Engineered to your process — not configured from a catalog. Denver-built since 1968.
Deltech designs and builds custom high-temperature furnaces to 2000 °C for processes no catalog furnace fits. Around 90% of what leaves our Denver shop is custom in some way — engineered around a customer’s material, temperature, atmosphere and throughput rather than selected from a model number. We have been doing it since 1968.
Start with the process, not the furnace
Most people who need a custom furnace do not arrive knowing which furnace they need. They arrive with a process. They are electrifying a gas-fired kiln and need the same thermal profile without combustion. They are scaling a calcination step from the bench to production. They are processing high purity powders that need specific temperature and retention times. They need to anneal glass tube stock horizontally, or melt a glass whose chemistry rules out a vacuum. None of those are a model number, and none of them are answered by a specification table.
That is the conversation we are built for. Tell us what the material is, what temperature and atmosphere it has to see, how it has to move through the hot zone and what you need to measure, and we will tell you whether it is a standard furnace, a modified standard, or a system that has to be engineered from the process out. Sometimes the answer is that a catalog furnace already does the job — and we will say so.
How a custom furnace gets built
A capital furnace purchase is not a transaction, and nobody should be asked to approve one without knowing what happens between the purchase order and a working furnace on their floor. This is the sequence.
Step 1: Engineering inquiry
A conversation with an engineer, not a form response. We work through the process: material and charge, peak and soak temperatures, ramp requirements, atmosphere, loading method, cycle time, throughput, available utilities and the physical space. We will address the custom needs of your build and provide a recommendation for the ideal furnace for your application. Most of what determines the design is settled here.
Step 2: Specification and budgetary proposal
A written specification of what we propose to build, with estimated lead times and a budgetary figure attached. We can often turn this around in as little as 24 hours. It is written to stand on its own, so it can go straight into a grant application or a capital request without us there to explain it.
Step 3: Design and engineering review
Detailed design of the elements standard to every furnace — hot zone, element configuration, insulation package, shell, loading mechanism and control architecture — along with the custom details unique to your process, reviewed with you before anything is fabricated. We run multiple design iterations so customers get exactly what their process needs. Changes are cheap at this stage and expensive after it.
Step 4: Fabrication and control system build
Every furnace is fabricated in our own manufacturing facilities in Denver, Colorado. Welding, machining, custom refractory and metal fabrication on our CNC machines, assembly and testing are all performed by Deltech engineers and technicians across our three Denver locations. Control panels are built in our atmosphere-controlled panel shop to UL 508A standards and listed by Intertek, with the instrumentation and data handling your process actually needs rather than a default package.
Step 5: Testing before it ships
Every furnace is fully function-tested before it leaves Denver, under our ISO 9001:2015 quality system. For a custom build we will also agree a set of performance guidelines with you that the system has to meet before shipment. You can witness that testing by video call, or in person at the factory — which doubles as training for the people who will run it.
Step 6: Delivery, installation support and commissioning
Delivery, installation guidance, start-up support and operator familiarization — followed by a relationship that lasts the life of the furnace. We repair and rebuild our own equipment, and in many cases equipment we did not build.
What can be engineered
Temperature
Deltech furnaces are designed to be operated continuously at their rated temperature — a 1700 °C furnace will run at 1700 °C for long periods. Common ratings are 1200, 1500, 1700 and 1800 °C, and designs for other temperatures are routine. We also build furnaces that reach 2000 °C in air, using zirconia heating elements with a Kanthal Super 1900 preheater and a cast zirconia hot face. Most equipment reaches its top numbers only under vacuum or inert gas, which changes the chemistry of what you are firing.
Atmosphere
Air, inert, reducing or controlled mixtures, with the gas handling, sealing and safety interlocks each one requires. We specify the heating element, sealing and refractory combination that suits your particular atmosphere.
Geometry and loading
Bottom-loading, front-loading, elevator, tube — vertical, horizontal or rotary — bell, tunnel and continuous configurations, sized to the work rather than to a catalog envelope.
Size and capacity
There is no such thing as too small. At the other end, our largest rotary and tunnel kilns run to around 30 feet. Between those, the deciding factor is usually operating economics rather than engineering. Electric is the most controllable and cleanest option up to roughly 64 cubic feet of working volume; past that, the running costs of gas begin to compete. We will walk you through that trade-off for your volume before you commit to a design.
Batch or continuous
Including continuous charge and discharge at temperature, which is usually the hardest part of a scale-up and the reason a bench process stalls on its way to production.
Control and data
Multi-loop programmable control, independent over-temperature protection, optical pyrometry where thermocouples will not survive, and data logging that satisfies a quality system.
Compliance
NFPA 86 for furnace safety, UL 1203 and Class I Division 2 construction for hazardous locations, and ASME NQA-1:2008 quality assurance where the work is nuclear-related.
The processes we build for
- Glass and specialty glass — melting, fining and annealing.
- Technical ceramics — sintering and firing of oxide and advanced ceramics.
- University and national laboratories — research furnaces written to a grant specification.
- Refractories — testing and production under service conditions.
- Catalysis and energy — calcination, reduction, powder processing and the electrification of fired processes.
- Aerospace and materials testing — thermal exposure and qualification at temperatures most equipment cannot hold.
Looking for your process? Browse furnaces by application and process.
Why this is not a leap of faith
We have been doing it since 1968
Deltech is family-owned and still manufacturing in Colorado, nearly sixty years after it was incorporated. The engineers who design these furnaces are the people who answer the phone.
Custom is the main business, not a sideline
Around 90% of what we build is custom in some way. This is not a catalog company that will occasionally take a special order — engineering to a process is the normal path through our shop.
The quality system is real and audited
ISO 9001:2015 certified, with ASME NQA-1:2008 quality assurance available for nuclear-related work and UL 508A listed control systems.
We support what we build
In-house repair and rebuild, replacement elements and parts, and toll firing to 1700 °C in our own facility when you need the result before you need the furnace.
We will tell you when the answer is no
Some processes belong in somebody else’s equipment, and some belong in a standard furnace that costs a third of a custom build. A quote that arrives with that judgment in it is worth more than one that does not.
What to send us
You do not need a finished specification to start. The most useful first message describes the material and the process, the temperature and atmosphere it requires, roughly how much and how often, the utilities and floor space available, and the date the equipment has to be working. If you have a written specification or a grant document, send that instead — we will read it and come back with questions.
Frequently asked questions
What is a custom high-temperature furnace?
A custom high-temperature furnace is designed around a specific process rather than selected from a catalog. The hot zone, element configuration, atmosphere handling, loading method and controls are engineered to a particular material, temperature profile and throughput. Deltech builds these to 2000 °C in air at its Denver, Colorado facility.
How long does a custom furnace take to build?
Small custom builds typically run 12 to 20 weeks, medium builds 28 to 32 weeks, and large custom builds 44 to 48 weeks including design. A written specification with a budgetary figure can often be turned around within 24 hours of the first conversation.
How large a furnace can Deltech build?
There is no practical minimum. The largest rotary and tunnel kilns run to around 30 feet. Electric heating is the most controllable option up to roughly 64 cubic feet of working volume; above that, operating economics begin to favor gas. We will walk you through that trade-off for your volume before you commit to a design.
When do I need a custom furnace instead of a standard one?
When the process does not fit a standard envelope. Common triggers are a temperature above what catalog equipment holds in air, an atmosphere requirement, a work size or geometry that will not fit a standard chamber, continuous charge and discharge at temperature, or a compliance requirement such as hazardous-location or nuclear-related quality assurance. If a standard furnace will do the job, we will tell you.
Can a furnace really reach 2000 °C in air?
Yes. Deltech furnaces reach 2000 °C in an air atmosphere using zirconia heating elements with a Kanthal Super 1900 preheater and a cast zirconia hot face. Most equipment quoting comparable temperatures requires vacuum or an inert gas, which changes the chemistry of the material being fired.
How does the custom furnace design process work?
It runs in six stages: an engineering inquiry about the process, a written specification with lead times and a budgetary figure, a design and engineering review before fabrication begins, fabrication and control system build in Denver, full function testing against agreed performance guidelines before shipment, and delivery with installation and commissioning support.
What information do you need to quote a custom furnace?
The material and process, the peak temperature and required atmosphere, the size and form of the work, how it is loaded and whether the process is batch or continuous, throughput, the utilities and floor space available, any compliance requirements, and the date the equipment is needed. A grant specification or written scope works just as well.
Can you electrify an existing gas-fired process?
Yes — it is an increasingly common request. Replacing a gas-fired kiln or furnace with electric heating means matching the thermal profile and uniformity the process depends on, not simply matching the peak temperature. That is an engineering exercise, and it is one we do.
Do you support the furnace after it is installed?
Yes. Deltech repairs and rebuilds its own equipment and, in many cases, equipment built by others, and supplies replacement elements and parts. Toll firing to 1700 °C is available at the Denver facility when you need a result before you need a furnace.
Where are Deltech furnaces built?
All Deltech furnaces are designed and manufactured at the company’s facilities in Denver, Colorado. Deltech has been family-owned and operating there since 1968.
Tell us about the process.
An engineer will read it — not a form handler. Send what you have and we will come back with questions, a recommendation, and a budgetary figure if we have enough to give you one.
Talk to an Engineer · (888) 506-3653 Email sales@deltechfurnaces.com Send a Process DescriptionDeltech Furnaces · Custom high-temperature furnace design and manufacturing since 1968 · 1007 E. 75th Avenue, Unit E, Denver, CO 80229 · (888) 506-3653 · ISO 9001:2015 Certified · ASME NQA-1:2008 Quality Assurance Available · UL 508A Listed Control Systems · Member, The American Ceramic Society