Authoritative data shows that for every 0.05mm increase in coaxiality deviation, the lifespan of the gearbox is shortened by about 40%.

4, Quick Q&A on Key Issues (FAQ)
Q1: How to make the foundation embedded parts when first encountering a co rotating twin-screw extruder?
A: The thickness of the pre embedded steel plate should be ≥ 20mm, and the size should be 100mm wider than each side of the equipment base. The specification of the anchor bolt is M24 × 300 (taking 65 type as an example), and the pre embedded depth should be ≥ 250mm. The thickness of the secondary grouting layer should be 50-80mm. The compressive strength of the grouting material should be ≥ C40, and the level can only be adjusted after 7 days of curing.

Q2: How to determine whether the screw clearance of the cost-effective extruder is qualified during installation?
A: After pushing the screw into the cylinder, use a feeler gauge to measure the gap between the screw edge and the cylinder wall at the feeding port, exhaust port, and vacuum port of the cylinder. Standard value: 0.1% to 0.15% of the screw diameter, for example, for a 50mm diameter screw with a gap of 0.05~0.075mm. If the gap is greater than 0.15%, it indicates severe wear on the cylinder or screw and should be replaced before installation, otherwise production will decrease and energy consumption will increase.

Q3: What are the environmental compliance checks that must be completed before debugging?
A: ① Check whether the vacuum exhaust port is connected to the exhaust treatment device (activated carbon or catalytic combustion), and the emission concentration should be lower than the local VOCs standard (such as ≤ 60mg/m ³ in China); ② The cooling water circulation system shall not be directly discharged and shall be equipped with a closed cooling tower; ③ Noise protection: The noise level at a distance of 1 meter around the host should be ≤ 85dB (A). If it exceeds the standard, a soundproof cover should be installed. COLOWE has pre installed safety interlock switches that comply with CE/UL certification before leaving the factory. Customers only need to confirm on site that the effective stroke of the emergency stop button is ≤ 0.5mm.

5, Conclusion: Installation is investment, COLOWE's long termism

For international customers who pursue environmental protection, high cost-effectiveness, and are trying new materials for the first time, the installation of the COLOWE co rotating twin-screw extruder should not be seen as "equipment in place", but rather as an initial investment in the process system. A standardized installation can save 150000 to 200000 yuan in maintenance costs and reduce order losses caused by downtime for your cost-effective plastic extruder within 5 years. As global policies on recycled materials continue to tighten and every gram of energy consumption is included in the carbon footprint, remember: every detail of your installation is casting the strongest foundation for sustainable production.