Thermal Insulation May Save Your Engine. Here’s Why…

Fire is a real threat in any situation, but in mining it presents a particularly dangerous problem due to the confined spaces or large equipment. Depending on the particular operation of course. Coal mines carry the added risk of spontaneous combustion which increases temperatures in loading or piling areas. Add to this large rubber tyres, a huge amount of diesel and an ignition source (engine turbo) and the situation may quickly turn into a disaster. Thermal Insulation for engines from Delakufa can prevent this disaster from happening.

Mega machines obviously don’t need much to set themselves on fire as the heat generated under the engine hood only needs a burst fuel line or leaking oil pipe to trigger an event resembling Guy Fawkes and the millennium celebrations all in one. In the worst way.

That brings us to the reason why thermal insulation of your engine is a critically important and pro-active measure against equipment fire risk.

Thermal Insulation for engines from Delakufa Thermal Protection
Enter Delakufa Thermal Protection

The explicit purpose of Thermal Insulation from Delakufa on mobile equipment is to isolate the hot parts from everything else:

  • The flammable vapours and electrical systems.
  • Personnel who might be present under the hood of a large (or small) combustion engine from time to time.

The glowing hot turbo is the primary ignition source in most mobile equipment fires. By isolating this ignition source, you can prevent a pending Blitzkrieg between the radiator and the flywheel.

Delakufa Thermal Protection offers custom engineered thermal insulation systems for diesel engines. Using technologically advanced materials to manufacture each individual part by hand to fit the requirements of unique applications. We ensure optimal insulation and resilience under severe operating conditions. We measure and fit each cover according to stringent design standards. We’ve achieved temperature reductions of up to 60% in under hood conditions on mobile equipment.

Thermal Protection vs Fire Suppression

One could counter that “once the machine is on fire,” the thermal coverings might inhibit the fire suppression system from cooling heated surfaces. But this is like saying a broken ankle is harder to treat while wearing a medical boot. So we should rather replace the bucket on a front end loader with a water tank in case it catches fire…? Looks to me that the case for Fire Prevention Systems rather than Fire Suppression Systems is a no brainer.

…it was found that the fire caused by oil spilling on the exhaust manifold after a hydraulic hose chafed through, was sufficiently contained by the Thermal Cover to cause no secondary damage or set off the automatic fire suppression system. The machine could be made safe and put back in production within hours after installing a new hydraulic hose.

report by the Department of Mineral Resources (DMR) 2019 after a blast hole drill caught alight at one of the large iron ore mines in South Africa.
Thermal Insulation for engines from Delakufa thermal protection systems protect mine and plant machinery against damage from heat or fire
What are other benefits of using Delakufa Thermal Protection Systems?

By isolating hot components with Thermal Insulation for engines from Delakufa, you not only illiminate fire and personnel risks. You also extend the life of other components under the hood by reducing radiated heat that destroys plastics and insulating materials over time. Components such as plastic tubing, rubber hoses, electrical wiring and painted surfaces all suffer heat stress after prolonged exposure.

Obviously, personnel safety is a very important benefit of thermal protection systems. Who likes to pick up a nasty burn every time you need to check something in the engine bay, right? Fitting turbo and exhaust covers may actually reduce the use of “creative vernacular” amongst service personnel. Alas, that theory has not been proven yet. Having hot surfaces isolated will however reduce service times by reducing the cool down period before work can commence. Efficiency.

But there’s more… performance.

Thermal insulation of the hot parts of an engine improves the performance and longevity of the engine. It does so by reducing induction temperatures. By reducing under-hood temperatures, the induction system takes in cooler, denser oxygen-rich air. By containing the heat of the exhaust gases within the exhaust system, and away from the intake path, the engine runs more efficiently. This also prevents a thermal pump cycle from forming where the ambient temperature increase causes harmful engine temperature spikes.

Thermally insulated turbo and exhaust systems show improved performance figures over that of non-insulated engines. This is because heat stays in the exhaust gasses within the exhaust system. The turbocharger works better because of the expansive nature of gas relative to temperature. In other words, the more heat retained in the exhaust gas, the more efficient the turbo. The turbocharger’s impeller acceleration increases with this increase in pressure and flow rate at a given RPM. This equals faster spool up of the turbocharger with less lag and therefore more efficiency.

We’ve specifically designed Delakufa turbo and exhaust covers to reduce “hot spots” in the engine bay. It does this by preventing localized thermal expansion (and contraction) of components. These covers are non-porous and will prevent splashed water from reaching hot components during operation. This will prevent warping and cracking due to rapid cooling. Uneven thermal expansion of components causes stress in engine parts even under normal heating and cooling conditions.

Insulating all hot components reduces this factor greatly. This uneven expansion is a common cause of head gasket failure. Especially in engines utilising aluminium components with a greater differential temperature expansion profile. The heat difference between various parts of the engine may cause warping of the cylinder head or exhaust manifold. This leads to warpage or premature failure.

Thermal Insulation for engines from Delakufa thermal protection systems protect mine and plant machinery against damage from heat or fire
Thermal Insulation for engines from Delakufa thermal protection systems protect mine and plant machinery against damage from heat or fire
What does the research say?

According to research regarding the impact of Thermal Insulation on component life cycles, the resultant increase in Exhaust Gas Temperature (3%-5%) from fitting thermal insulation on the exhaust system is negligible. Turbo chargers’ temperature related issues are rather from lean burning conditions than they are from any external factors.

Thermal insulation for engines offer turbo chargers protection from water splash and other temperature fluctuations. Researchers have found devastating degradation impact on metals during heating and cooling cycles. Gradual temperature changes allow for molecular stress relief in metals. Cast iron (that most large turbo chargers are manufactured from) survives well at consistently maintained temperatures, but is prone to stress fractures or metal fatigue when subjected to rapid temperature drops. The related heat expansion of this material will cause increased component wear when placed under stress at below optimal temperatures.

“[…under heated conditions] cast iron doesn’t stretch or bend. However, if cast iron is heated to 1,200° F (648°C), it will take on an artificial yield point allowing it to stretch and relieve confined contraction stress.”

Engine Builders Magazine 2002/05
Delakufa is the smart choice

The fitment of Delakufa Thermal Protection covers will therefore not adversely affect the service life of a diesel engine and its components. Provided everything is functioning within manufacturers specifications regarding fuelling and EGTs, of course. All this despite the increase in Exhaust Gas Temperature (EGT) caused by retaining more heat energy in the exhaust gas. It is, however, necessary to observe abnormal EGT’s caused by incorrect fuelling and the impact on turbo shaft and impeller expansion relative to the bearings and housing material.

Finally, it should be noted that durability and performance are prioritised during manufacturing and installation of the Delakufa Thermal Protection covers to ensure optimal service life despite the challenging application. The proprietary multi layered construction, offer characteristics that will withstand extreme heat conditions while additional non-porous layers prevent soaking and vibration damage.

Delakufa thermal protection systems for mine and plant machinery

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