O-rings & seals
FFKM and AS568 O-rings, valve seal kits and compound selection for semiconductor tools.
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O-ring failure modes in semiconductor tools: read the failed seal, then choose the elastomer by chemistry and temperature
**Short answer:** Before you reorder a failed O-ring, look at it in cross section. A ring with flat sides and no rebound has taken a compression set. Material squeezed into the clearance gap means extrusion. An oversized, soft ring has swel
AS568 O-ring sizes in 5 minutes: dash-number series, squeeze worked example and FKM vs FFKM choice
**Short answer:** An AS568 dash number fixes the inside diameter and the cross section, and the first digit gives the cross-section series. Material and hardness are specified separately. Size the ring from the groove, check the squeeze, th
Selecting FFKM AS568 O-rings for semiconductor tools: FFKM vs FKM vs EPDM, grade by process and RFQ checklist
**Short answer:** Use FFKM where a seal sees fluorine or oxygen plasma, temperatures above the roughly 204 °C limit of FKM, or chemicals that FKM does not tolerate, such as amines and ammonia. Choose the FFKM grade by process step, not just
AS568 dash numbers for FFKM O-rings: reading cross-section families, the three "25 mm" rings, and the Kalrez shrinkage note
**Short answer:** An AS568 dash number fixes both the inside diameter (ID) and the cross-section (CS) of an O-ring. In the DuPont Kalrez AS-568 dimensions table, sizes -004 to -050 are 1.78 mm (.070 in) cross-section and the -1xx sizes are
How to write an FFKM O-ring RFQ that actually gets quoted (size, compound, process, chemistry, quantity)
**Short answer:** An O-ring request that says only "Kalrez O-ring, 25 mm" cannot be quoted. A supplier needs two separate things: the **size** (an AS568 dash number, an ISO 3601 / JIS size, or ID × cross-section with tolerances) and the **c
VAT pendulum valve seal kits: finding the right part number in the 650/655 manuals
**Short answer:** VAT ties spare parts to the valve's **fabrication number** (on the label). Its manuals say to quote that number when ordering, because the ordering number alone doesn't pin down seal material or variant. In the Series 650
Kalrez 9100 vs 9300 vs 9500 vs 9600: reading DuPont's semiconductor selector guides before an FFKM RFQ
**Short answer:** DuPont splits its semiconductor Kalrez recommendations across three 4-page selector guides: Plasma (KZE-A40111), Thermal (KZE-A40112) and Wet (KZE-A40110). In the plasma guide, 9100/9500 are listed for HDPCVD, 9600 for PEC