The Castair VA050 is a 1-1/2" NPT x 18" metal flex hose — the flexible vibration-isolation connection between your air compressor pump and the tank or discharge line. If you're replacing a flex hose on a Castair compressor, this is an OEM-spec part. The 18-inch length provides adequate slack to absorb pump vibration without putting stress on the tank fitting or hard plumbing downstream. The 1-1/2" NPT connection is sized for larger single-stage and two-stage compressors in the upper HP range of Castair's piston lineup.
Why Metal Flex Hose Matters
A metal flex hose on an air compressor is not optional equipment — it's a critical vibration isolator. Air compressor pumps vibrate significantly during operation. Without a flexible connection between the pump and tank, that vibration transmits directly into the tank fittings, manifold, and any hard-plumbed lines connected to the outlet. Over time, this causes fatigue cracking at fittings, loosens connections, and can crack check valves and tank welds at the fitting interface.
Metal flex hoses also allow for minor misalignment during installation. Compressor tanks and pump mounts are not always in perfect alignment — the flex hose accommodates that without forcing the pump outlet to bear the load.
When to Replace Your Flex Hose
- Visual inspection shows cracking, corrosion, or mechanical damage to the braided exterior
- Hose is leaking at either fitting
- Hose is kinked from a previous installation or impact
- Compressor has been running without a flex hose (direct hard connection) and you're experiencing tank fitting or check valve failures
- Hose is beyond 5-7 years of continuous shop use — metal flex hoses are wear items
Construction and Specifications
- Connection Type: 1-1/2" NPT male on both ends (standard NPT thread for compressor pump outlets and tank fittings)
- Length: 18 inches overall
- Construction: Stainless steel braided flex hose with NPT fittings — rated for compressed air service at typical compressor operating pressures
- Application: Castair compressor pump-to-tank discharge connection, vibration isolation
- OEM Part: Castair factory specification for compressors using 1-1/2" NPT discharge connections
Sizing Your Flex Hose
Castair offers metal flex hoses in multiple NPT sizes to match different compressor HP ranges and pump discharge sizes. Match the hose size to your pump's discharge port — using an undersized hose restricts airflow and creates unnecessary pressure drop; using an oversized hose requires adapters and creates leak points.
Available Configurations — Full Flex Hose Lineup
- VA075 ($59.29) — 3/4" NPT Male x 18" Metal Flex Hose — for smaller single-stage compressors
- VA100 ($99.95) — 1" NPT Male x 18" Metal Flex Hose — mid-size compressors
- VA125 ($102.49) — 1-1/4" NPT x 18" Metal Flex Hose — for 25-40 HP rotary compressors
- VA050 ($46.59) — 1-1/2" NPT x 18" Metal Flex Hose (this part) — larger piston compressors
- VA150 ($111.80) — 1-1/2" NPT Male x 18" Metal Flex Hose — larger piston compressors
- VA200 ($131.29) — 2" NPT Male x 18" Metal Flex Hose — high-capacity systems
- VA100J36 ($203.28) — 1" JIC Female/Female x 36" Metal Flex Hose — extended length, JIC fittings
Verify your pump outlet thread size before ordering. Check the pump discharge port with a thread gauge if you're unsure — NPT and BSP threads look similar but are not compatible.
What's in the Box
- 1x Castair VA050 Metal Flex Hose — 1-1/2" NPT x 18"
Technical Specifications
- Part Number: VA050
- Manufacturer: Cast Air / Castair
- Connection Size: 1-1/2" NPT
- Length: 18 inches
- Category: Ball Valves / Flex Lines — Parts
- Price: $46.59
Pressure rating and full material specifications were not available from manufacturer data at time of writing. Contact us to confirm suitability for your system's operating pressure before installation.
Why Buy From Air Compressor Factory Direct?
- Castair Parts Specialist: We stock the full Castair flex hose lineup and can confirm the right size for your specific compressor model
- Free Shipping: On qualifying orders to the contiguous US
- Free Tech Support: Call 866-217-0063 — if you're not sure which flex hose size you need, we can help you figure it out in under a minute
- Full Manufacturer Warranty: Backed by Castair's standard warranty
- OEM Parts: Factory-specification replacement parts, not aftermarket substitutes
Call 866-217-0063 for quick answers and help!
