Post Office Sponge Gaskets
Thousands of bespoke gaskets are manufactured and supplied daily by Advanced Seals & Gaskets Ltd, utilising not only standard sponge, foam, and rubber materials but also specialised alternatives. One of the most distinctive is Post Office Sponge, also known as orange open-cell natural sponge. This high-quality natural rubber is renowned for its bright orange colour and open-cell structure, making it ideal for applications where water absorption, flexibility, and reliable sealing are essential.
Enquire or Request Your Sample – Post Office Sponge Gaskets
Post Office Sponge is produced in blocks of various sizes and densities, with thicknesses of up to 80mm. These blocks can be precision-split down to as thin as 1.5mm and converted into finished products such as cut gaskets. At Advanced Seals & Gaskets Ltd, all gaskets are manufactured on-site using customer drawings, samples, or measurements. Whether you require a simple picture frame gasket or a complex design with notches, bolt holes, or cut-outs, we can deliver a cost-effective, high-quality solution.
Our machines are designed to handle both one-off prototype samples and large-scale production runs, ensuring every gasket is accurately formed. Gaskets can be supplied in plain form, laminated in layers, bonded with other materials, or coated with self-adhesive and foil finishes for ease of application.
Product Enquiry
For information on Post Office Sponge Gaskets please complete the following quick enquiry or call us on +44(0)1384 252555.
Characteristics of Using Post Office Sponge Rubber
Post Office Sponge is an open-cell natural rubber available in a range of densities from 140 to 600 Kg/m³. It is highly flexible, resilient, and can operate within temperatures ranging from -40 °C to +80 °C. The material’s tensile strength ranges from 0.23 N/mm² to 1.2 N/mm², depending on density, with elongation at break from 455% to 817%, offering excellent recovery after compression.
While it is highly absorbent and flexible, Post Office Sponge is not resistant to oils, acids, alkalis, or solvents, and it is highly flammable. Its unique characteristics make it perfect for wet applications, packaging, and low-pressure sealing where moisture absorption and compressibility are needed. Full technical data is available upon request or through our online portal.
Help and Guidance
If you require advice on the best Post Office Sponge Gasket for your application, our sales office is available to provide guidance. Please call us at 01384 469100 or email us directly. We can help you select the right gasket, provide technical support, or arrange a sample for testing.
Samples – Technical Post Office Sponge Gaskets
We offer sample gaskets for testing and evaluation. This allows you to verify the fit, flexibility, and sealing performance before committing to a full production run. Contact us to arrange a sample tailored to your needs.
Call now for sample requests or further help.
What are Post Office Sponge Gaskets?
Post Office Sponge Gaskets are precision-cut components made from orange open-cell natural sponge rubber. They are designed to fit between two surfaces, providing a low-pressure seal that prevents liquid or gas leakage and helps keep dust and debris out. The open-cell structure enables water absorption, while under compression, it can create an airtight or watertight seal.
Available in densities ranging from 160 Kg/m³ to 600 Kg/m³, and in different pore sizes, the material can be soft and flexible or firm and resilient depending on the application. This versatility makes it ideal for a wide range of applications, from packaging protection to wet environments and vacuum lifting systems.
Why use Post Office Sponge Gaskets?
While Post Office Sponge is not suitable for use with oils, acids, or alkalis, it excels in wet and moisture-related applications. Its ability to absorb water and recover quickly makes it perfect for packaging, labelling, and sealing applications, as well as creating vacuum lifting pads. The compressible structure also allows it to act as a dust and air barrier when adequate pressure is applied.
The material can be supplied as sheets or strips, or converted into bespoke gaskets with specific thicknesses and firmness, tailored to the level of compression and moisture absorption required by your application.
Benefits of Using Open Cell Natural Sponge Rubber
Post Office Sponge offers excellent abrasion resistance, making it durable in high-contact applications. Its soft and flexible nature allows it to seal around uneven or complex surfaces effectively, while the open-cell structure provides controlled water absorption for wet applications. The material recovers quickly after repeated compression, ensuring long-lasting performance, and it also exhibits good tear resistance, thereby enhancing its durability in demanding applications.
Other Grades of Sponge Materials Available
In addition to Post Office Sponge, we also supply a variety of specialist sponge and foam materials, including:
- EPDM – medium, firm, semi-open cell, and high-temperature resistant options
- Neoprene – flame-retardant, medium and firm grades
- Silicone – ideal for extreme temperature applications
- Polyurethane – versatile foam for cushioning and sealing
- Open Cell Industrial Sponge – multiple densities and grades available
This range ensures that, regardless of your application, we can supply the most suitable material for your needs.
The Advantages of Using Post Office Sponge Gaskets
Gaskets made from Post Office Sponge provide numerous benefits. Available in various densities and firmness levels, the open-cell structure enables the material to absorb liquids while providing cushioning and impact protection for delicate items. In packaging applications, it protects against damage and helps maintain moisture circulation when required.
When used in repetitive loading or compression scenarios, Post Office Sponge maintains excellent recovery, ensuring long-term reliability. Under sufficient pressure, the open cells compress and behave like a closed-cell material, sealing against dust, air, and moisture. This makes Post Office Sponge Gaskets a versatile, cost-effective, and dependable sealing solution for a wide range of industries.
Please contact us using the form below or by calling us on +44(0)1384 252555.