Highpressure tubes

Highpressure tubes

We hold extensive stocks of seamless high-pressure tubing manufactured to the most stringent quality specifications. The high-pressure pipes are characterized by a high yield point and high tensile strength in combination with high elongation. The pressure resistance is guaranteed by the very smooth inner surface. Autofrettage treatment prolongs cycle fatigue behavior (see below).

The high-pressure pipes are available in the pressure levels:

Highpressure-Nipples

We manufacture high pressure nipples as standard products or to specific customer requirements. At the customer’s request, we can also refine high-pressure nipples with an autofrettage treatment.

Coils

The coiled tubing is available in grades for both pressure ratings:

Autofrettage

Autofrettage is a process to increase the resilience of components subjected to internal pressure, which can significantly increase their service life. The effect of autofrettage is based on the targeted induction of residual compressive stresses, which counteract the tensile stresses in the application.
When the component is subjected to a one-off load at very high internal pressure, which is significantly higher than the operating pressure that will later be required, various deformation zones occur (see image). During relaxation, the elastically deformed area pushes back to its original state and presses on the plastically deformed area inside. This results in the desired internal stresses.

Components that are subject to high pressure and are exposed to a constant change between high and low pressure are, in particular, components for diesel injection technology (rail, injector nozzles, pump housing, etc.), components for water jet cutting technology and components for high and ultra-high pressure technology (pipes, fittings).
ALLFI offers you autofrettage with pressures of up to 14,000 bar as a finishing service.