Abstract: The present disclosure relates to a control unit (8) for controlling reactivation of a lean NOx trap (LNT) disposed in an exhaust system (3) connected to an internal combustion engine (2), the control unit (8). The control unit (8) has at least one processor (11) configured to generate a reactivate flag (RF) for the LNT (6). A memory device (12) having instructions stored therein is coupled to the at least one processor (11). The at least one processor (11) is configured to generate the reactivate flag (RF) when the exhaust gas supplied to the LNT (6) is lean and an LNT temperature (TLNT) is greater than or equal to a predefined LNT temperature threshold (T1). The present disclosure also relates to a method of controlling reactivation of the LNT (6). The present disclosure also relates to a vehicle comprising reactivation control apparatus.

Abstract: An exhaust system for an internal combustion engine (28) for controlling the release of undesirable emissions from the engine comprises an exhaust pipe (32) for receiving an exhaust flow from the engine, an SCR catalyst (48) arranged in the exhaust flow and means (80) for determining the temperature of the SCR catalyst. A NOx absorber (38), such as a diesel oxidation and NOx absorber catalyst (DONAC), is located in the exhaust flow at a position upstream of the SCR catalyst (48) for absorbing and releasing NOx contained in the exhaust flow. Means is provided for controlling the NOx absorber (38) so as to control the release of NOx to the SCR catalyst (48) in dependence on the temperature of the SCR catalyst, thereby to effect active management of release of NOx from the DONAC (38).

Abstract: An exhaust system for an internal combustion engine (28) for controlling the release of undesirable emissions from the engine comprises an exhaust pipe (32) for receiving an exhaust flow from the engine, an SCR catalyst (48) arranged in the exhaust flow and means (80) for determining the temperature of the SCR catalyst. A NOx absorber (38), such as a diesel oxidation and NOx absorber catalyst (DONAC), is located in the exhaust flow at a position upstream of the SCR catalyst (48) for absorbing and releasing NOx contained in the exhaust flow. Means is provided for controlling the NOx absorber (38) so as to control the release of NOx to the SCR catalyst (48) in dependence on the temperature of the SCR catalyst, thereby to effect active management of release of NOx from the DONAC (38).

Abstract: The exhaust system of an internal combustion engine is periodically dosed to recharge an SCR catalyst with ammonia. If dosing is scheduled and exhaust gas temperature is too low to ensure recharging, a forced increase in exhaust gas temperature is effected for the period of dosing. A diagnostic to confirm correct operation of a catalytic converter may advantageously run at the same time.

Abstract: The exhaust system of an internal combustion engine is periodically dosed to recharge an SCR catalyst with ammonia. If dosing is scheduled and exhaust gas temperature is too low to ensure recharging, a forced increase in exhaust gas temperature is effected for the period of dosing. A diagnostic to confirm correct operation of a catalytic converter may advantageously run at the same time.

Abstract: A process for counter gravity sand casting including providing precision cores in a sand mould supported in a casting machine for rotation about a horizontal axis through the center of the mould, providing primary casting risers fed by a launder section, a pressure riser connected to the launder section and the primary risers, rising upwardly beside the mould, whereby on rotation the molten metal in the pressure riser will maintain an internal constant pressure in the mould until the casting risers are upper most, so as to maintain the internal pressure during the cooling of the mould.

Abstract: A composite shut-off means for casting moulds, including a sliding closure made of sand and a compressive refractory material. The sliding closure has a passageway passing through it so as to allow the selective passage of molten metal there through, and a filtering means for the molten metal that filters the metal as it passes through the passageway. The means for retaining the sliding closure, are attached to the mould, so that in use, the mould can be closed and sealed by the sliding closure, and removed from the launder.

Abstract: A segmented die assembly for the casting of a metal object, the die assembly incorporating chill segments that are cooled using oil and/or water and/or air, the segments being interconnected and moved by actuators under the control of a Fuzzy logic module, wherein in use the assembly ensures that the chill maintains contact with the surface of the casting as it solidifies.

Abstract: A method of providing an iron cylinder liner (1) for incorporation in a cast aluminium block for an internal combustion engine, including the steps of placing the liner (1) in a heated fluidised bed so as to simultaneously clean and heat the liner, and then positioning the cleaned and heated liner on the sand barrel core (2). The barrel core having been sized to accept the heated and thus expanded liner, which will subsequently cool and retract locking the liner onto the sand core in the correct position, in readiness for casting of the aluminium cylinder block.

Abstract: A process for counter gravity sand casting including providing precision cores in a sand mould supported in a casting machine for rotation about a horizontal axis through the center of the mould, providing primary casting risers fed by a launder section, a pressure riser connected to the launder section and the primary risers, rising upwardly beside the mould, whereby on rotation a the molten metal in the pressure riser will maintain a internal constant pressure in the mould until the casting risers are upper most, so as to maintain the internal pressure during the cooling of the mould.

Abstract: An engine block mold, including at least one barrel slab core (10), the or each barrel slab core (10) including a slab portion (12), and at least one barrel portion (14) adapted to receive a cylinder liner (1), wherein the barrel portion (14) of the or each barrel slab core (10) has an outer diametral taper along at least a portion of its length, and the or each liner (1) has a substantially matching internal diametral taper along at least a portion of its length. Inserting the or each slab barrel core (10) with the or each liner (1) disposed upon it, into a substantially completed mold casing, filling the mold, and then machining the cylinder liners (1) so that they have a substantially constant internal diameter along their length.