Compression fitting on plastic pipe - General Plumbing - BuildHub.org.uk

Zone valve came with compression fittings (olive + nut) on both ends. Speedfit pipe fits just about, but despite tightening the nut I can still turn it and with enough turning I can pull it out (and when filling the circuit under pressure it started moving out as by magic). The olive does not see

Compression fitting on plastic pipe - General Plumbing - BuildHub.org.uk

Compression fitting on plastic pipe - General Plumbing - BuildHub.org.uk

PlumbShop Brass Compression Fitting, 3/8-in OD x 1/2-in FIP, 1-pk

What are tube compression fittings, and how do they work?

1/2” threaded compression fitting for 16 x 2 mm homogeneous plastic pipes

LTWFITTING 1/4 in. O.D. Brass Compression Coupling Fitting (10-Pack) HF62410 - The Home Depot

MDCFCOUP - Easy Fit Compression Fitting System - Coupling