Synertech Stock
Product codes
Details
GDI and GDIM rod seals are unidirectional dynamic seals with an asymmetric lip, designed mainly for pneumatic cylinders and light-duty hydraulic actuators. The geometry differentiates the functions of the two lips: the outer lip, taller and more robust, ensures static stability within the groove, while the inner lip, shorter and more flexible, provides dynamic sealing on the rod, reducing friction and stick-slip phenomena.
GDI and GDIM
GDI Standard Type
Asymmetric profile with inch dimensions, featuring sharp-edged finished lips. It is suitable for cylinders and housings based on British or American dimensional standards.
GDIM Type
Geometric variant developed for metric dimensions, with negative-cut finished lips to facilitate initial sliding and reduce stick-slip.
Materials and operating conditions
| Material | Compound | Linear speed | Temperature | Max pressure |
|---|---|---|---|---|
| Nitrile rubber | NBR 90 Shore A | Up to 0.1 m/s | −30 / +100 °C |
Up to 2.0 MPa 20 bar in pneumatic applications |
Seal body
Options on request
Lubricated or dry compressed air, industrial greases and hydrocarbon-based mineral oils.
Main features
Sharp-edge cut
The geometric finish of the lips promotes the removal of the fluid film or condensation present on the rod, reducing the drag effect and improving dynamic sealing performance.
Outer retaining lip
The outer lip is intentionally taller and generates strong mechanical interference within the housing, counteracting axial displacement of the seal during cycle reversals.
Optimized flexibility
The flexibility of the lips is designed to provide low-friction operation during rod movement, limiting localized wear.
Advantages of the GDI / GDIM profile
Pneumatic versatility
The geometry of the inner lip allows use with both lubricated and dry compressed air, extending the range of applications in pneumatic systems.
Interchangeability
GDI and GDIM geometries are designed to facilitate interchangeability with commercial profiles used in major industrial pneumatic applications.
Simplified installation
The elasticity of the NBR 90 Shore A compound allows manual insertion of the seal into closed grooves without requiring dedicated mechanical deformation tools.
Typical applications
- Standard industrial pneumatic cylinders and linear actuators for factory automation
- Linear handling systems in the packaging, bottling and textile industries
- Pneumatic control valves and manifold valves with through rods
- Light-duty hydraulic cylinders and micro-actuators operating at low pressure
- Clamping and workholding devices on industrial machine tools
Interchangeability
Nominal dimensions, tolerances and radial housing grooves are defined according to industrial profile interchangeability specifications and the corresponding surface roughness parameters.
Market equivalents
| Manufacturer / Distributor | GDI / GDIM Standard Type |
|---|---|
| Net Seals | GDI / GDIM Rod Seal Series |
| ATS Srl | DI-DIM Pneumatic Profile |
| Extended interchangeability | SNI24 / LDIMC / DI / IUH / PDI / MRUN |