Specifications
| Parameter | Specification |
|---|---|
| Material | ASTM A128 Hadfield high manganese steel (11-14 percent Mn); ASTM A216 WCB optional for light duty |
| Process | Water glass lost wax or sand assisted investment casting, then CNC machining of seat face and bore |
| Tolerance | ISO 8062 CT8 as-cast; ISO 2768-m on machined features; pocket radius held to 0.30 mm |
| Surface finish | Ra 3.2 micrometres on machined seat face, Ra 12.5 elsewhere; manganese phosphate or as-cast |
| Weight range | 8 kg to 120 kg per seat block |
| Heat treatment | Solution anneal and water quench (water toughening) at 1050-1100 C; ASTM A128 compliant |
| Inspection | CMM dimensional report, Brinell hardness 190-230 HB as toughened, dye penetrant, UT on heavy sections |
Key features
- High manganese austenitic structure work hardens in service, so the toggle seat pocket surface gains hardness exactly where the toggle plate rocks against it.
- Water toughening at 1050-1100 C with rapid quench dissolves carbides and delivers the specified 190-230 HB starting hardness with full austenitic toughness.
- Machined seat pocket radius matched to the toggle plate end radius, spreading contact load and preventing edge loading that initiates frame cracking.
- Heavy section design with cast-in coring keeps weight down while preserving stiffness around the toggle thrust line.
- Dowel hole and bolt pattern machined in one setup so the block relocates to the same position after every liner change.
- Dye penetrant inspection of all machined surfaces after water toughening confirms freedom from quench related surface cracking.
- Compatible with both single toggle and double toggle jaw crusher seat geometries, with tooling adapted to the frame drawing.
Applications
- Toggle plate seat blocks for single toggle jaw crushers in aggregate and mining duty.
- Front and rear toggle seats for double toggle jaw crusher frames.
- Toggle seat blocks in primary crushing stations at quarry and mine sites.
- Replacement seat blocks for cone crusher and gyratory crusher toggle arrangements.
- Crusher frame repair programs where worn seat pockets are rebuilt with a replaceable cast block.
- Mobile and tracked jaw crusher toggle seat retrofits.
Quality & compliance
All seat blocks are manufactured under our IATF 16949 certified process control system, with melt chemistry, pouring temperature and water toughening parameters recorded per batch. PPAP documentation is prepared at the level requested, supporting crusher OEM and aftermarket programs with process flow, control plan and inspection evidence. Material certification to EN 10204 3.1 or ASTM standards confirms the manganese and carbon content that governs work hardening response, and heat treatment charts record full solution anneal and quench cycles. Full dimensional reporting covers pocket radius, seat face flatness and dowel hole position from our CMM. Non-destructive testing options include dye penetrant inspection to ASTM E165, magnetic particle inspection where applicable, and ultrasonic testing on heavy section castings to confirm internal soundness. Every block carries heat lot marking that links it to its chemistry, furnace charge and inspection records.
FAQ
Q1. Why use high manganese steel instead of a hardened alloy steel for the seat block?
ASTM A128 Hadfield steel starts tough at around 200 HB and work hardens under the repeated rocking contact of the toggle plate, building a hard surface layer while the core stays tough. A hardened alloy steel is harder initially but more prone to cracking under shock.
Q2. Can you machine high manganese steel after water toughening?
We rough machine before water toughening and finish machine the seat face and holes afterwards using carbide tooling and controlled parameters, because the work hardening rate makes aggressive post-treat machining difficult.
Q3. Do you supply the matching toggle plate?
Our scope is the cast and machined seat block. Where customers want a matched set we can coordinate with qualified toggle plate suppliers or review toggle plate drawings to confirm contact geometry compatibility.
Q4. How is the seat block secured to the crusher frame?
Typically by a machined dowel and bolt arrangement into the frame cross member, or by a pocket that captures the block against the toggle thrust. We machine whichever fixing scheme your frame drawing specifies.
Q5. What is the expected service life?
Life depends on crusher size, feed hardness and duty cycle, but a correctly heat treated manganese seat block usually outlasts several sets of toggle plates. We can review your wear pattern photographs to suggest geometry changes that extend interval.
Q6. Can you reproduce a seat block from a worn sample?
Yes, though we prefer the original drawing. If only a worn sample is available, we scan it, restore the worn pocket profile to its nominal radius with your input, and issue a drawing for approval before tooling.
