KTM designs and builds custom hot runner injection molds with valve-gate, thermal-gate, and sequential systems — integrated with YUDO, HUSKY, INCOE, Synventive, or Mold-Masters. Every tool ships with DFM, Moldflow, and CMM documentation from our Dongguan facility.
A hot runner injection mold uses a heated manifold and nozzle system to keep polymer molten from the injection machine nozzle all the way to the cavity gate. Unlike a cold runner tool, no sprue or runner is ejected with the part — the material inside the manifold stays melted between cycles. The result: less scrap, shorter cycles, and cleaner gates on finished parts.
A hot runner mold keeps resin molten in a heated manifold and ejects no runner with the part, while a cold runner solidifies a sprue and runner that are ejected with each shot. Hot runners suit high-volume, engineering-resin and Class-A programs; cold runners suit low-volume, prototyping, or frequent material-change work.
| Criterion | Hot Runner | Cold Runner | Best Fit |
|---|---|---|---|
| Material Waste | Near zero | 10–40% runner scrap | Hot runner for engineering resins |
| Cycle Time | Shorter (no runner to cool) | Longer — runner must cool | Hot runner for high-volume |
| Tooling Cost | Higher upfront | Lower upfront | Cold runner for low-volume or prototype |
| Color / Material change | Slower, higher purge volume | Fast and simple | Cold runner for frequent changes |
| Gate Appearance | Clean — no vestige with valve gate | Visible gate mark on part | Hot runner for Class-A surfaces |
| Maintenance Complexity | Higher — heaters, thermocouples, controller | Simple — fewer components | Cold runner for low-tech programs |
Rule of thumb: If your part goes into a consumer-facing product, a medical device, an optical assembly, or a high-cavitation automotive tool, start the conversation assuming hot runner. We'll confirm the ROI against your annual volume and resin cost during the DFM stage.
Still uncertain which system fits your part? Send us your 3D file, Our engineers will return a hot-runner vs cold-runner recommendation with projected runner-scrap savings — within one business day.
Get a Free Hot runner vs Cold runner Feasibility Check →
verified through weight checks at T2/T3 trials
manifold purge protocol included in our process sheet
valve-gate systems leave no visible vestige on Class-A surfaces
Hot runner systems are classified first by gate type — how the melt is delivered into the cavity — and then by how the overall system is configured. Below are the four nozzle types and two advanced configurations we regularly engineer, each selected only after Moldflow confirms fill balance, gate position, and shear rate.
A heated tip delivers melt directly into the cavity without any mechanical valve. Simple structure, cost-effective, and well-suited to commodity resins where a small gate mark is acceptable.
A mechanically actuated pin positively closes the gate between shots — eliminating stringing, drool, and visible gate vestige on finished parts.
A large-bore nozzle feeds resin directly into the cavity with minimal pressure loss. Best for high-volume melt delivery into thick-wall or large geometries.
An ultra-small gate leaves a near-invisible mark and allows clean part separation. Ideal for precision electronic components and high-cavitation small-part tools.
Multiple valve pins open in programmed sequence (t₁ → t₂ → t₃), pushing the melt front across long flow paths and suppressing visible weld lines on large panels.
Multi-cavity balanced manifolds (4/8/16/32), two-level stack molds that double output on a standard press, and family molds that run matched components in one shot.
Not sure which nozzle or system fits your part?
Share your 3D fileOur engineers will recommend the configuration with the best balance of tooling cost, cycle time, and yield.
Send us your 3D file, annual volume, and target resin. You'll receive a technical response from our engineering team within one business day.
From Class-A automotive surfaces to high-cavitation medical consumables, our hot runner tooling is engineered around the specific demands of each industry.
Every industry brings its own failure modes. In our DFM review, we specifically address the defects most relevant to your application — sink marks on automotive Class-A surfaces, weld lines on large sequential-gate parts, and flash on high-cavitation medical tools.
We don't sell hot runner systems — we engineer the mold around the right one. Among the six brands below, YUDO and INCOE are the systems our engineers integrate most often: YUDO for its strong price-to-performance balance, and INCOE for its wide adoption among U.S. customers.
North American customers often standardize on INCOE for its U.S. service network. European customers frequently specify HUSKY, Synventive, or HRSflow. Whatever you specify, we design the mold base, manifold pocket, wiring routing, and cooling to match the OEM spec.
Not sure which brand fits? For cost-sensitive mid-volume programs we typically recommend YUDO; for U.S.-based programs with local service needs, INCOE. The final choice is always based on your volume, resin, and cavity count.
Have a preferred hot runner brand, or want our recommendation based on your region and volume?
Discuss your project with our engineersEvery hot runner mold carries one extra decision that cold runner tools don't: where does the hot runner system come from? We support two procurement paths — and apply the same integration checkpoints to both.
We recommend and procure the system based on your project. For cost-sensitive mid-volume programs we typically specify YUDO; for U.S.-based programs needing local service, INCOE. Other brands supplied on request.
Already purchased a HUSKY, Synventive, Mold-Masters, HRSflow, or other system? Ship it to our Dongguan facility — we'll engineer the mold base, manifold pocket, wiring routing, and cooling to match your OEM specification exactly.
Regardless of who supplies the system, every hot runner mold we build passes the same five integration checks — the ones that keep leakage, stringing, color contamination, and thermal degradation out of your production floor.
Have an OEM hot runner ready to ship, or want us to recommend one?
Start the conversation with an engineerMany of our customers have stayed with us for over a decade. The reasons are consistent — and they have nothing to do with being the cheapest.
Our founder is a tooling engineer with 25 years on the shop floor. Technical questions go straight to someone who can actually answer them.
Quotes include mold base, cavity & core, hot runner system, cooling, texture, and trials. Changes only happen through signed ECNs.
DFM, Moldflow, steel and material certs, CMM report, and mold trial report— delivered in English and matched to European and U.S. quality systems.
Mold → injection (40 presses, 90T–600T, plus a 3300T partner) → secondary processes → turnkey equipment sourcing when needed.
Many customers have been with us 10+ years because risk stays low and communication stays clear — not because we locked them in.
The questions our engineers hear most often before a project kick-off.
Our engineering team is available to answer your specific questions about hot runner mold design, materials, and manufacturing processes etc.
Share your 3D file and part volume — an engineer (not a sales bot) will review it and reply within one business day with a DFM check, gate recommendation, and a clearly scoped quotation.
We're not the cheapest quote on your list — and we tell customers that upfront. What you get instead is engineering clarity, predictable delivery, and a documented build process that matches how EU and U.S. buyers expect tooling to be managed.
Comprehensive design review to optimize manufacturability
Predictive analysis for fill, pack, and warpage
Consistent quality through rigorous process management
Dedicated project support with timely updates
Detailed quotations with no hidden charges
Ongoing maintenance and engineering change support
