Heat exchanger gaskets create a seal between mating components, helping to prevent external leakage and keep separate process streams from mixing. Their precise function depends on whether they are installed in a shell-and-tube, plate-and-frame or other heat exchanger design.
Gaskets may seal the exchanger’s outer perimeter, divide individual flow passes or direct hot and cold media through separate plate channels. Correct selection therefore depends on more than the gasket dimensions. The construction, materials and geometry must suit the process media, temperature, pressure, thermal cycling, flange arrangement and available compressive load.
Dobson Gaskets manufactures custom and replacement heat exchanger gaskets in standard and non-standard configurations, including complex profiles with pass bars and partition bars.
Metal-jacketed gaskets consist of a metallic jacket surrounding a compressible filler. The outer jacket provides mechanical protection and temperature resistance, while the filler helps the gasket conform to the sealing faces.
Also known as Kammprofile gaskets, Camprofile gaskets use a serrated metal core with conformable facing layers, typically graphite or PTFE. The solid core provides stability under compressive loading, while the softer facings accommodate minor irregularities in the sealing surfaces.
Plate heat exchanger gaskets fit into shaped grooves around individual plates. Their profile controls the route taken by each fluid while maintaining separation between the hot and cold circuits.
A heat exchanger gasket may perform several sealing functions within the same assembly:
External leakage and internal cross-contamination are different failure modes. Correct gasket geometry is therefore as important as selecting a material that can withstand the operating conditions.
A material’s maximum temperature should not be treated as the operating limit of the finished gasket. Pressure and temperature capabilities cannot be determined from the gasket type alone. The complete construction, dimensions, process media, flange condition and available compressive load must all be considered.
Yes. Dobson Gaskets can use an existing gasket as the basis for manufacturing a replacement, including complex shapes and pass-bar configurations.
The sample should be checked for compression, distortion, corrosion and missing material because a used gasket may no longer represent its original dimensions. An equipment model, drawing, part number and operating data should also be supplied where available. This allows the sample to be verified rather than copied without reference to the application.
There is no single material that is best for every steam heat exchanger. Selection depends on the steam temperature and pressure, condensate chemistry, thermal cycling, flange design, surface condition and available bolt load.
Graphite-faced Camprofile gaskets and suitable metal-jacketed constructions may be considered for shell-and-tube steam duties. However, the complete joint and operating conditions must be assessed before the gasket construction, core, jacket, filler or facing material is specified.
Repeated leakage does not necessarily mean that the gasket itself is defective. Possible causes include an incompatible material, incorrect gasket geometry, insufficient or uneven bolt load, damaged sealing faces, flange distortion, misaligned pass bars or temperature and pressure excursions.
The installation method and tightening sequence should also be checked. Where leakage recurs, the complete joint and operating history should be investigated before another replacement gasket is installed.
Material selection is fundamental to the performance and service life of a heat exchanger gasket. Metallic components provide the structural strength and stability required to withstand compressive loading, pressure and thermal cycling, while fillers and facings help the gasket conform to the sealing surfaces and maintain an effective seal.
Each component must be compatible with the process media on both sides of the exchanger, as well as the operating temperature, pressure, flange materials and available seating stress. Material limits should never be assessed in isolation, as the performance of the finished gasket depends on the complete construction and bolted joint.
| Material family | Selection considerations |
| Stainless steel | Offers general corrosion resistance, but the grade must suit the media and temperature |
| Low-carbon steel or soft iron | An economical option for compatible duties, with limited resistance to corrosive media |
| Copper | Soft and conformable, but compatibility with chemicals and adjoining metals must be checked |
| Nickel alloys | Considered for elevated temperatures or aggressive chemical conditions |
| Monel | Used for selected chemical, marine and hydrocarbon applications |
| Titanium | Selected where the particular corrosion environment justifies its use |
| Duplex and super duplex | Considered where greater strength and resistance to chloride environments are required |
| Material | Principal characteristics | Important considerations |
| Flexible graphite | Conformable, resistant to high temperatures and capable of retaining load | Suitability for oxidising media and atmospheres must be checked |
| PTFE | Provides broad chemical resistance | Creep, temperature capability and load retention vary by PTFE type |
| Compressed non-asbestos fibre | Suitable for many general industrial applications | Performance limits depend on the individual material grade |
| Specialist facings | Selected for particular chemical or thermal duties | Must be assessed using verified product data |
Our highly experienced technicians can advise you on the best sheet materials and manufacturing processes for a wide range of gasket applications.
We supply a vast range of gasket materials, available to buy directly or order from us. For more information visit the Gasket Sheet Materials page