注塑机冷却塔Water PumpHead可通过分项计算+预留安全余量的方式确定，核心公式为：总Head =（静Head + 系统总阻力 + Water Distributor工作Pressure）× 1.1~1.15，以下是具体确定方法：
? 核心Head组成分项计算
静Head（几何高差）
测量冷却塔集水池最低水位到Water Distributor出口的垂直高度，若冷却塔与Water Pump在同一地面平面，该值通常为2~5m；若冷却塔安装在屋顶、Water Pump在地面，需按实际垂直高差计入。
注塑机设备阻力
注塑机的冷却水路、模具热流道等换热部件的水压降，常规机型阻力为5~8mH₂O，可直接查阅注塑机厂家提供的技术样本获取精准数值。
管路系统总阻力
- 沿程阻力：DN100~DN300管径的循环水管路，每100米管长沿程损失约5~6mH₂O，按实际总供回水管长折算。
- 局部阻力：弯头、阀门、过滤器等管件的阻力，按沿程阻力的30%~50%估算，常规工况下可直接取3~5mH₂O简化计算。
- 冷却塔Water Distributor工作Pressure
注塑机配套的常规逆流式冷却塔，Water Distributor/喷嘴正常工作所需Pressure为5~10mH₂O，具体以冷却塔厂家的参数说明为准。
✅ 最终选型与校验
将以上4部分数值求和后，乘以10%~15%的安全余量，应对管路结垢、滤网堵塞等系统老化带来的额外阻力。常规中小型注塑车间的冷却系统，Water PumpHead通常选15~25m即可满足需求；若冷却Tower Height位安装、管路总长超过200米，需重新核算后适当提升Head。
Head选型需避免两个极端：Head过高会导致Water Pump长期在非高效区运行，浪费电能；Head不足则会使实际循环水量达不到设计值，直接影响注塑机的模具冷却效率，导致制品出现周期变长、变形等问题。
Written by: Zhongliang Yiji Technical Department · 15 Years of Cooling Tower Selection Experience | Last Updated：2026-10-17
FAQ
How to choose between a closed-circuit and an open cooling tower?
For working conditions that demand clean water (such as vacuum furnaces, high-frequency furnaces, and injection machine hydraulic oil cooling), a closed-circuit tower is preferred: the cooled medium circulates inside the coil without direct contact with air, so it resists scaling, algae and particle contamination, with stable heat transfer and low maintenance. For ordinary recirculating water scenarios with tight water budgets or cost sensitivity, an open tower costs less upfront but requires supporting water treatment.
What are the footprint and connections of a 100 t closed-circuit cooling tower?
Taking a standard 100 m3/h closed-circuit tower as an example: overall dimensions are approximately 3500 x 1500 x 2800 mm with a footprint of about 5.25 m2; inlet and outlet piping is typically DN100, with a 5-10 C temperature drop under standard conditions. Refer to the product specification table for details; non-standard dimensions can be customised on site.
How do I size the pump and head for a cooling tower?
Pump flow is selected according to the rated circulating water volume of the cooling tower; head must account for pipeline friction losses, local resistance, equipment elevation difference and the necessary margin. Pressure-bearing equipment such as injection machines also requires reserve for the working pressure. It is recommended to hand the operating data (flow, temperature difference, installation height, pipe diameter and length) to technical staff for calculation, to avoid an undersized pump or excessive head that wastes energy.
What water treatment does a closed-circuit cooling tower need?
The outer circulating water of a closed-circuit tower still contacts air, so softened make-up water, periodic corrosion and scale inhibitor dosing, and control of the concentration ratio are recommended. The inner circulating medium should be softened water, antifreeze or pure water according to process requirements; outdoor installation in winter requires freeze protection (electric tracing or draining).
