Cup Mould
SINOMOULD is a world‑leading manufacturer of thin‑wall injection moulds, with over 20 years of technical expertise in the field of disposable cup moulds. For the moulding characteristics of food‑grade transparent materials such as PS, PP, and PET, our thin‑wall cup moulds feature a unique separate interlocking precision positioning structure and a conformal high‑efficiency cooling system. Combined with S136 mirror steel and valve‑gated hot runners, they can achieve a high‑transparency, scratch‑free, stable mass production of an 8g PS cup in an ultra‑short cycle time of 3.5 seconds.
SINOMOULD’s beverage cup moulds are renowned for high‑precision dimensional control, no gate residue, and fully automatic air‑assisted demoulding. They are the preferred mould supplier for the milk tea market, airline cups, and the disposable fast‑moving consumer goods packaging industry.
Cup Mould Specifications
The following are the core technical specifications of SINOMOULD’s high‑precision PS thin‑wall cup mould. This mould is structurally optimized for a 200HH high‑speed injection moulding machine and supports a design compatible with both 4‑cavity and 8‑cavity configurations
| Product Dimensions & Specification | 250ml capacity / 8g PS thin‑wall cup | Number of Cavities | 4 cavities or 8 cavities (selectable) |
|---|---|---|---|
| Product Description | Disposable transparent PS cup (8g) | Compatible Injection Machine Tonnage | DKM‑200HH |
| Main Mould Steel | S136 vacuum heat‑treated stainless steel | Injection System | Anole valve‑gated hot runner system |
| Ejection / Demoulding System | High‑pressure air demoulding | Cycle Time | 3.5 seconds |
| Design Life | Over 3 million cycles | Standard Delivery Time | 55 working days |
| Core Features | Separate interlocking precision positioning, high‑efficiency cooling circuits, A1‑grade mirror polishing |
Key Quality Points of Cup Mould
In cup mould manufacturing, the uniformity of wall thickness, retention of transparency, and elimination of flash are the only standards for measuring mould quality. Through the following quality control points, SINOMOULD ensures that every mould is ready for fully automated high‑speed production upon delivery:
- Separate Interlocking Precision Positioning Structure
To address the common pain points of uneven wall thickness and flash in thin‑wall cup moulds, SINOMOULD uses a patented separate conical interlocking precision positioning structure on the moving and stationary halves. At the moment of high‑speed, low‑pressure filling, this structure resists lateral impact from injection pressure, maintaining a consistent single‑side fit clearance between core and cavity of 0.01‑0.02 mm. This ensures extremely uniform wall thickness of the 8g cup and eliminates sticking or flash under high‑speed moulding.
- S136 High‑Gloss Mirror Finish & Food‑Grade Anti‑Corrosion Treatment
As a food‑contact PS cup mould, the cavity and core are strictly processed to A1‑grade mirror polishing standards (Ra ≤ 0.025μm) . After vacuum heat treatment and cryogenic stress relief, the S136 ESR stainless steel achieves a stable hardness around HRC 50, with a surface free of pinholes, orange peel, or polishing marks. This not only ensures high transparency and gloss of the PS cup but also guarantees that the mould will not rust or develop black deposits even after long‑term storage in a humid environment.
- High‑Efficiency Conformal Cooling Water Circuit System
The core and cavity incorporate dense 3D conformal cooling + baffe‑type water wells as a composite water circuit. Using Mouldflow transient cooling analysis to optimize water hole diameter and spacing, we ensure that the cup rim, body, and bottom cool at the same rate and shrink synchronously within the ultra‑short 3.5‑second cycle. The high‑heat‑exchange cooling system effectively suppresses residual stress in the PS melt, resulting in a round cup rim after demoulding and a bottom free from vacuum‑induced deformation.
- Anole Valve Gate System & Gate Mark Control
To meet the high aesthetic requirements of transparent PS cups, we use Anole valve‑gated nozzles. The valve needle action is extremely fast with tight shut‑off, producing a clean gate break with a stable diameter of 1.0‑1.5 mm and no white‑ring halo or stringing. A well‑designed hot runner temperature control profile eliminates stagnation and degradation of the PS melt during 8‑cavity filling, ensuring consistent transparency and color for every cup.
Cup Mould Machining Essentials
A cup mould capable of running a 3.5‑second cycle requires micron‑level precision in its manufacturing process. SINOMOULD’s cup mould machining process focuses on the following key points:
- Jig Grinding (JG) & Precise Grinding of Conical Interlocks
As the foundation of the interlocking structure, the fixing holes for cavity and core inserts, as well as the tapered locking blocks, are machined using high‑precision jig grinding machines. This ensures consistent insert interchangeability among the 4/8 cavities and a tapered surface contact area of over 90% as verified by red‑dye contact testing. Precise tapered fit is the machining foundation for a flash‑free high‑gloss cup mould.
- Integrated High‑Speed Milling & Mirror Polishing Process
The curved surfaces of the cup body are milled with 5‑axis high‑speed machining centers to Ra ≤ 0.4μm, greatly reducing subsequent polishing time. The polishing workshop strictly follows a 12‑step manual polishing process—from coarse stones to diamond paste—tailored to the characteristics of S136 stainless steel. A final microscopic inspection confirms the absence of any fine machining marks, ensuring that the PS melt does not generate shear‑induced heating or scratching during ultra‑fast filling.
- Precision Deep‑Hole Drilling & Micro‑EDM for Air Channels
For air‑assisted demoulding, we use CNC deep‑hole drilling to machine air channels and Micro‑EDM to create venting holes on the core surface. Precise control of hole size and distribution ensures that the compressed air pulses act uniformly on the inner cup surface, gently “lifting” the cup out. This completely replaces ejector pins, eliminating any ejector marks on the cup surface.
Mould Flow Analysis for Cup Mould
Cup Mould Testing Video
SINOMOULD provides professional custom PS/PP/PET thin‑wall cup mould solutions, specializing in multi‑cavity, high‑gloss, ultra‑thin‑wall container mould development. If you need a specific technical proposal and quotation based on your cup weight and production capacity, please feel free to contact our disposable container mould expert team.