Machining and welding PVC-CAW

PVC-CAW is a rigid PVC (unplasticised PVC, PVC-U) – an amorphous engineering thermoplastic valued above all for its excellent chemical resistance and its flame-retardant behaviour (UL 94 V-0, DIN 4102 B1). The grey-coloured material is stiff, strong and economical and is the standard material for chemical apparatus and tank construction, electroplating and ventilation. Its service temperature is limited to about 0 to +60 °C.

PVC-CAW machines well – sawing, milling, turning and drilling give clean, dimensionally accurate results; we use sharp tools and keep the cutting zone cool to avoid thermal decomposition. We also offer cold-bending, thermoforming and plastic welding – this is how we produce chemically resistant tank, apparatus and structural parts from single pieces to series production.

PVC-CAW is worthwhile whenever chemical resistance and fire protection must be combined economically – for example:

• Chemical apparatus, tank and pipework construction
• Electroplating and pickling plants, surface technology
• Ventilation and exhaust-air ducts (flame-retardant)
• Water treatment and waste-water technology
• Insulating and structural parts with fire-protection requirements

PVC-CAW is one of the most economical engineering plastics and is priced well below high-performance and fluoropolymers. The part price is mainly determined by semi-finished shape (sheet, rod, tube), dimension, material utilisation (offcut), machining or welding effort and lot size. We are happy to quote binding prices on request based on your drawing.

Equally important are the limits of the material:

• Food or drinking-water contact (technical grade, not approved)
• Continuous use above about 60 °C (the material softens)
• Use below 0 °C or high impact loading (PVC-U is brittle)
• Contact with solvents such as esters, ketones, chlorinated hydrocarbons (swelling/attack)
• Applications with high continuous temperature – then PVDF, PP or PE

An honest assessment – and how the disadvantages can be mitigated in practice: Advantages:

Disadvantages:

Practical tip: PVC-CAW is the right choice when chemical resistance, weldability and fire protection are required economically – for example in tank and apparatus construction or electroplating. If higher temperatures, drinking-water/food contact or high impact strength are required, PP, PE-HD or PVDF are the better choice.

• Very good chemical resistance (acids, alkalis, salts)
• Flame-retardant and self-extinguishing (UL 94 V-0, DIN 4102 B1)
• High rigidity and strength
• Readily weldable and thermoformable (tank construction)
• Economical and widely available
• Not for food/drinking-water contact (technical grade)
• Limited service temperature (0 … +60 °C)
• Brittleness / low impact strength, especially in the cold
• Sensitive to certain solvents (esters, ketones)
• HCl formation on overheating/fire