Pre-engaged hydraulic starter

A pre-engaged hydraulic starter offers guaranteed reliability, no matter how challenging or unpredictable the environment. This truly independent start method can be specified as the only starting system or as a back up to electric or air starting. The major advantage of a pre-engaged starter motor is that it can be certified to the ATEX safety standards.


What is pre-engaged starting?

The key difference between inertia and pre-engaged starting is that the latter only initiates the high speed rotation once the pinion has fully engaged with the ring-gear. There is no collision between a rapidly rotating pinion and the stationary ring-gear.

The movement of the pinion is often controlled by a relay valve. This moves the pinion along the shaft until it connects with the ring-gear. Once engaged, the full hydraulic pressure of the starting system is then released to crank the engine.


ATEX approved pre-engaged hydraulic starter

If you operate an offshore platform or underground mine ATEX certification means safety. The goal of the ATEX safety standard is to remove the risk of fires or explosions being caused by an accidental source of ignition. For an engine starting system to meet this goal it has to use a pre-engaged starter motor.

Pre-engaged starter motors are specifically mentioned in both BS EN 1834-1:2000 and BS EN 1834-2:2000, two of the standards on which ATEX is built. These standards say:

“mechanical starters shall be of the pre-engaged type”

IPU’s M22 and M28 pre-engaged hydraulic starter motors are fully certified and approved to BS EN1834-1 and 2 standards through a 3rd party assessment. This means they are safe for use in potentially explosive atmospheres such as oil & gas platforms and underground mines.


Robust and reliable

IPU’s hydraulic starter motors combine quick acceleration with high torque output. This provides guaranteed starting even after long shut down periods, in extreme temperatures and in damp or humid conditions.

Unlike models from other companies, IPU’s hydraulic starter motors are manufactured with a cast iron outer casing. This ensures they are resistant to wear, protects the internal components and eliminates any outer aluminium content. ATEX recommends against using aluminium; in fact it is difficult for a starter with an aluminium casing to pass ATEX’s constructional safety requirements.

IPU’s systems can be equipped with electric motor and/or engine driven recharge pumps and solenoid valves for remote or auto start options. However, IPU’s hydraulic starting systems also come with a hand pump for manual charging and foot start valve as standard.

Video of a pre-engaged hydraulic starter

Our video shows how the pinion engages with the ring-gear before cranking can start.


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