Custom CNC Machined Plastic Bellows
Precision machined flexible bellows and expansion joints from solid plastic stock for piping systems, equipment protection, and shaft sealing applications
- Complete bellows CNC machined from solid stock - no molding tooling required
- Custom convolution counts, diameters, and wall thickness to your specifications
- PTFE, PEEK, nylon, and acetal materials for chemical resistance and flexibility
- Applications: expansion joints, pulse dampeners, shaft seals, protective covers
- Reverse engineering service for obsolete bellows replacement
Overview
CNC machined flexible plastic bellows for industrial piping, equipment protection, and motion systems.
CDS Plastics manufactures complete flexible bellows entirely through CNC machining from solid plastic stock. Unlike molded bellows requiring expensive tooling, our machined bellows accommodate custom dimensions, convolution patterns, and specialized materials without tooling investment. We machine thin-walled accordion structures that provide flexibility for expansion joints, vibration absorption, and motion compensation in piping systems, pump connections, and equipment protection applications. Our precision machining capabilities produce bellows from PTFE, PEEK, and other engineered plastics offering superior chemical resistance and temperature performance compared to rubber alternatives.
Why Choose CDS Plastics CNC Machined Bellows
No Tooling Investment Required
CNC machining eliminates expensive mold tooling costs that make custom molded bellows economically unfeasible. Design changes accommodated easily without tooling modifications or delays.
Superior Chemical Resistance
PTFE and PEEK machined bellows withstand aggressive chemicals, acids, bases, and solvents that attack rubber and molded plastic alternatives. No degradation, swelling, or permeation in harsh environments.
Custom Specifications
Every bellows machined to exact convolution count, diameter, wall thickness, and length requirements. Accommodate non-standard pipe sizes and unique mounting configurations without compromise.
Enhanced Durability
Machining from solid stock creates stronger, more consistent wall thickness compared to molding. No weak points from parting lines or gate marks that cause premature failure.
Solutions for Common Bellows Challenges
Chemical Attack on Standard Bellows
Non-Standard Dimensions Required
Obsolete Equipment Parts Unavailable
High Temperature Degradation
Premature Failure from Inconsistent Wall Thickness
Technical Specifications & Capabilities
Machining Capabilities
- Inside diameter: 0.5" through 12"
- Convolution count: 1 through 20+ folds
- Wall thickness: 0.030" through 0.250"
- Length: Compressed and extended dimensions custom
- Flange options: Integral or separate mounting
- Tolerance: ±0.005" on critical dimensions
Common Applications
- Piping expansion joints for thermal movement
- Pump flexible connectors for vibration isolation
- Shaft seals for rotating equipment
- Pulse dampeners for reciprocating pumps
- Protective covers for linear actuators
- Vacuum chamber flexible connections
Material Selection Guide for Machined Bellows
| Material | Flexibility & Strength | Chemical & Temperature | Best Applications |
|---|---|---|---|
| PTFE (Teflon®) | Good flexibility, moderate strength | Universal chemical resistance, -400°F to 500°F | Aggressive chemicals, high purity, wide temperature range |
| PEEK | Excellent strength, good flexibility | Outstanding chemical resistance, up to 480°F continuous | High temperature, aggressive chemicals, steam service |
| Nylon 6/6 | Very flexible, high tensile strength | Good chemical resistance, -40°F to 250°F | General purpose, wear resistance, economical |
| Acetal (Delrin®) | Good flexibility, dimensional stability | Moderate chemicals, -40°F to 180°F | Precision dimensions, clean environments |
| Polypropylene | Excellent flexibility, fatigue resistant | Very good chemical resistance, -20°F to 180°F | Cost-effective, acids and bases, cycling applications |
| PVDF (Kynar®) | Good flexibility, high strength | Excellent chemical resistance, -40°F to 280°F | Strong acids/bases, outdoor UV exposure, chlorinated systems |
| UHMW-PE | Very flexible, abrasion resistant | Good chemical resistance, -260°F to 180°F | Sliding applications, noise dampening, low temperature |
Information We Need From You
To machine your custom bellows, provide us with:
- Inside and outside diameters
- Number of convolutions required
- Compressed and extended lengths
- Wall thickness requirements
- Flange or mounting details
- Fluid/gas type for material selection
- Operating temperature and pressure
- Drawing or existing bellows sample
Industries and Applications
Chemical Processing
- Piping expansion joints for corrosive chemical systems
- Pump flexible connectors for acid and solvent transfer
- Reactor vessel flexible connections for thermal expansion
- PTFE bellows withstand aggressive chemical environments
- Custom sizes for non-standard pipe configurations
Pharmaceutical Manufacturing
- Sanitary process piping flexible connections
- Clean-in-place system expansion joints
- USP Class VI compliant materials available
- Smooth machined surfaces prevent bacterial growth
- PEEK bellows for high-temperature sterilization
Water & Wastewater Treatment
- Chlorine-resistant bellows for chemical feed systems
- Pump vibration isolators for piping protection
- Expansion joints for large diameter pipe systems
- CPVC and PVDF materials resist chlorine degradation
- Custom flanges match municipal pipe standards
Semiconductor & Vacuum Systems
- Ultra-high vacuum flexible connections
- Cleanroom-compatible materials prevent contamination
- Outgassing-resistant plastics for vacuum applications
- Precise dimensions maintain seal integrity
- Corrosive gas handling in plasma etching systems
Industrial Machinery
- Reciprocating pump pulse dampeners
- Hydraulic system flexible connections
- Linear actuator protective boots and covers
- Rotating shaft seals for equipment protection
- Vibration isolation for sensitive equipment
Food & Beverage Processing
- FDA-compliant bellows for sanitary piping
- Pump connectors for product transfer systems
- Washdown-resistant materials for daily cleaning
- Expansion joints for hot water and steam lines
- Non-contaminating plastics prevent taste/odor transfer
Ordering Process
We manufacture custom machined bellows from your specifications and drawings.
Information Required for Quoting
- Technical drawing with dimensions
- Material requirements based on your application
- Operating conditions: temperature, pressure, chemical exposure
- Quantity needed and delivery requirements
- Existing bellows for reverse engineering (if applicable)
Common Bellows Specifications
- Convolution count and depth
- Wall thickness requirements
- Material type based on chemical exposure
- End configurations: flanged, threaded, or plain
- Mounting hardware: integral or separate flanges
- Pressure and temperature ratings
Reverse Engineering Service Available
Send us your existing bellows for complete dimensional analysis. We'll capture all specifications and manufacture exact replacements with documentation for future reorders.
Frequently Asked Questions
How are CNC machined bellows different from molded bellows?
CNC machined bellows are created by machining thin-walled accordion structures from solid plastic stock. This eliminates expensive mold tooling costs and allows complete customization of dimensions, convolution patterns, and materials. Machining creates stronger, more consistent wall thickness without weak points from mold parting lines. Unlike molded bellows requiring minimum order quantities to justify tooling, we machine single prototypes through production quantities economically.
What's the minimum quantity for custom machined bellows?
We machine single prototype bellows through production quantities. CNC machining requires no tooling investment, making custom bellows economical for any quantity. Most orders range from single replacements to several hundred pieces depending on application requirements and lead time needs.
How do I select the right material for my bellows application?
Material selection depends primarily on chemical exposure and operating temperature. PTFE offers the broadest chemical resistance for aggressive environments. PEEK provides high-temperature capability to 480°F continuous. Nylon and polypropylene offer economical solutions for general applications. Our team can help you select the appropriate material based on your specific fluid chemistry, temperature range, and pressure requirements.
