Rubber hoses are flexible conduits widely used in industries such as hydraulics, construction, agriculture, and automotive manufacturing, as well as in various types of equipment. They are characterized by flexibility, oil resistance, and wear resistance. Depending on the operating environment and the medium being conveyed, rubber hoses come in various types designed to suit different working conditions and meet diverse, complex fluid transfer requirements.
This article provides a comprehensive overview of rubber hoses—covering their structure, materials, manufacturing, types, applications, and selection criteria—to help you choose the right hose for your needs.
What is a rubber hose?
A rubber hose is a flexible conduit made primarily of natural or synthetic rubber, used to transport liquids, gases, chemical media, particulate matter, and other industrial substances. Its core function is to reliably convey fluid media and isolate them from the external environment under both dynamic and static conditions.
Rubber hose structure
A rubber hose is not a monolithic product; its structure consists of three layers: the inner tube, the reinforcement layer, and the outer cover.
Food Rubber Hose Structure
Inner tube: Direct contact with the medium
The innermost layer of the hose is known as the inner tube or inner liner; this is the primary factor determining the hose’s suitability for a given application. Since this layer comes into direct contact with the conveyed medium, the choice of material depends entirely on the medium’s chemical and physical properties.
For instance, hoses transporting petroleum-based fuels typically use nitrile rubber due to its excellent resistance to hydrocarbon solvents; hoses for high-temperature saturated steam might use EPDM rubber to withstand high-temperature oxidation and hydrolysis; and for food or drinking water applications, specialized rubber grades meeting hygiene standards—such as platinum-cured silicone—are used to ensure the hose is odorless, non-toxic, and resistant to bacterial growth. The surface smoothness of the inner tube is also crucial, as it directly affects fluid resistance and prevents particulate matter from adhering and causing blockages.
Reinforcement layer: The structural framework for mechanical performance
Positioned immediately outside the inner tube is the reinforcement layer; this is the core structure that enables the hose to withstand pressure, acting much like the steel framework of a building. The material used for the reinforcement layer, along with the braiding or spiraling method employed, determines the hose’s pressure-bearing capacity, resistance to impulse fatigue, and flexibility.
Common reinforcement materials include high-strength synthetic fiber cords (such as polyester or aramid), steel wire, or cotton cord. Fiber braiding offers good flexibility and moderate pressure resistance, making it common in general-purpose low-pressure hoses; steel wire braiding or spiraling can withstand extremely high pressures and is typically found in hydraulic hoses and blasting or excavation equipment; while natural fibers like cotton are often used in applications requiring static electricity dissipation. The number of reinforcement layers, the braiding angle, and the density are precisely calculated to balance pressure resistance, bending radius, and weight.
Outer Cover: A Protective Barrier Against the Environment
The outermost layer is the cover; its primary function is to protect the internal reinforcement and liner layers from external environmental hazards. This includes resistance to mechanical abrasion, UV radiation, ozone degradation, oil contamination, and extreme temperatures. Materials for the cover must exhibit good abrasion resistance, weatherability, and a certain degree of toughness. Neoprene is a common choice due to its balanced properties, including good resistance to oil and weather, as well as flame retardancy.
In specialized environments—such as those requiring high chemical resistance or suitability for food contact—the cover may be made from the same or similar specialty materials as the liner. Covers are often produced in specific colors (e.g., black, red, or orange); this serves not only aesthetic purposes but also acts as a visual indicator to distinguish between different applications.
Connection and Sealing: Critical System Interfaces
The hose itself is a flexible conduit; its functionality is realized by connecting it to rigid systems via fittings at both ends. The method of connecting the fitting to the hose constitutes another core technical aspect. The most common method is crimping, where specialized equipment forcefully compresses a metal fitting sleeve onto the hose cover, causing controlled deformation that bites into the reinforcement layer to create a mechanical interlock.
Another option is the reusable screw-type fitting, which is threaded into the hose and relies on friction for sealing, facilitating on-site replacement. Sealing design is equally important; it is typically achieved through an interference fit between the fitting’s conical insert and the hose’s inner bore, or by using an additional O-ring. Material selection for fittings (e.g., carbon steel, stainless steel, or brass) must take into account compatibility with the conveyed medium and the corrosiveness of the operating environment.
What materials are used to make rubber hoses?
The rubber material is the primary factor determining a hose’s application, as different rubber materials possess distinct properties. Rubber hoses utilize both natural and synthetic rubbers; there is a wide variety of synthetic rubbers, with the following being the most common:
Natural Rubber (NR)
Natural rubber is produced from latex harvested from rubber trees. It offers excellent abrasion resistance, high elasticity, high tensile strength, and high elongation. However, it is prone to aging when exposed to air, becomes sticky when heated, and swells or dissolves in mineral oils or gasoline; while resistant to alkalis, it is not resistant to strong acids.
Natural Rubber
Styrene-Butadiene Rubber (SBR)
A copolymer of butadiene and styrene. Compared to natural rubber, it offers more uniform quality and fewer impurities, as well as superior abrasion and aging resistance, though its mechanical strength is lower; it can be blended with natural rubber. Hoses made from SBR are not recommended for contact with strong acids, ozone, oils/greases, or most hydrocarbons.
Ethylene Propylene Diene Monomer (EPDM)
A copolymer of ethylene and propylene, offering excellent heat, aging, and ozone resistance, as well as high stability. It cannot be vulcanized with sulfur and typically operates within a temperature range of -50°C to 150°C. It features good weatherability and excellent water and chemical resistance; it is compatible with alcohols and ketones, withstands high-temperature steam, and offers low gas permeability. It is commonly used as a raw material for steam hoses.
Nitrile Rubber (NBR)
A copolymer of acrylonitrile and butadiene, with an acrylonitrile content ranging from 18% to 50%. Higher acrylonitrile content improves resistance to petrochemical oils and hydrocarbon fuels but compromises low-temperature performance; the typical operating temperature range is -25°C to 100°C. It offers good compression characteristics, abrasion resistance, and elongation properties, making it one of the most common materials for oil seals and O-rings. However, NBR hoses are unsuitable for contact with polar solvents (such as ketones) or ozone.
Fluoroelastomer (FKM)
FKM hoses are made from a high-grade rubber material typically used to convey high-temperature, highly corrosive chemical media. They offer excellent resistance to corrosion, high temperatures, abrasion, and oxidation. FKM hoses are suitable for transporting media such as acids, alkalis, solvents, and alcohols.
Silicone Rubber (SR)
Silicone rubber hoses feature excellent resistance to high temperatures, oxidation, and radiation; they are capable of long-term use at high temperatures and can operate in environments involving oxygen, ozone, and various gases. They are suitable for conveying high-temperature fluids in sectors such as the automotive, marine, aerospace, and railway industries.
Chloroprene Rubber (CR)
Chloroprene rubber hoses are made from a versatile material primarily used to convey media such as natural gas, industrial gases, ethylene, vinyl acetate, alcohols, petroleum products, and water. These hoses offer excellent resistance to oil, chemicals, weathering, and abrasion, making them suitable for a wide range of industrial and civil applications.
Rubber Hose Manufacturing Process
Raw Material Preparation and Compounding
Natural or synthetic rubber is selected and combined with additives such as vulcanizing agents and anti-aging agents. After mastication to soften the material, it is mixed in an internal mixer under high temperature and pressure to form a homogeneous rubber compound.
Mandrel Coating
A mandrel of the appropriate diameter is selected, and a release agent is applied to its surface.
Extrusion Molding
The rubber compound is processed through a hot-feed or cold-feed extruder to continuously extrude the inner rubber layer. The extruded inner layer immediately enters a water trough for cooling to prevent deformation.
Reinforcement Layer Construction
The structure and material of the reinforcement layer vary based on the hose’s pressure rating; low-pressure hoses typically use fiber braiding or knitting, while high-pressure hydraulic hoses utilize steel wire braiding or spiraling.
Outer Rubber Extrusion
The outer rubber layer is extruded over the reinforcement layer to protect the hose’s structural integrity. The material of the outer layer may differ from that of the inner layer, as the inner layer contacts the conveyed medium while the outer layer is exposed to the external operating environment. The outer layer also requires cooling after extrusion.
Marking/Labeling
Logos, model numbers, and size specifications are printed on the outer rubber layer; custom markings can be applied according to customer requirements.
Vulcanization
The semi-finished hose assembly (still on the mandrel) is placed in a vulcanization autoclave. It is heated and pressurized (typically between 140°C and 180°C) to cross-link and cure the rubber molecules, thereby achieving the required elasticity and strength.
Mandrel Removal
After cooling, the mandrel is removed, and the hose undergoes trimming (removal of flash/burrs), dimensional measurement, and cutting to specification.
Pre-shipment Inspection
Inspections cover inner and outer diameters, appearance, and markings. To ensure quality, the hose undergoes pressure testing, bend radius verification, abrasion resistance testing, and burst pressure testing. Impulse testing is also conducted for hoses intended for high-pressure, high-impulse applications.
Assembly and Packaging
Metal fittings (crimp-style or screw-on) are attached where required. Following final inspection, the hoses are coiled, packaged, and prepared for shipment.
Types of Rubber Hoses
Types of Industrial Rubber Hoses
Water hoses: Used in irrigation, gardening, construction, firefighting, etc.; inner tube materials are typically PVC or EPDM.
- Air hoses: Used for compressors, pneumatic devices, etc.; inner tube materials are typically NBR, PVC blends, PU, or SBR.
- Oil hoses: Used for fuel, diesel, kerosene, etc.; inner tube materials are typically NBR, PVC blends, or SBR; conductive steel wire is usually embedded between the inner and outer rubber layers.
- Chemical hoses: Used for acids, chemical solutions, etc.; inner tube materials are typically UHMWPE or EPDM; materials and designs often require customization.
- Hot water and steam hoses: Used for cooling water in refrigeration equipment, food processing, etc.; inner tube material is typically EPDM.
- Beverage and food hoses: Used for milk, carbonated drinks, beer, etc.; inner tube materials are typically NR or synthetic rubber (NBR, silicone, or EPDM); must meet food-grade certification standards.
- Welding hoses: Used for gas welding, cutting, etc.; inner tube materials are typically NBR or synthetic rubber; outer rubber colors indicate the specific gas type.
- Material suction and discharge hoses: Used to transport fluids containing solid particles; inner tube materials are typically NR, NBR, SBR, or PU.
- Engineering hoses (e.g., concrete hose or sandblasting hoses): Due to the operating environment, these hoses require excellent abrasion resistance; inner tube materials are typically NR/SBR.
Application Areas of Rubber Hoses
Industrial Manufacturing and Distribution
Widely used in sectors such as petroleum, chemicals, shipbuilding, and tanker transport; capable of conveying media including gas, water, steam, mist, slurry, sand, and waste materials. Applications span hot and cold water systems, ventilation, cooling, fire protection, and hydraulics.
Industrial Rubber Hose Application
Offshore Engineering and Onshore Oil & Gas
Used in offshore drilling and production equipment, deep-sea mining machinery, onshore oil and gas equipment, and large-scale storage facilities. Hoses in these environments must withstand high pressure, high temperatures, and corrosion.
Construction Machinery Industry
Serves as a component in the hydraulic systems of various construction machines, conveying hydraulic fluid to ensure proper operation.
Automotive Industry
An essential component of automotive braking, cooling, and fuel systems; used to transport fluids such as brake fluid, coolant, and fuel.
Agricultural Sector
Primarily used for irrigation in agriculture and landscaping to deliver water to crops; also utilized for transporting fertilizers and grain.
Food and Beverage Industry
Food-grade rubber hoses are used in dairy plants and beverage production lines to convey high-temperature hot water or steam for equipment sterilization and cleaning.
Pharmaceutical Industry
Used during pharmaceutical manufacturing processes to transport specialized medicinal fluids or gases.
Construction Industry
Applied in centralized heating systems for large commercial buildings and industrial plants, connecting boilers to heat-emitting terminals; also used in central air conditioning systems to transport high-temperature steam or condensate.
Fire Protection Sector
Large-scale fire protection systems utilize rubber hoses to deliver water or fire-extinguishing agents during firefighting and rescue operations.
Advantages and Limitations of Rubber Hoses
Rubber hoses offer numerous advantages—such as flexibility, ease of installation, compatibility with a wide range of media, and vibration/noise reduction—that set them apart from rigid piping. However, they also have drawbacks, including susceptibility to aging and failure, limited mechanical strength, vulnerability to damage by insects and rodents, and constraints regarding temperature and pressure resistance.
How to Select the Right Rubber Hose?
When selecting rubber hoses, it is essential to consider the application environment, the conveyed medium, and other physical properties. Specific factors to consider include:
Application Environment and Medium Properties
Medium Type: Identify the type of fluid to be conveyed (e.g., chemicals, oils, gases) and its physical and chemical properties.
Operating Conditions: Consider temperature ranges, pressure ratings, and the presence of corrosive or abrasive substances.
Physical Properties
Pressure Resistance: Select a hose capable of withstanding the specific operating pressure to ensure safe operation.
Flexibility and Rigidity: Choose the appropriate level of flexibility based on installation space and usage scenarios to accommodate dynamic loads.
Abrasion and Tear Resistance: In high-wear environments, prioritize materials with superior abrasion and tear resistance.
Dimensions and Length
Inner Diameter and Wall Thickness: Ensure compatibility with fluid flow rates to avoid excessive pressure drops or flow velocity limitations.
Length Selection: Select a suitable hose length based on equipment layout and operational requirements.
Connections and Fittings
Fittings: Choose high-quality fittings compatible with the hose to ensure secure and leak-proof connections.
Ease of Installation: Consider the ease of installation and removal, particularly for scenarios requiring regular maintenance or cleaning.
Safety and Compliance
Standards Compliance: Ensure the hose meets relevant safety and quality standards (e.g., ISO, GMPHOM).
Emergency Preparedness: Consider the hose’s performance under extreme conditions and strategies for handling potential failures.
Cost-Effectiveness
Initial Investment: Balance performance against price to select a product with good value for money.
Maintenance and Replacement Costs: Evaluate the total cost of ownership by considering the hose’s expected lifespan, maintenance requirements, and replacement costs.
Storage of Rubber Hoses
Proper daily storage is crucial for maintaining the performance stability and extending the service life of rubber hoses; improper storage can easily lead to issues such as aging, deformation, and cracking.
Storage of Rubber Hoses
Temperature and Humidity Control
The ideal storage temperature is 10–25°C. Low temperatures cause the rubber to harden and lose elasticity, making it prone to cracking when bent.
High temperatures accelerate the oxidation of rubber molecules, leading to softening, swelling, or premature aging (especially in hoses containing plasticizers).
Keep away from heat sources (such as radiators, boilers, and areas with direct sunlight). Maintain relative humidity between 50% and 70% to avoid dampness (which promotes mold growth) or excessive dryness (which causes the rubber to become brittle).
Protection Against Light and Ozone
Store rubber hoses in a dark place or cover them with opaque canvas or cardboard boxes; do not store them directly outdoors.
Keep away from ozone sources such as high-voltage motors, welding machines, photocopiers, and disinfection cabinets. Ensure the storage area is well-ventilated to prevent ozone accumulation, and use ozone absorbers if necessary.
Proper Stacking and Positioning
Rubber hoses should be stored laid out straight or coiled. When coiling, the coil diameter must be at least 10 times the hose’s inner diameter to prevent damage to the internal reinforcement layer caused by excessive bending.
Do not hang or suspend hoses vertically, as their own weight can cause stretching and deformation. When stacking, the height should not exceed 1.5 meters; use pallets or racks to support the bottom layer and prevent deformation due to pressure.
Store hoses of different materials, specifications, and intended uses separately (e.g., keep high-temperature hoses separate from standard water hoses, and food-grade hoses separate from industrial hoses) to avoid material incompatibility (such as swelling caused by contact with oils).
Do not store alongside sharp objects (e.g., metal edges, tools) or corrosive substances (acids, alkalis, solvents) to prevent surface scratches or chemical corrosion.
Avoid Contact with Harmful Substances
Keep the storage area floor clean and free of oil stains or chemical residues; use oil-resistant mats if necessary. Keep away from oils and solvents to prevent contamination.
Food-grade rubber hoses must be stored in sealed packaging (e.g., wrapped in plastic bags) and kept free from dust, oil, or industrial contaminants to ensure compliance with hygiene standards during use.
Conduct regular inspections and repositioning.
Inspect the condition of stored hoses every three months for surface cracks, discoloration, or adhesion (often caused by high temperatures or plasticizer migration); address any issues promptly (e.g., separating stuck hoses or discarding aged products). Reposition stacked hoses monthly to shift load-bearing points and prevent deformation caused by prolonged pressure on a single area; uncoil and re-coil stored hoses periodically to prevent aging at fixed bend points.
Label stored hoses with specifications, material, date of entry into storage, and expiration date (standard rubber products typically have a shelf life of 2–3 years, while special materials like fluoroelastomer may last up to 5 years). Prioritize the use of products nearing their expiration date to avoid performance degradation caused by prolonged storage.
FAQ
Are silicone hoses better than rubber?
Silicone hoses excel in high/low-temperature resistance (-60°C to 200°C) and cleanliness, but they are expensive and have very poor oil resistance. Rubber hoses, on the other hand, offer distinct advantages in oil resistance, high-pressure tolerance, and cost-effectiveness, making them suitable for fuel and hydraulic systems. Each type has its own strengths; the choice depends on specific operating conditions.
How long does a rubber hose last?
Under ideal storage conditions, the shelf life of a rubber hose is typically 10 years. However, its actual service life—generally ranging from 5 to 10 years—is influenced by factors such as temperature, pressure, and the operating environment.
How much pressure can a rubber hose handle?
Pressure ratings vary by hose type, construction, and specifications, ranging from a few bar to several hundred bar (thousands of PSI). Steel-wire-reinforced rubber hoses can withstand working pressures of up to 50 MPa.
Are rubber hoses the same as hydraulic hoses?
Not exactly. Hydraulic hoses can be considered a specific, major category of rubber hoses. Hydraulic hoses are subject to stricter standards and are designed to withstand higher pressures.
What is the difference between composite hoses and rubber hoses?
The main differences lie in construction and application. Composite hoses are made from multiple layers of materials; they are lightweight, flexible, and chemically resistant but have moderate pressure tolerance. Rubber hoses feature a three-layer structure—inner and outer rubber layers with fiber or steel wire reinforcement—offering superior pressure and oil resistance at a lower cost than composite hoses.
Can rubber hoses be left outside in winter?
Leaving rubber hoses outdoors in winter is not recommended. Rubber materials harden and become brittle at low temperatures; prolonged exposure to extreme cold accelerates hardening, making the hose more prone to cracking when moved or bent. If short-term use or temporary outdoor placement is unavoidable, be sure to drain any accumulated water after use.
Why Choose Strongflex Rubber Hose?
Strongflex is a rubber hose manufacturer that maintains strict quality control throughout the entire process—from raw materials to production and packaging—and takes full responsibility for after-sales service. Raw materials undergo testing across multiple parameters, including rubber compound vulcanization curves, hardness, tensile strength, and steel wire tensile strength.
Dual online and offline quality inspection systems are employed during production; each hose is assigned a unique identification code that records production data, ensuring full quality traceability.
The product portfolio is extensive, offering a wide range of types and comprehensive size specifications suitable for applications across various industries.