Thermo-products from JSI are a range of temperature-stable seals, packings and sleevings designed for long-term operation at temperatures up to 600 °C. The company’s origins and the many decades of experience in the textile industry provided the engineering background to develop the manufacturing techniques.

From the large variety of types and the diverse finishes available, it is possible to engineer the best heat insulation to meet the customer’s requirements to an optimum. The following types of thermo-products are available:

THERMOSEAL sealing ropes are made by knitting texturised glass yarn, with or without an inner core. The glass filler yarns can be varied to meet the required compressibility for the particular application*). The outer sleeve construction can also be appropriately modified to meet the final sealing properties specified.

THERMOSEAL sealing ropes are characterised by a high degree of flexibility for a perfect fit around small radii. These products are ideally suitable for static sealing applications in dry environments, e.g. as seals for hatches and doors in furnaces and ovens, industrial boilers and solid-fuel stoves, or as seals in domestic boilers and heat-exchanger casings.

*) The degree of compressibility is given as a percentage of the overall seal diameter and is determined by a certain standard test method. More detailed information on this is available on request.

THERMOTAPE sealing tapes are manufactured from resilient texturised glass yarns. These products are characterised by excellent sealing properties.

THERMOTAPE is available as a robust construction in a large variety of dimensions. THERMOTAPE is also supplied in finer constructions used primarily to prevent metal to metal to glass contact. To help reduce the end-user’s costs as well as to make fitting over bolts and studs easier, THERMOTAPE L products are also available as a laddered tape construction with an open section down the middle.

THERMOTAPE sealing tapes are used for such applications as e.g. casing seals for doors and inspection windows in solid-fuel or wood-fired boilers and stoves. THERMOTAPE C with channelled sections is a special development to facilitate fitting around the window of glass-fronted appliances.

VIDASEAL has a final overbraid of fine continuous-filament glass yarn applied to the texturised glass seal. In comparison with other thermo-products, VIDASEAL is characterised by higher mechanical strength and an enhanced surface finish. Both round seals and P-profiles are available in a wide range of diameters. In each case, the individual dimensions and the compressibility can be tailored to exactly meet the requirements of the application.

The high flexibility and conformability mean that seals made from VIDASEAL can closely follow the smallest internal radii without any loss of sealing performance. Depending on the type of seal, VIDASEAL products are either heat-treated or coated. The operating-temperature range for these seals is limited by the finish.

Examples of use for VIDASEAL products are for sealing the window on glass-fronted domestic heating appliances and as the seal around the opening in catering ovens and laboratory furnaces.

MARSEAL is a round thermo-product manufactured from glass yarns coated with a silicone elastomer and reinforced by either knitted glass yarn, stainless-steel wire or a combination of the two. This gives MARSEAL maximum dimensional stability and resilience such that these seals will withstand both the pressures from a lightweight door closing as well as the pressure from heavy-duty cast iron. The reinforcement ensures the seal will return to its original profile when pressure is released.

THERMOGUARD protective sleevings are produced from knitted texturised glass yarn and are available with different wall-thickness dimensions, a large range of diameters and with an optional coating of a silicone elastomer.

The outstanding properties of THERMOGUARD sleevings are used as thermal protection jackets and heat insulation sleevings. THERMOGUARD provides an economic and effective protection against heat, metal splashes as well as heat losses.

THERMOGUARD sleevings are widely used to protect steam pipes and compressed-air lines, hydraulic hoses and fuel lines, as well as for electric cables.

HYPERFOIL is a woven glass fabric laminated with aluminium foil exhibiting excellent heat-reflection and thermal insulation properties. It can be cut and shaped to provide covering and protection for specific components.

HYPERFOIL can be supplied in tape form for use in fire-retardant and heat-resistant cables, heat barriers and screens, as well as incombustible heat reflection in flexible ducting.

REFLECTOTHERM is a range of highly reflective, woven-glass reinforced sleeving. The outer aluminium foil maintains a highly reflective finish while the inner layer of woven-glass fibre provides significant thermal insulation. The sleeving is formed by folding the material and stitching the edge with an aramide or fibreglass thread. REFLECTOTHERM sleevings are widely used for protecting components from both radiant and conductive sources, typically for hoses, fuel lines, hydraulic lines and wiring/control cables.