About Crushers
Q: What is the difference between a jaw crusher and a cone crusher? A: A jaw crusher applies compressive force between a fixed jaw and a moving jaw and is typically used as a primary crusher for coarse rock. A cone crusher uses gyratory compression between a conical head and a concave bowl, typically as a secondary or tertiary crusher for producing smaller, consistent product sizes.
Q: What crusher produces the best-shaped aggregate? A: Vertical-shaft impact (VSI) crushers and horizontal-shaft impact crushers both produce well-shaped cubical aggregate. VSI crushers are particularly favored for high-quality manufactured sand (m-sand).
Q: How much crusher capacity do I need? A: Required crusher capacity depends on your production target, feed size distribution, product size requirements and circuit configuration. WSHT engineers can help you size the right crusher for your project.
Q: What is closed-side setting (CSS)? A: Closed-side setting is the smallest gap between the crushing surfaces at the discharge end of a crusher. CSS determines the maximum particle size of crusher product and is adjustable on modern jaw and cone crushers.
About Screens and Conveying Equipment
Q: What type of screen should I use for my aggregate or ore sizing? A: For general aggregate sizing and scalping duties, circular-motion inclined screens are most common. For high-tonnage applications, banana screens (multi-slope) are preferred. Linear-motion screens are used for dewatering and for heavy-duty sizing at low speed.
Q: How do I prevent screen blinding and pegging? A: Use appropriate screen media (rubber, polyurethane, self-cleaning wire mesh) for the application. Maintain adequate feed rate and material bed depth. Apply spray water for sticky materials. Keep screen panels properly tensioned.
Q: How do I size a belt conveyor? A: Belt conveyor sizing depends on tonnage, material bulk density, lump size, belt speed, conveyor length, lift height and idler spacing. WSHT provides conveyor sizing as part of our crushing and screening plant design service.
About Grinding Mills
Q: What is the difference between a ball mill and a SAG mill? A: A ball mill uses steel balls as grinding media inside a rotating cylindrical shell to grind ore to fine size. A SAG (Semi-Autogenous Grinding) mill uses the ore itself as grinding media together with a smaller charge of steel balls; it is used for primary grinding of coarse feed. An AG (Autogenous Grinding) mill uses only ore as grinding media.
Q: What grind size do I need? A: The required grind size depends on the mineral liberation characteristics of the ore and on the requirements of the downstream beneficiation process. Typical P80 grind sizes range from 75 microns (fine grind for flotation) to several hundred microns for gravity-only gold circuits. Ore testwork determines the optimal grind size.
Q: What is the role of hydrocyclones in a grinding circuit? A: Hydrocyclones classify ground ore by particle size, returning oversize particles to the grinding mill for further size reduction while allowing correctly-sized particles to report to downstream beneficiation. Hydrocyclones are the dominant classification device in modern grinding circuits.
About Spare Parts, Maintenance and Delivery
Q: What spare parts should I keep on-site? A: WSHT recommends keeping fast-moving wear parts (jaw plates, cone liners, blow bars, screen media, belts, bearings, seals) and critical insurance spares (gearbox components, hydraulic cylinders, motors) on-site. Our recommended spare parts lists are customized to each specific equipment package.
Q: What is the typical delivery time for a crushing plant? A: Small single-crusher packages typically ship within weeks. Large multi-machine EPC projects require multiple months for engineering, manufacturing, shipping and on-site installation and commissioning.
Q: Does WSHT provide operator training? A: Yes — WSHT provides operator training, maintenance training and commissioning supervision as part of every major equipment supply and EPC project. We also deliver ongoing technical support and spare parts supply after commissioning.
