A wear plate is a wear-resistant steel or composite plate used to protect surfaces that wear quickly through abrasion, impact and sliding. In mining and crushing and screening plants, bins, chutes, troughs, crusher housings, feeder hoppers, truck bodies and buckets wear because of rock constantly flowing over or striking them. Wear plates protect these surfaces, extending the life of the main structure and making maintenance easier: the worn plate is replaced and the expensive structure is protected.
In this guide we cover in detail the types of wear plate, hardness grades, selection criteria by application, mounting, cutting and welding practice, and uses in mining.
Types of Wear Plate
| Type | Characteristics | Suitable application |
|---|---|---|
| Wear steels (quenched and tempered) | High hardness and good toughness; can be cut, bent and welded | Truck bodies, buckets, bins, chutes |
| Chromium carbide overlay plates (hardfacing) | A very hard carbide layer on a steel base | Heavy sliding wear, fine abrasive material |
| Manganese steel plates | Surface hardens under impact | High-impact areas |
| Cast liners (high chrome, Ni-hard etc.) | Very high wear resistance | Mill and pump liners, sliding wear areas |
| Ceramic liners | Very hard; low impact tolerance | Hydrocyclones, fine material chutes |
| Rubber and polyurethane liners | Impact damping, noise reduction, good performance with wet material | Chutes, screen feed boxes, troughs |
| Composite liners (rubber + ceramic) | Balance of impact and wear resistance | Transfer points |
Hardness Grades
Wear steels are usually classified by Brinell hardness (HB). Common grades are 400 HB, 450 HB and 500 HB; steels of higher hardness are also available for special applications. Products known by trade names such as Hardox® are also chosen according to this classification.
| Hardness | Characteristics | Typical use |
|---|---|---|
| 400 HB | Good toughness, easy forming and welding | General applications with impact and wear together, bent parts |
| 450 HB | Balance of wear resistance and toughness | Truck bodies, chutes, bins |
| 500 HB | High wear resistance, harder to form | Areas with heavy sliding wear |
| Higher grades | Very high wear resistance, low formability | Special wear areas |
General rule: As hardness increases, wear resistance increases; however, bending, cutting and welding become harder and sensitivity to impact may increase. Selection should be made according to the type of wear.
Selection by Type of Wear
| Type of wear | Example | Recommended plate |
|---|---|---|
| Sliding wear (fine, abrasive material) | Sand chutes, screen undersize troughs | Chromium carbide overlay, 500 HB, ceramic or polyurethane |
| Impact (large rock, high drop) | Truck dump bins, crusher feed hoppers | 400–450 HB wear steel, rubber, manganese |
| Impact + sliding | Transfer points, chutes | 450 HB, composite liners, rock box design |
| Wet and sticky material | Washing plant troughs | Rubber, polyurethane, low-friction liners |
Rock Box Design
At points where large rock falls from a height, a rock box design can be used instead of wear plate. In this design, falling material collects on a ledge and forms its own bed; incoming rock strikes this bed of material rather than the plate. Wear is thus greatly reduced. For bin and chute design, see our bin guide.
Mounting Methods
- With countersunk bolts: The plate is fixed with bolts that sit flush with the surface; easy to replace. For bolt selection, see our bolts and nuts guide.
- By welding: The plate is welded directly to the structure; more laborious to replace.
- Plug welding: Welding to the structure through holes cut in the plate.
- Modular liner systems: Standard-size liners that can be changed quickly with rail or pin systems.
Mounting methods that make replacement easy reduce maintenance time and safety risks.
Cutting and Welding
- Cutting: Wear steels can be cut by oxy-fuel, plasma, laser or water jet. Thick plates may need preheating before thermal cutting; the hardness of the cut edge may change.
- Welding: Follow the manufacturer’s recommended consumables, preheating and heat input limits. Excessive heat input reduces hardness in the heat-affected zone.
- Drilling: Suitable drills and cutting parameters should be used for high-hardness plates; where possible, holes should be made by thermal cutting.
- Chromium carbide plates: Never weld on the overlay side; they are fixed from the base steel side. Cutting is usually done by plasma.
Uses of Wear Plates in Mining
| Equipment | Wear area | Related guide |
|---|---|---|
| Bins and feeders | Hopper walls, feeder pan | Feeder types |
| Crushers | Housing liners, cheek plates, feed chutes | Housing liners |
| Screens | Feed box, side plates, discharge lips | Screen spare parts |
| Conveyor transfer points | Chutes, loading troughs | Skirt rubber and loading chute |
| Trucks and buckets | Body floor, bucket lips | Loading and hauling |
| Screw washers | Flight and tub liners | Screw sand washer |
Wear Monitoring and Life
The thickness of wear plates should be measured periodically (an ultrasonic thickness gauge is a practical tool), and plates should be replaced before the structure underneath is damaged. Tonnage-based life records make an economic comparison of different plate types possible. For a general comparison of wear part materials, see our crusher wear parts materials guide.
Common Mistakes
- Using the same plate everywhere; not distinguishing impact and sliding areas.
- Using a very hard plate in a high-impact area (risk of cracking).
- Ignoring preheating and heat input rules when welding.
- Waiting until the plate is completely worn and wearing the structure.
- Positioning plate joints without considering the direction of flow (joint edges wear early).
Frequently Asked Questions
What is a wear plate?
A wear-resistant steel or composite plate used to protect surfaces that wear through abrasion and impact.
Should I choose 400 HB or 500 HB?
400–450 HB is more suitable where impact dominates and forming is needed; 500 HB or overlay plates where there is heavy sliding wear.
Where is chromium carbide plate used?
It gives very long life on chute, trough and bin surfaces where fine abrasive material slides; it is not suitable for high-impact areas.
Can wear plate be welded?
Wear steels can be welded with suitable consumables and procedures; on chromium carbide overlay plates, welding is done from the base steel side.
Factors Affecting Wear Plate Prices
| Factor | Effect |
|---|---|
| Hardness grade | Steels of higher hardness are generally more expensive |
| Thickness and weight | The main determinant of plate price |
| Overlay type | Chromium carbide overlay plates cost more than plain wear steel |
| Cutting and machining | Plasma or laser cutting, holes, countersinks and bending |
| Quantity and size | Scrap rate from standard sheet sizes |
Wear plate cost should be assessed not only by plate price but together with replacement frequency, labour and downtime.
How Is Wear Plate Thickness Chosen?
- Expected wear rate (mm/month or mm/1,000 tonnes) and target replacement interval,
- Impact intensity (large rock and drop height),
- Strength of the supporting structure and weight limits,
- Mounting method (minimum thickness for countersunk bolts).
The required wear allowance is found by multiplying the measured wear rate by the target life, and a safety margin is added.
Glossary
- HB (Brinell): A unit of hardness measurement.
- Abrasion: Hard particles wearing a surface by sliding.
- Hardfacing: Depositing wear-resistant weld metal on a surface.
- Rock box: A ledge design in which the material protects itself.
- Heat-affected zone: The area whose properties change because it is heated during welding or cutting.
More Questions
Can wear plate be bent?
Wear steels in the 400–450 HB class can be bent if the manufacturer’s recommended minimum bending radii are respected; bendability decreases in harder grades.
Rubber liner or steel plate?
Rubber is preferred with fine, wet material where impact damping and noise reduction are important; steel plate with large, sharp and hot material.
Support from CSP Mühendislik
CSP Mühendislik offers fabrication, cutting and fitting of wear plates and liners for bins, chutes, troughs, crusher housings and screen feed boxes, together with service, maintenance and repair. See our bin spare parts, feeder spare parts and crusher spare parts pages.
