Hot and cold runner blocks, also known as manifolds, are precision distribution systems used in injection moulding to control the flow of rubber or plastic into mould cavities. They replace traditional runner and gate layouts, delivering material evenly and at controlled temperatures. This reduces waste and improves cycle efficiency.
Hot and cold runner blocks are used to manage and direct material flow into mould cavities under controlled temperature and pressure conditions. By eliminating traditional runners and gates, they reduce waste, improve consistency and shorten cycle times, making them a highly efficient solution for modern moulding systems.
Hot and cold runner blocks are a great solution for:
- High-volume production environments
- Reducing material waste and cost
- Improving flow balance in multi-cavity tools
- Enhancing cycle time efficiency
- Moulding complex or precision components
At Burnsall Engineering, we specialise in the design and manufacture of bespoke hot and cold runner blocks engineered for precise material distribution and thermal control. Every system is designed to match the tool geometry, cavity layout and press requirements, ensuring optimal flow control, consistent quality, and reliable long-term performance in demanding production environments.
We test each runner block rigorously for water-tightness and uniform distribution, supporting high-performance production in both simple and complex multi-cavity moulding applications across a wide range of industries.
A cold pot transfer assembly is a temperature-controlled chamber used in transfer moulding to hold uncured rubber before it’s forced into the mould cavities. Kept below curing temperature, it prevents premature crosslinking, ensuring precise material flow and reducing waste. This controlled system is essential for flashless moulding, where tight control of temperature, venting and alignment is critical.
Cold pot assemblies support flashless transfer moulding by keeping material uncured until it enters the cavity, ensuring a perfect seal and preventing flash formation. This process relies on exceptional control of temperature, venting and cavity geometry to achieve high-integrity, waste-free components.
Cold pot transfer assemblies are a great solution for:
- Flashless rubber moulding applications
- High-precision sealing components
- Rubber-to-metal bonded parts
- Complex geometries requiring tight control
- Reducing post-mould trimming and waste
At Burnsall Engineering, we have extensive experience in designing and manufacturing cold pot transfer assemblies for high-precision and flashless rubber moulding applications. Our capabilities in ultra-fine cavity grinding and precision alignment enable us to achieve the tight tolerances required for true flashless performance.
Each assembly is engineered to maintain strict control of temperature, flow and venting, ensuring consistent results every time. This specialist expertise places us among a small number of UK toolmakers still capable of delivering this level of precision tooling.
Why choose Burnsall?
- 70 years of toolmaking experience
- Fully insured and BS EN ISO 9001 accredited
- In-house team of expert designers and engineers
- State-of-the art modelling and programming applications
- Established relationships with approved contractors
- High quality and competitive lead times
- Awarded the only preferred supply status to a facility in Europe by DuPont Performance Elastomers
