Integral Seal Screws and Plugs from Automotion
Our large range of mechanical components offers solutions to everyday machine and tooling assemblies. The range includes: captive screws and shoulder screws of every head and size, special sealing screws, nuts and washers, dowel pins, levelling feet and lifting bolts.
As specialists in mechanical components our knowledgeable technical support team can assist with your project, whether you need help picking the right corrosion resistant screws for marine applications or calculating the precise sealing plugs needed for your hydraulic systems.
Make sure you also request a free Mechanical Components Handbook here and utilise our freely available CAD files to save time planning your projects.
Applications
Some of the typical applications for our sealing screws include:
- Motors
- Cabinets and enclosures
- Sensors and instrumentation
- Internal combustion engines
- Gear pumps
- Fuel tanks
- Transmissions
- Gear boxes
- Air cylinders
- Pressure gauges
- Computer disk drives
- Motion control valves
- Missle tanks
- Wet wings
General Guidance
An ordinary screw lacks seal protection, allowing dirt, fluids, gases etc. to infiltrate and damage sensitive devices. Sealing screws provide bi-directional sealing protection to systems where screws are used, to protect them against dirt, chemicals, water or other contaminates, which (without the screw seal), may penetrate and damage or alternatively where gases and liquids may leak out.
The seal screws incorporate an O-ring underneath the screw, bolt etc. which forms a sealant layer. The seal provides bi-directional sealing. The screws are very easy to use and do not need any special preparation or re-tightening
Integral seal fasteners are designed and manufactured with a precision engineered groove beneath the head of the fastener. As the fastener is tightened, the O-ring is compressed, squeezing the O-ring between the groove and mating surface to complete the seal. The design of the groove controls the amount of compression of the O-ring and because O-rings retain theirelastic memory, the screws are reusable time after time.
There are a range of O-ring materials that can resist virtually all chemical and environmental conditions. We can also provide sealing screws (on request) to military specifications (MILSPEC).
The screws are widely used in military, medical and industrial devices. Each screw is equipped with a captive O-ring which provides a total barrier seal agaianst internal and external conditions (water, fluids, chemeicals, dirt, air, contaminates etc.) which colud otherwise penetre and damage systems.
When using self-sealing screws a high pressure seal is formed along the thread's contact surface when torqued.
If possible, and to ensure maximum sealing performance, we recommend a clearance hole. This creates room for the O ring to flow into.
The aim is to ensure full metal-to-metal contact between the underside of the fastener and the mounting surface.
If the counterbore cannot be applied, the O ring will still function as it will squeeze fit the gap between the male and female surfaces.
