Rotary shaft seals for Metal & Aggregate.
Metal and aggregate processing handles the hardest, most abrasive solids in industrial service: frac sand at 7 Mohs, alumina at 9 Mohs, slag and silicon carbide at the upper limit of what any seal will tolerate. The seal answer here is tungsten faces, hardened housings, and a generous air purge.
01The challenge
Why sealing this service is hard.
These are the failure modes our application engineers have catalogued from twenty-five years of metal & aggregate installations. Most are visible only after a seal has been pulled.
- 01
Surface speeds that destroy soft faces
Even at moderate RPM, a high-density abrasive at the seal face is a grinding-wheel analog. Tungsten carbide on tungsten carbide faces are mandatory; carbon-graphite faces fail in days.
- 02
Shaft scoring under conventional packing
Compression packing on a frac-sand or alumina screw shaft scores the shaft inside one shift. The 7500-AB is non-contact at the shaft — there's nothing to score.
- 03
Static buildup and dust explosion risk
Dry powder transfer at high velocity generates static. ATEX zone-rated air purge regulators and conductive housings keep the system intrinsically safe.
- 04
High-pressure pneumatic transfer
Dense-phase pneumatic transfer of frac sand or proppant runs at 30 to 60 psig. The 9700-WC is rated for the pressure and the abrasion together — most rotary seals only handle one.
02Recommended series
What we ship for metal & aggregate.
03Common equipment
Where we typically install in metal & aggregate plants.
04Compliance & materials
Documentation we ship with the seal.
- Tungsten / tungsten and silicon-carbide / tungsten face combinations
- ATEX zone 22 dust-rated configurations on hazardous-area variants
- Hardened 17-4 PH stainless internal components
- Pressure-test certificates to 75 psig on every 9700 unit
05Engineering FAQ
What plant engineers ask before specifying.
Metal & Aggregate · sized in 24 hours
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