Normal refractory constructions will result in a moderate temperature of the steel casing (100-150 °C) A hot spot on the steel casing is normally caused by damage of the refractory lining. Sometimes the back up insulaton layers are deteriorated and hot gasses can flow along the steel casing. In case the hot spot covers a large area and at high temperatures, such a hot spot can become dangerous. Especially in case of high process pressures. A complete installaton can easily fail due to a hot spot.
Togeher with the company Orange Refractory Services from Strijen (NL) we can repair hot spots even while the installation stays in operation and continues production. Our unique repair system has been developed in the USA by Industrial Service Contractors (ISC) from Baltimore. Small adaptors are installed around the hot spot. From the outside a special refractory mass is injected into the insulation layers at the inside of the steel casing. There is no need to stop the installation, so no production losses. In this way it is possible to reduce the steel temperature at a hot spot (up to 700 °C) and bring the temperature down to normal levels of 100-150 °C. Repaired hot spots remain at low temperature levels for many years. Only in case of movement of the refractory lining, it may be that repaired spots must be re injected after a couple of years.. Many of hot spots that we have repaired had extra compressed air or water cooling installed. After repair of hot spots such extra cooling can be removed.