Page 9 - Parker - Assembly/Installation

4300 Catalog Assembly / Installation
Port End Assembly

Troubleshooting Port End Connections

60° Cone (Metric, BSPP and NPSM)

CONDITION PROBABLE CAUSE(S) RECOMMENDATION

End of swivel nut contacts hex • Wrong combination of swivel • Ensure that components are to the
shoulder of adapter before nut and adapter same specification (even with the same
cone and ball nose tightens type, there are different designs for
60° cone fittings)

Thread engagement seems • Scratches or nicks on sealing • Replace components. These fittings
adequate and swivel nut is surface depend on metal-to-metal seal and
tight but leakage still occurs • Chatter marks on sealing require smooth mating surfaces
surface to seal

There is leakage from the joint • Inadequate make-up torque • Use proper torque to create a seal as
and the swivel nut is loose well as prevent vibration loosening

Swivel nut tightens, cone is • Inadequate or no chamfer in • Use components with proper chamfer
tight but connection still leaks adapter (very common occurrence with NPTF/
NPSM 60° cone fittings). Male pipe end
must have chamfer for proper
sealing. Not all male pipe ends have
chamfer as standard

Tapered Thread (including BSPT, NPT and metric taper)

CONDITION PROBABLE CAUSE(S) RECOMMENDATION

Thread galling • Most common in stainless • Replace fitting and apply proper thread
steel, caused by friction and sealant/lubricant to replacement fitting
lack of lubricant and tighten to appropriate TFFT

Fitting leaks, even after • Sealant omitted or • Re-apply sealant to appropriate TFFT
proper tightening inadequately applied and re-tighten
• Damaged or cracked threads • Replace fitting
• Cracked port • Replace component
• Thread mixing of BSPT and • Determine port thread type and replace
NPT threads fitting with matching thread type
Insufficient thread • Quality problem with port or • Have port and adapter thread
engagement (3 to 6 threads adapter inspected; replace faulty parts
of engagement required) • Too much thread sealant (tape) • Remove all thread sealant and
re-apply 1 to 2 layers of tape

Too much thread engagement • Typically port or adapter • Inspect port and adapter for proper
(more than recommended 3 to machining or wear problem, tolerance or wear, replace faulty parts,
6 threads) or port could be cracked due retighten to appropriate TFFT
to excessive torque

Poor-quality threads or • Larger sizes are more prone to • Replace fitting with threads that
damaged/nicked threads having nicked threads due to are free of scratches and nicks
handling damage

Dimensions and pressures for reference only, subject to change.

S9 Parker Hannifin Corporation
Tube Fittings Division
Columbus, Ohio
http://www.parker.com/tfd