Home›Spare parts
Spare parts
Seals, springs, retaining rings, valves. The parts that wear – and that decide whether a spear is overhauled or replaced.
What actually wears
The vessel lasts for decades, the spear does not. On every cycle it is coupled up, flowed through, flushed with hot caustic and hit with steam. That is why the industry association recommends overhauling spear and down tube after seven to eight years – earlier where handling is rough.
The four parts that are replaced in the process
- Retaining rings – on the threadless systems. New as a matter of principle, always, without exception. A reused ring is the cheapest way to build an accident at work.
- Seals and O-rings. Wet them before spear – a sealing ring installed dry is one of the most common causes of leaks at the neck.
- Springs. Overstretched springs turn a keg into a “seeper” that gives off small quantities unpredictably. At an overhaul they go in new, not reused.
- CO₂ valves. From around ten years the rubber begins to come away from the metal core. That creates areas which can no longer be cleaned.
We cut spears to length
A spear only fits if the spear length matches the height dimension H3 of the keg. If the tube touches down, it disturbs cleaning; if it is too short, beer stays in the keg. On special designs and older kegs the standard length does not always match.
We cut to length – dispatch then moves out to two or three working days. For that we need the height dimension H3 of the keg or, failing that, the design, capacity and manufacturer. More on this.
Square seal or O-ring?
That is the second question to settle before every spare parts order. Threaded spears seal with a square seal resting on top, threadless ones with an O-ring – and the latter also carry a retaining ring and a tamper-evident ring, which do not exist at all in the threaded version.
Anyone who mixes those up orders parts that do not fit. How to tell which system you have.
Type A and type G share one stock
Flat spear (A-type) and triangular spear (G-type) are identical inside. Seals, springs and valves are interchangeable between the two – the difference is a three-lobed instead of a round body, which calls for a different coupler. Anyone holding both types does not need a second spare parts store for them.
What is not interchangeable: the coupler. That is what the three-lobe shape is for.
What to watch when installing
Tightening torques are documented for screwed spears: tighten at around 55 ft-lbs, which is about 75 Nm, and re-tighten at around 35 ft-lbs, about 47 Nm. Too little torque and a missing re-tightening are two of the four main causes of leaks at the neck.
No impact wrench. Not when installing and not when removing. A neck thread lasts a keg’s lifetime if handled cleanly – what destroys it is impact pulses and wrong torques, not the number of installations.
And before any work on the spear: release the pressure. Never assume a keg is unpressurised – not even if it has stood for a long time. Residual beer and changes in temperature build pressure back up.