Silicone Inflatable Seal Plug

Bombay Rubber & Carbon Works lists small inflatable seal plugs in the 25–500 mm range, while also offering smaller and non-standard sizes. The company additionally reports a small-diameter auto-coupler seal capable of 10 bar pressure. Final operating pressure must be established for the specific plug geometry, material, expansion and test conditions.

Pipe Leak Testing

The primary application of the Silicone Inflatable Seal Plug is temporary sealing during pipe and tube leak testing.
Applications include:
• Pipe leakage testing
• Tube testing
• Plumbing components
• Industrial pipelines
• Hydraulic lines
• Fluid-transfer components
• Process piping

The manufacturer specifically identifies pipe testing and leakage testing as the principal applications for its inflatable seal plug.



Pressure Testing

Inflatable plugs can be incorporated into pressure-testing fixtures where a section of a component needs to be isolated before applying test pressure.
Potential applications:
• Pipe pressure testing
• Tube pressure testing
• Valve testing
• Connector testing
• Component validation
• Hydraulic testing
• Pneumatic testing

The plug design can be engineered according to the required pressure, sealing diameter and test cycle.



Automotive Component Testing

Small-diameter inflatable plugs are particularly useful for automotive components with restricted installation space.
Applications include:
• Auto couplers
• Fuel-system components
• Fluid connectors
• Pipes and tubes
• Valves
• Cooling-system components
• Hydraulic components

Bombay Rubber & Carbon Works specifically references a small-diameter auto-coupler seal developed for a demanding application.



Valve Testing

Inflatable seal plugs can be used to isolate sections of valves and related components during leakage or pressure testing.
Applications include:
• Industrial valves
• Control valves
• Process valves
• Hydraulic valves
• Pneumatic components
• Special-purpose valves



Tube & Connector Testing

Small inflatable plugs can be especially useful for components with small internal diameters where conventional mechanical test plugs may be difficult to install.
Applications include:
• Tubing
• Connectors
• Couplings
• Fittings
• Fluid-transfer assemblies
• Small-diameter components



Industries Served

Automotive
Used for testing fuel, hydraulic, coolant and fluid-transfer components.

Pharmaceutical
Silicone versions can be selected for suitable pharmaceutical equipment and high-purity applications.

Food & Beverage
Appropriately certified silicone compounds can be considered for food-processing equipment and testing applications.

Chemical
FKM, EPDM or other suitable compounds can be selected according to the chemical environment.

Oil & Gas
Specialized materials and reinforced designs can be engineered for demanding pipeline and component-testing applications.

Industrial Machinery
Suitable for production testing, quality control and component validation.

Medical & Laboratory
Specialized silicone inflatable plugs can be developed for controlled laboratory and medical-component testing environments.

Advantages For Testing Systems

Fast Testing Cycles
Inflation and deflation can be pneumatically controlled for rapid testing operations.

Easy Insertion & Removal
The plug remains compact while deflated and expands only when sealing is required.

Repeatable Sealing
The inflatable design can provide consistent contact during repeated test cycles when correctly designed and maintained.

Small-Diameter Capability
Specialized inflatable plugs can be developed for very small internal diameters.

Custom Pressure Capability
The seal construction can be engineered according to the required test pressure and sealing conditions.

Reduced Mechanical Complexity
Compared with some mechanical plugs, pneumatic expansion can simplify the sealing and release operation.



Fabric-Reinforced Options

For applications involving higher pressure requirements, fabric reinforcement can be incorporated into the inflatable seal construction.
Fabric reinforcement provides:
• Improved dimensional stability
• Increased pressure capability
• Greater mechanical strength
• Better resistance to excessive expansion
• Improved performance in demanding applications

Bombay Rubber & Carbon Works states that its fabric-reinforced inflatable seals can be engineered for high-pressure applications and reports designs with bursting pressure up to 50 bar, depending on construction and application.
For nominal-pressure applications, the manufacturer’s general guidance recommends avoiding unnecessary fabric reinforcement where it would add cost without providing a functional benefit. For pressure differentials above approximately 7–8 bar, fabric reinforcement may be considered.

How It Works

1. Insertion
The deflated inflatable plug is inserted into the pipe, tube or component that requires testing.

2. Positioning
The plug is positioned at the specified sealing location.

3. Inflation
Controlled compressed air or another suitable inflation medium is introduced through the inflation connection.

4. Seal Expansion
The silicone inflatable body expands and presses against the internal or designated sealing surface.

5. Testing
The component is subjected to the required pressure, vacuum or leakage test while the plug maintains the temporary sealing boundary.

6. Deflation
After the test is completed, inflation pressure is released.

7. Removal
The plug retracts and can be removed from the component with minimal resistance.

This inflate–test–deflate operating cycle makes the seal plug particularly useful for repetitive production-line testing and inspection fixtures.



Design & Selection Guide

Correct selection of an inflatable seal plug depends on the actual testing conditions. Important design parameters include:
• Internal pipe diameter
• Minimum and maximum diameter tolerance
• Required sealing expansion
• Test pressure
• Inflation pressure
• Test medium
• Operating temperature
• Chemical exposure
• Required leakage limit
• Number of test cycles
• Available installation space
• Plug insertion depth
• Inflation port location
• Required material
• Requirement for reinforcement
• Manual or automated operation

The manufacturer’s general inflatable-seal guidance also recommends considering environment, expected life, pressure differential, inflation gap, equipment geometry, air connector, retention mechanism and over-pressure safety during design.



Custom Design & Manufacturing

Every pipe, tube and test fixture can have different dimensional and pressure requirements.
Customized Silicone Inflatable Seal Plugs can be developed based on:
Drawing → Diameter Selection → Material Selection → Profile Development → Prototype → Testing → Production

Customers can provide:
• Engineering drawing
• Sketch
• Existing seal sample
• Component sample
• Pipe dimensions
• Test pressure
• Test medium
• Temperature requirements
• Required cycle life

Bombay Rubber & Carbon Works specifically offers customized inflatable seal development and invites customers to provide a sketch or drawing for product development.



Quality & Performance

Depending on the selected material and application, documentation may include:
• Material test certificate
• Dimensional inspection report
• Pressure test report
• Leak-test report
• Certificate of conformity
• FDA documentation for applicable silicone compounds
• Customer-specific quality documentation

For critical applications, the final seal should be validated under the actual test pressure, temperature, medium and operating cycle before production deployment.



Why Choose Silicone Inflatable Seal Plugs?

Precision Sealing
Designed to provide controlled expansion against the test surface.

Quick Operation
Fast pneumatic inflation and deflation support efficient testing.

Custom Sizes
Available in standard and non-standard diameters.

Flexible Material Options
Silicone, NBR, EPDM, FKM/Viton® and Neoprene can be selected according to application requirements.

High-Pressure Options
Reinforced constructions can be developed for demanding pressure-testing applications.

Reusable Design
Suitable for repeated testing cycles when properly engineered and maintained.



Engineered For Accurate & Repeatable Testing

Silicone Inflatable Seal Plug — Precision temporary sealing for pipe testing, leak testing, pressure testing and industrial component inspection.
Pipe Testing | Leak Testing | Pressure Testing | Small-Diameter Sealing | Custom Sizes | Silicone Construction | Industrial Quality Control