Kalrez® Compound Selector & In‑Stock Guide: 4079 vs 6375 vs 6230 vs 3018 (and more)

Choosing the right Kalrez® compound is one of the fastest ways to improve uptime and reduce leaks in aggressive or high‑temperature applications. Different compounds are optimized for different fluids, temperatures, and compliance needs. The challenge is that availability and lead times can vary, and some projects also need rapid documentation support or cleanroom packaging. That is where Canyon Components helps. We stock and source popular Kalrez O‑ring sizes, provide application guidance, and offer Canrez perfluoroelastomers as high‑value alternatives when you want equal performance with a faster delivery or lower total cost.

This guide explains how to select compounds, summarizes the most used Kalrez families, and shows you how to map each choice to a Canrez option. You will also find quick pointers on groove design, extrusion control, and compliance so your selection is robust in the field.

Useful references as you read:

• Kalrez perfluoroelastomers
• Canrez perfluoroelastomers
• High‑temperature elastomers
• Oil and gas industry
• API 6A materials, NORSOK M‑710 materials, NACE TM0297 materials
• O‑ring groove design guide, Backup rings
• Cleanroom manufacturing and packaging, Material testing and part identification, Reverse engineering services
• Chemical compatibility guide
• Spring‑energized seals
• External lubrication

How to choose: the three variables that decide your compound

Before you pick a compound, list these items and keep them in front of you:

1. Media and environment. Chemical contact, hydrocarbons, organic acids, amines, oxidizers, steam or hot water, plasma or vacuum. The fluid and the cleaning chemistry matter as much as the process media. When in doubt, skim Canyon’s chemical compatibility guide for a directional check, then ask our team to confirm at temperature.
2. Temperature and pressure profile. Continuous temperature and realistic excursions. Pressure level and whether pressure cycles. If pressure is high, plan for extrusion control with backup rings.
3. Compliance or cleanliness requirements. Food and pharma may call for FDA or USP Class VI. Oil and gas often reference API 6A, NORSOK M‑710, or NACE TM0297. Semiconductor tools care about outgassing, particles, and plasma resistance. Canyon can package, label, and document to your program using cleanroom manufacturing and test reports.

Quick Kalrez® selector: short phrases to narrow the field

Tables should be easy to scan. Use this as a starting point, then read the mini‑profiles that follow. The last column provides a natural pivot to Canrez when you want equal performance with better availability or value.

Mini‑profiles and selection notes

These brief summaries help you understand why each group exists and when to pivot to Canrez.

High‑temperature general purpose: 4079 and 7075

These are the classic picks when you need strong heat resistance and broad chemical coverage. 4079 is the well‑known generalist. 7075 emphasizes lower compression set and stability in thermal cycling. If you need improved performance, if lead time is critical or you want a more favorable price, request Canrez CP75BK01 or Canrez CP75BK20. You get the same high‑heat envelope with a simple switch in part number and documentation.

High‑hardness and extrusion control: 7090

When pressure is high and clearances are imperfect, hardness and modulus can reduce nibbling and extrusion. 7090 is a 90A grade that holds shape under load. Verify groove dimensions, because drift toward high hardness in a tight groove can raise assembly loads. If 7090 is long lead, a Canrez 90A alternative CP90BK01 can hold the same line while you control TCO. Add backup rings where gaps are variable.

Broad chemical windows: 6375

Plants with mixed media often choose 6375 to cover acids, bases, solvents, and process cleaners. Confirm the specific bases and amines present, then compare against a Canrez broad‑chem grade, CP75BK03. If you need to combine steam plus mixed chemistry, consider moving toward the steam segment below or to a hybrid seal approach.

Steam and hot water: 7375, 7390, and 3018

Steam requires a steam‑tuned network. 7375 is the typical starting point for pressurized hot water and steam. 7390 adds 90A hardness for extrusion resistance and loaded dynamics. 3018 is a proven 90A steam specialist that many maintenance teams prefer in utilities. When steam and cost or availability collide, ask for a Canrez steam‑rated FFKM like CP75BK01 and CP90BK01. You keep the steam performance while improving delivery and budget. Also review groove fill and corner radii using the groove design guide.

Amines and strong bases: 6380

Amines are a known challenge at temperature. 6380 is aimed at these environments. If you need to combine amines with pressure cycling or seam into AED work, ask for a Canrez amine grade like CP75Bk03.

Low‑temperature specialty: 0040

For cold environments that still demand FFKM purity and chemical resistance, 0040 is a logical choice. When low temperature and budget are both priorities, a Canrez low‑temp FFKM like CP75BK91 can be the faster option. For deep cryogenic or vacuum duty where even FFKM can struggle to maintain force, consider spring‑energized seals.

RGD or AED service: 0090

Rapid gas decompression risk needs to be taken seriously in gas systems. 0090 is designed for RGD or AED duty. Real results depend on the decompression rate and the exposure history, so plan a pressure ramp and verify against NACE TM0297 materials. When you need an RGD grade fast, a Canrez AED option like CP90BK91 is a practical path.

Food and pharma compliance: 6221 and 6230

Where certifications such as FDA or USP Class VI matter, these compounds give you a clean paper trail. If your plant runs steam sterilization or CIP and you need a more flexible sourcing plan, a Canrez compliant grade like CP75WH18 or CP75BK02 plus cleanroom manufacturing and packaging keeps audits simple.

Semiconductor clean and plasma: 8575

Semiconductor tools require ultra‑low outgassing, low particles, and in some steps plasma‑resistant properties. 8575 is tuned for plasma and ash. If you need a faster or more economical option without sacrificing cleanliness, evaluate Canrez clean and plasma grades like CP80WH01, and ask about Canyon’s lot traceability, bag‑in‑bag packaging, and clean build documentation.

In‑stock and quick‑ship: how to move faster

Project timing often beats theory. When you need parts quickly, ask us to check stock for both the Kalrez compound and the nearest Canrez cross‑reference. Because Canrez is in Canyon’s core portfolio, we can often ship faster, match performance, and package to your specification using cleanroom manufacturing and packaging. If you are replacing a competitor part or have only a sample, our material testing and part identification and reverse engineering services can create a clean cross‑reference with documentation.

Design guidance that prevents failures after you choose the compound

• Verify squeeze and gland fill using the O‑ring groove design guide. Confirm both the cold start and hot soak condition so squeeze does not fall out of range as temperatures change.
• Control extrusion with backup rings. This is especially important for steam, amines, and gas service where pressure pulses and temperature swings soften the seal.
• Plan decompression in gas duty. Even RGD‑rated compounds need a realistic pressure ramp and dwell. Reference NORSOK M‑710 materials and NACE TM0297 materials.
• Use compatible lubricants for installation and dynamic duty. If you need guidance, review external lubrication.
• Document compliance and cleanliness up front. If your application requires FDA, USP, or a clean packaging regime, lock those requirements into your RFQ and use Canyon’s cleanroom manufacturing and packaging to reduce approval friction.

The Canrez advantage: the smarter alternative

• Performance parity where it counts. Canrez covers the same high‑temperature, aggressive chemistry, and compliance envelopes you buy Kalrez to handle. When your process window matches, you can keep performance and shorten delivery.
• Lead time and availability. A second qualified option helps you meet outage windows and project milestones. Canrez is often the faster path to the same uptime goal.
• Total cost of ownership. Lower part cost is one piece. The bigger lever is reduced downtime when you can actually get parts on site. If you carry inventory, the ability to stock Canrez for standard sizes makes planning simpler.
• Packaging, testing, and documentation in one place. If you also need clean packaging, material verification, or a certificate bundle, Canyon programs those into your order.
• Step‑up options when seals are still failing. Combine Canrez with spring‑energized seals in the highest risk interfaces, or pair the seal with backup rings and minor groove changes.

Selector flow: a simple path from application to part number

• Steam/hot water: Kalrez® 7375, 7390, 3018 — or use Canrez CP75BK01 / CP90BK01 steam-rated FFKM for equivalent performance with faster delivery and lower cost.
• Amines: Kalrez® 6380 — or Canrez CP75BK03 for amine resistance with better availability.
• Oxidizers/reactive: Kalrez® 7275 — or a Canrez oxidizer grade to simplify sourcing.
• RGD/AED gas duty: Kalrez® 0090 — or Canrez CP90BK91 AED FFKM for oil & gas decompression resistance.
• Broad chem at heat: Kalrez® 6375 or 4079 (7075 for lower set) — or Canrez CP75BK03 (broad-chem) and CP75BK01/20 (general purpose) for high-temp cycles.
• Semiconductor clean/plasma: Kalrez® 8002/8575 — or Canrez CP80WH01 (clean plasma) for lower outgassing and controlled packaging.
• Food/pharma: Kalrez® 6221/6230 — or Canrez CP75WH18 and CP75BK02 for FDA/USP VI compliance with cleanroom packaging.
• Cold + chemicals: Kalrez® 0040 — or Canrez CP75BK91 low-temp FFKM for cryogenic service, or escalate to spring-energized PTFE for extreme duty.

Check hardness, motion, and extrusion risk.
If pressure is high or motion is dynamic, verify fit of 90A grades such as Kalrez® 7090/7390 — or Canrez CP90BK01 — and add backup rings where extrusion gaps are variable.

Ask for Canrez and in‑stock options. Once the compound and hardness are set, ask us to quote the Kalrez part and the nearest Canrez alternative side by side. If you have a shutdown date, we will prioritize in‑stock sizes and the documents you need.

When to consider spring‑energized PTFE instead of FFKM

If you are at the edges of temperature, vacuum, or cleanliness, a spring‑energized PTFE seal can outperform elastomers by maintaining contact force through cold starts and hot soaks, resisting extrusion at pressure, and eliminating outgassing concerns. The tradeoff is different friction and more precise hardware. When your process is truly extreme, review spring‑energized seals with Canyon engineering and keep FFKM for secondary interfaces.

Ready to choose and buy

Whether you need a specific Kalrez compound by name or want to open the door to a faster and more economical outcome with Canrez, Canyon Components will get you there. Start with the selector above, then send your media list, temperature and pressure profile, and any compliance notes. We will return a precise Kalrez recommendation, a Canrez cross‑reference, and an in‑stock path that fits your schedule.