Industrial Valve Reference
Valves for Catch Pots, Vacuum Systems & Chemical Process Industries
A complete technical guide to valve materials, seat options, application selection, and recommended arrangements for chemical, pharmaceutical, solvent, and vacuum process systems.
The selection of valve material is critical because it directly affects corrosion resistance, vacuum integrity, service life, safety, and maintenance costs. Choosing the wrong material leads to accelerated wear, process contamination, and costly downtime.
Valve Materials
10 primary materials used across chemical and vacuum process industries
1
Stainless Steel (SS) Valves
Grades
- SS 304 / 304L
- SS 316 / 316L
- Duplex SS & Super Duplex SS
Operating Range
−50°C to 550°C
Vacuum to 100+ Bar
Advantages
- Excellent corrosion resistance
- Long service life
- Suitable for vacuum service
- Easy maintenance
Common Types
Applications
- Chemical & pharmaceutical plants
- Food processing
- Solvent handling & vacuum systems
2
PTFE-Lined Valves
Construction
- Carbon Steel Body + PTFE Lining
- Stainless Steel Body + PTFE Lining
Operating Range
−20°C to 200°C
Advantages
- Excellent chemical resistance
- Low friction, non-stick surface
- Suitable for aggressive chemicals
Typical Chemicals
3
PFA-Lined Valves
About PFA
- Perfluoroalkoxy Alkane (PFA)
- Superior grade lining vs PTFE
Advantages Over PTFE
- Better flexibility
- Better permeability resistance
- Improved lining quality
Applications
- Ultra-pure chemicals
- Pharmaceutical plants
- High-purity process systems
4
Polypropylene (PP) Valves
Operating Range
Up to 90°C
Advantages
- Lightweight construction
- Low cost
- Good corrosion resistance
Applications
- Acid transfer lines
- Water treatment systems
- Chemical dosing
5
PVDF Valves
Material
- Polyvinylidene Fluoride (PVDF)
Operating Range
Up to 140°C
Advantages
- Better strength than PP
- Excellent chemical resistance
- UV resistant
Applications
- Strong acids & chlorine systems
- High-purity chemical plants
6
Cast Iron (CI) Valves
Advantages
- Economical
- Easy availability
Limitations
- Not suitable for corrosive chemicals
Applications
- Water systems
- Utility services
7
Carbon Steel (CS) Valves
Grades
- ASTM A216 WCB
- ASTM A105
Advantages
- Strong construction
- Cost effective
Applications
- Steam service
- Oil systems
- Utility services
8
Hastelloy Valves
Grades
- Hastelloy C276
- Hastelloy B2
Advantages
- Exceptional corrosion resistance
Typical Chemicals
Applications
- Highly corrosive chemical service
- Acid plants
9
Monel Valves
Advantages
- Excellent seawater resistance
Applications
- Marine service
- Chlorine plants
- Alkali plants
10
Titanium Valves
Advantages
- Outstanding corrosion resistance
- Lightweight construction
Applications
- Chlorine service
- Seawater systems
- Specialty chemical plants
Valve Seat Materials
Temperature ratings and applications for common seat and seal materials
| Material | Temperature Range | Applications |
|---|---|---|
| PTFE | Up to 200°C | Chemicals, Vacuum |
| RPTFE | Up to 230°C | Higher strength applications |
| PEEK | Up to 250°C | High-performance service |
| Viton | Up to 200°C | Solvents |
| EPDM | Up to 150°C | Water, acids |
| Nitrile (NBR) | Up to 100°C | Oils |
| Metal Seat | Up to 600°C | Steam, high temperature service |
Valve Selection for Catch Pot Applications
Service-specific material recommendations for process engineers
| Service | Recommended Valve Material |
|---|---|
| Vacuum Catch Pot Drain | SS316 Ball Valve |
| Solvent Recovery | SS316 / PTFE-Lined Valve |
| Acid Service | PTFE / PFA-Lined Valve |
| HCl Service | PTFE-Lined or Hastelloy |
| Sulfuric Acid | PTFE-Lined Valve |
| Pharmaceutical Plant | SS316L Ball Valve |
| High Temperature Service | SS316 or Metal-Seated Valve |
| Chlorine Service | PTFE-Lined, PVDF, Titanium |
| Caustic Service | SS316 / PTFE-Lined Valve |
Typical Valve Arrangement on a Catch Pot
Standard connection locations and valve types by position
▲ Top Connections
- Vacuum Isolation Ball Valve
- Vacuum Relief Valve
- Vent Valve
◀▶ Side Connections
- Pressure / Vacuum Gauge Valve
- Sample Valve
- Level Indicator Isolation Valve
▼ Bottom Connections
- Drain Ball Valve
- Flush Valve
- Condensate Discharge Valve
⚠ Safety Connections
- Safety Relief Valve (SRV)
- Rupture Disc
Recommended MOC for Chemical & Vacuum Applications
Component-level material specification for standard installations
| Component | Preferred Material |
|---|---|
| Catch Pot Body | SS316L |
| Demister Pad | SS316 |
| Drain Valve | SS316 Ball Valve |
| Vacuum Isolation Valve | SS316 Ball Valve |
| Gasket | PTFE |
| O-Ring | Viton / PTFE |
| Sight Glass Seal | PTFE |
| Safety Valve | SS316 |
Best-Practice Material Combination
For most chemical, pharmaceutical, solvent recovery, and vacuum pump protection systems, SS316L construction with PTFE gaskets/seats and SS316 ball valves provides the best balance of corrosion resistance, vacuum performance, durability, and cost.
Body
SS316L
Gaskets
PTFE
Valves
SS316 Ball
O-Rings
Viton / PTFE