Wear note
Cone CSS notes
Closed side setting notes belong with the liner pack, not in a separate PDF graveyard.
By Mr Pieter Botha, Cone circuit adviser
Pieter Botha is the go-to adviser on mantle and concave geometry for secondary cone crusher circuits across Gauteng.
AuthorWhy this matters on the plant
Too many crews treat closed side setting as a static number, scribbled once on a form and forgotten in a folder. In reality, your actual CSS in the chamber is just as vital as the liners themselves for throughput and end-product quality.
Measuring true CSS on plant
I have seen teams take CSS readings off the gap indicator or rely on last week’s clipboard figure, but you need to measure it properly with each liner change or chamber adjustment. The only way to know your real closed side setting is to stop the crusher, lockout, and use lead or soft solder to crush through the chamber. That measurement, not the hydraulic gauge setting or control panel readout, gives your true CSS under spring tension with the current liner wear profile.
Remember, South African dust and fines can pack into the chamber, distorting readings if not cleaned out. Eskom power cuts are a hazard, so always finish your measuring with power isolated and the plant secure.
CSS and liner pack working together
Your liner pack and CSS are a matched set. Each new set of bowl liners, or any change in chamber profile, will alter the geometry and nip angle in your crusher. If you simply bolt in new parts without checking CSS, you risk over-tight chambers leading to excessive fines, or too-wide settings causing oversized, flaky product.
A common mistake here is reusing old CSS notes for a new liner profile. OEM chambers vary, and even a small shift in toe or throat changes your effective CSS. After each liner change, measure again and record the new value right in the liner log, not on a separate sheet that gets lost. Do not trust 'set-and-forget' habits, liners and chamber shape change during the campaign due to work hardening and wear.
Common errors we see in the field
Across plants from the Highveld to the coast, I have seen recurring mistakes when it comes to CSS:
Crews sometimes skip measuring after a night shift liner change, leading to a mismatch between chamber and feed.
Some rely on hydraulic pressure or motor amps alone as a CSS proxy, but these do not account for wear or stuck tramp.
Another error is using the same CSS for different feed types, ignoring the impact of sand content or feed shape.
Lastly, many teams neglect to update the liner pack records, so the next shift has no idea what the true chamber setting is.
- Skipping actual measurement after liner change
- Using only gauge values, not physical measurement
- Forgetting to allow for wear or work hardening
- Not recording CSS with the liner pack
- Re-using old notes for new chamber profiles
Practical steps for reliable CSS record keeping
Organise your liner pack notes as a living record, kept with the spares in the parts yard or at the crusher, not buried in a filing cabinet. Record the measured CSS after each liner change or adjustment, including the chamber profile and wear reading. South African sites often cycle through different feed types and materials, make a habit of logging any CSS changes tied to those campaigns.
If you run multiple liners (say coarse and fine profiles for seasonal work), keep a simple board or folder with last measured CSS, dates, liner spec, and crew initials. That way, anyone on the team can see the chamber’s current working setting at a glance. Email queries through our contact form if you need template sheets or advice on best practice for your site.
Related parts: Bowl Liner. You can also browse all parts and plant guides.
What our Crusher Wear Parts customers say
Verified Google reviews