Several manufactures of jaw crushers claim crusher to 10 mesh on a single pass. These include: TM Engineering, BICO, and others.
While this may be true for a new crusher, this will quickly wear the plates and is a slow and inefficient way to crush. It is far better to use the jaw crusher for what they are inherently good at (crushing larger sizes) and use a secondary crusher for finer crushing and grinding (such as a cone crusher or roll crusher).
Hi there, I'm new to this site. I know that the original post is very old but you may find the following information and products of interest.
Our company has been designing and manufacturing mineral sample preparation and sampling equipment in Perth, Australia for over 25 years.
You'll find our equipment in most of the major commercial laboratories around the world.
Sample preparation for gold samples, where the distribution and size of gold particles is often irregular, usually demands that a relatively large sample weight is taken to produce a representative sample for analysis.
Traditional sample preparation of gold samples incorporated multiple stages of coarse particle size reduction followed by subdivision of the sample prior to final fine pulverising. This technique developed because of the limited equipment options available to laboratories. As a result significant errors are introduced and the final sample size being pulverised is a small fraction of the original sample weight.
Three significant developments have occurred in the last 25 years to significantly improve sample preparation of gold samples:
- large capacity fine pulverising, - fine jaw crushing, and - whole sample coarse pulverising.
In the mid-1980s an Australian manufacturer developed large capacity pulverising bowls which had the ability to reduce samples with a mass of 1.5 – 3.5 kg to a nominal 0.075 mm product in approximately 3 to 5 minutes. Laboratories were able to produce a large homogeneous pulverised sample which significantly reduced the error in sampling. However exploration and mine samples are usually 7 to 10 kg and the sample requires a subdivision stage following crushing to produce the 3.5 kg for the pulverising step thus introducing potential for significant error.
The development of fine jaw crushing allowed particle size reduction to minus 2 mm which reduced the subdivision error of the bulk sample prior to fine pulverising. Subdivision of the crushed sample at minus 2 mm still results in potential sampling errors where the gold particles are not sufficiently liberated to be representatively sampled. Clearly the best option would be to reduce the particle size small enough to ensure a representative sample prior to final pulverising.
Continuous mills offer a partial solution but are relatively slow and subject the sample to differential pulverising prior to subdivision. Clearly this does not provide the best solution for routine laboratory applications where high volumes of samples are to be processed.
The recent development of a large capacity coarse pulverising system allows samples of up to 10 kg to be reduced to minus 0.25 mm prior to subdivision and fine pulverised to minus 0.075 mm.
Laboratories now have the necessary equipment to perform reliable large capacity sample preparation of gold samples. The exact choice of sample preparation scheme may still depend on particular ore types but the need for multiple crushing and subdivision stages is redundant.
Please feel free to download the paper at the following site to read more about these developments (it's titled Large Capacity Sample Preparation)
If you want to check out some really interesting developments in the area of sample preparation automation and robotics then look at some of the other videos on this page.
Sample crushing and grinding and other unglamorous, repetitive and often hazardous tasks are now being done by industrial robots in most of Perth’s commercial mineral laboratories.
The Perth robot revolution started about 9 years ago and now the city is arguably the world centre of commercial laboratory automation. Today 30 industrial robots are performing jobs that were previously extremely manually demanding and often in hot, dusty and noisy environments.
In fact, by the end of this year all the major commercial assay labs in Perth will be using robots to meet the demand for more flexible and reliable testing systems in the face of increased labour and production costs. Robots allow them to maximise turnover with a relatively short payback period whilst achieving higher quality results.
Even in in the current downturn exciting times lie ahead in the field of crushing and pulverising.
Fireguy wrote: While this may be true for a new crusher, this will quickly wear the plates and is a slow and inefficient way to crush. It is far better to use the jaw crusher for what they are inherently good at (crushing larger sizes) and use a secondary crusher for finer crushing and grinding (such as a cone crusher or roll crusher).
Our company manufactures a fine jaw crusher. The JC2500 jaw crusher is able to easily crush 110mm (4") lump ore, drill core or drill chips to 90% less than 2mm (10 mesh) in a single pass at a rate of about 180kg per hour (400 lb/hr).
The jaw gap adjustment process on this crusher is easy to do so regular monitoring and closing of the gap will compensate for any wear in the plates. Users find the hardened steel jaw plates very long lasting.
Ideally, single pass fine jaw crushing is the most efficient means to reduce sample size prior to subdivision and fine pulverising.
We have found that the majority of our customers (which include the world's major commercial laboratories and mining & exploration companies) no longer use rolls crushers, cone crushers or disc pulverisers for gold sample preparation due to cross-contamination and smearing issues, especially where coarse gold is present.
Zhengzhou Vipeak Heavy Industry Machinery Co., Ltd has long been one of the best powder processing machinery companies in China, Welcome all the customers from worldwide to browse our website and choose our machinery. Being a leading company in Industrial powder processing, Engineering Stone crushing and Construction Sand Making, Zhengzhou Vipeak Heavy Industry Machinery Co., Ltd is a high-tech mining machinery company in China. Our service has expanded to the entire world, almost including 75 countries.From Engineering Stone, Construction Sand to Engineering Powder, All Equipments from VIPEAK exert great productivity and stability on working sites, make the customers satisfied. We strongly feel that customers do not only need equipments with good performance, but in the hope of their efficiency, their benefit and their competitive power. so high value added equipments have been produced.We have never been satisfied; our customer’s satisfaction is our utmost objective. http://www.grinderpro.com http://www.crushingmill.com
Jaw Crusher Application of Jaw Crusher One of the most popular stone-crushing equipments in the world, Jaw Crusher is ideally suitable for primary and secondary crushing. The highest anti-pressure strength of crushed material is 320MPa. It is widely used in mining, metallurgy, construction, highway, railroad, and chemistry industries and etc. Many models are available according to your different fineness requirements. http://www.grinderpro.com/Jaw.html (Jaw Crusher)
......this will quickly wear the plates and is a slow and inefficient way to crush. It is far better to use the jaw crusher for what they are inherently good at (crushing larger sizes) and use a secondary crusher for finer crushing and grinding (such as a cone crusher or roll crusher).
I agree that 'steeping it down' is the way to go. One fell swoop doesn't work well.
I do not think it is a good way to crusher to 10 mesh by a jaw crusher,the minumum particle size of jaw crusher producede by Zoneding Machine is about 20mm,then you can use cone crusher or ball mill to crush materials to 10 mesh. Here are the machines producede by Zoneding Machine: cone crusher roll crusher ball mill