Our Hot Frame Guillotine design is the best commercial and technical fit for isolation applications where reliability is a concern.

Bachmann Dampjoint engineers have been designing and supplying the unique Hot Frame Guillotine to the industry for decades. This proven, rugged design is specifically tailored for isolation applications where reliability and performance are crucial. Our Hot Frame Guillotine damper has two key features: our worryfree flexible-seal combined with our engineered blade design. These two innovations completely eliminate the need for a frame seal cavity and ensure dual seal contacts within the duct. This also allows seal components to be kept entirely inside the duct, where the flue gas keeps them hot – hence the “hot frame”.


  • 100% isolation with seal air
  • Self cleaning blade seal
  • No risk of dust accumulation
  • Mitigation of corrosion issues
  • Increased seal life and durability
  • No bottom frame purge required
  • Reduced capital, operating, shipping and field assembly costs
  • Fully isolated bonnet
  • Low pressure drop
  • Self-cleaning drives with superior reliability

These features have significant benefits:

  • 100% isolation – Indeed, when seal air is used, our Hot Frame Guillotine damper allows 100% isolation. If no seal air is used, 99.5% isolation can be achieved.
  • Self-cleaning blade seal – The dual knife blade end design allows dual seal contact whiler emoving any accumulation of dust, thus guaranteeing isolation integrity.
  • No risk of dust accumulation – There is no seal cavity where dust can accumulate.
  • Mitigation of corrosion issues – There is no “lower temperature” seal cavity where acid condensation can occur.
  • Increased seal life and durability – Our blade seals are engineered for a smaller 1/8” deflection, versus the large forced deflection of 3/8” to 3/4” in conventional guillotine flat plate blade designs. This reduces cycle fatigue stress and increases the lifespan of the seals. Also, mitigation of dust accumulation and acid condensation drastically reduces seal wear.
  • No bottom frame purge required – Since our Hot Frame Guillotines do not have a bottom frame seal cavity, no purge, extra ducting or additional maintenance are required.
  • Minimization of cleaning, maintenance and replacement costs – With reduced wear from corrosion and dust accumulation, our design is truly worry free!

Our guillotines are also equipped with unique bonnet throat seals, which are the top seals where the blade enters the bonnet. These seals are engineered for only end-of-stroke contact and deflection, which significantly extends throat seal life.

In addition, our guillotines have a structurally reinforced blade. With our design, there is no need for internal bracing to control blade deflection, as is usually necessary in conventional flat plate blade designs.

This feature has the benefit of:

  • Reduced capital costs – Less material is required in the Hot Frame’s construction.
  • Smaller pressure drop than a flat plate design – Flat plate blade guillotines require significant grid systems that leads to increased pressure drop. This is not the case with our Hot Frame guillotines.
  • Easily spliced blade – This means that the damper blade can be easily segmented, when necessary. This can have a significant impact on shipping costs and ease of field assembly.

Finally, our design includes a rack & pinion drive, with a rigid chain. This allows our drives to have no flexible parts, eliminating any risks of the chain kinking. Also, our rack and pinion drives are self-cleaning, which is crucial in dusty application. This enables our guillotine design to have superior drive reliability.

As you can see, our Hot Frame Guillotine isolation damper has many features addressing specific application issues. This makes our design the best technical and commercial solution for applications where reliability is a concern.

Flex Seal Guillotine Damper

Our Engineers have been designing and supplying the unique Flex-Seal Guillotine to the Power Industry for over 30 years.

The Flex Seal Guillotine design addresses key issues facing coal fired power plant flue gas isolation applications


  • Engineered Blade with thick (6” and up) structural components that allow controlled seal deflection
  • 100% flue gas isolation (Optional Seal Air Fan Required)

Rack & Pinion Drives for Guillotine dampers

Our Rack & Pinion Drive System for guillotine dampers is the best commercial and technical fit for applications where reliability is a concern.

The drive system on our guillotine dampers consists of an electro-mechanical multi turn actuator, which drives the heavy-duty sprockets, keyed to a stainless steel shaft. The stainless steel shaft ensures increased corrosion resistance in the stuffing box areas, preventing rusting-in place for dampers that are infrequently opened/closed. The sprockets engage and move the pin rack(s), which are open, self-cleaning “rigid chain” racks attached to the blade. The rigid pin racks have none of the flexing problems commonly associated with chain drives. The sprockets are facing the blade, thus allowing the free thermal expansion of all components, including the blade. This drive design enables our guillotine dampers to have superior drive reliability, even in the most demanding in high temperature and dusty applications.


  • Self-cleaning drive
  • Superior reliability in high temperature and dusty environments