Maybe you have seen rubber, maybe you have seen rubber hydraulic hose, but do you know how to make hydraulic hose? Strongflex shows you the production process of hydraulic hoses step-by-step. Through this article, you will know how the high-quality hydraulic hoses you receive are produced, what tests did they undergo? It contains the unique operating procedures of our factory. You are welcome to visit our factory at any time.
What Is a Hydraulic Hose and Its Structure?
Before exploring the manufacturing process of hydraulic hoses, it is helpful to first understand what a hydraulic hose is and how it is constructed.
Hydraulic hoses—also known as hydraulic oil hoses—are capable of conveying not only water and air but also hydraulic fluid for the transmission of hydraulic power. They are subject to rigorous industry standards (such as DIN, SAE, ISO, and GB) and outperform standard hoses in terms of both general performance and pressure-bearing capacity.
A hydraulic hose primarily consists of a fluid-resistant inner rubber layer, an intermediate rubber layer, a reinforcement layer (comprising two, four, or six layers of spirally wound steel wire), and an outer rubber layer. The inner rubber layer enables the conveyed medium to withstand pressure and protects the steel wire from corrosion; the outer rubber layer shields the steel wire from damage; and the steel wire layer serves as the structural framework, providing reinforcement.
1. Inner Rubber Layer: This layer comes into direct contact with the fluid medium, ensuring compatibility and containment while withstanding operating pressure and preventing leaks. Common materials include oil-resistant synthetic rubber (such as Nitrile Rubber/NBR), polyurethane, or PTFE.
2. Reinforcement Layer: This layer provides the mechanical strength required to withstand high pressure and tensile stress, thereby determining the hose’s pressure rating. High-strength steel wire is commonly used for medium-to-high-pressure and heavy-duty applications, utilizing either a braided or multi-layer spiral-wound structure. Fiber fabrics or polyester cords (such as nylon or polyester fibers) are typically used for low-pressure or light-duty hoses.
3. Outer Rubber Layer: This layer protects the internal structure from mechanical abrasion, chemical corrosion, UV degradation, and weather-related damage. Common materials include wear- and weather-resistant synthetic rubber (such as Neoprene/CR or Nitrile Rubber) or thermoplastics (such as nylon or polyurethane). In harsh operating environments, a metal outer wrap or an additional protective sleeve may also be employed.
How to Make Hydraulic Hoses?
1.Material Selection
The process begins of Strongflex hose with selecting the high quality raw materials.
1.1 Rubber
Commonly used rubber types are neoprene rubber (NBR), butyl rubber (BR), natural rubber (NR), and Styrene-butadiene rubber (SBR).
1.2 Steel wire:
Commonly used steel wire materials include high-carbon steel wire, low-carbon steel wire, high tensile steel wire, stainless steel wire, etc.
1.3 Textiles:
Commonly used textiles include cotton yarn, nylon, polyester, etc.
How can we ensure that the materials are high-quality? We will carry out hardness test and vulcanization test on raw rubber, tensile test on steel wire, adhesion test between steel wire and rubber, etc. If you want to know more test details, you can read other article – Quality Control of Hydraulic Hoses.
2.How Are Hydraulic Hoses Made?
How to make hydraulic hose
2.1 rubber mix
The inner layer rubber, the middle layer rubber and the outer layer rubber are mixed according to the formula by using CNC mixer; The amount of rubber and other additives is controlled precisely to improve the strength, abrasion resistance and high temperature resistance of rubber.
2.2 Prepare the core
We will choose the soft core or hard core according to the requirements of the hydraulic hose, after choosing, we will measure the size of the mandrel. 
Hydraulic Hose Core RodDuring use, flexible mandrels undergo vulcanization, causing them to shorten and their diameters to increase; this directly leads to dimensional deviations in the hose’s inner diameter. To minimize this error, each mandrel is used only 20 to 30 times, ensuring the hose diameter strictly complies with standards.
2.3 rubber tube extrusion
Prepared raw materials are extruded through an extruder, During the extrusion process, we need to control factors such as temperature and pressure to ensure the quality and uniformity of the hose.
2.4 steel wire merge
Steel wire is a common reinforcing material used in hydraulic hoses, steel wire merging can increase the strength and pressure resistance of hydraulic hoses. We use advanced technology steel wire joint machine controled by PLC. When the steel wire bobbin make braiding or spiraled, no any connection occurs. We can control quality from inside to outside.
2.5 Braided or wound reinforcement
We use Germany technology braiding machines working braiding in 3X3. Steel wire or wire rope is wound or braided around the rubber inner layer to enhance the tensile strength and pressure resistance of the hose. We used Germany technology Spiraled machine to produce 4SP, 4SP, R12 and R13, R15.
2.6 Outer hose extrusion
Put the reinforcement layer and the inner rubber tube into the extruder, and then extrude the outer rubber tube. Apply the outer layer of glue to the extruder, and then wrap the lead or cloth vulcanization protective layer.
The markings on the hydraulic hoses are fully customizable; they can display your company name and specifications. You can also choose the color and the hose’s exterior finish (such as cloth-impression or smooth). We can even assist you in designing the markings to your satisfaction.
2.7 Remove core
After the vulcanization process is complete, the rubber core is removed from the inner tube.
Vulcanizing tank
2.8 Remove the protective layer
Finally remove the vulcanized protective layer.
The most important point is that we will give each hose an Identified Card, which contains information about the production equipment, production date and production personnel, so as to trace the quality at a later stage.
Quality Inspection after Production
After production, we will inspect each hose, visual inspection includes the measurement of inside and outside diameter, the inspection of the appearance of the marking, and so on, we also carry out more in-depth testing, the most critical point, we test proof pressure to avoid any leakage.
Based on our test results, we will classify the tubes, only the absolutely qualified finished products will be stored or packed and shipped to customers. Don’t worry, if you are not satisfied with the product you received, feel free to contact us, not only can we track the quality according to the identified card, but we will also proactively provide a satisfactory solution.
How to Choose a Hydraulic Hose Manufacturer?
When selecting a hydraulic hose manufacturer, one should not focus solely on price; instead, factors such as production capacity, product quality, service, and after-sales support should be carefully considered. Before placing large-volume orders, it is highly advisable to conduct an on-site visit to the factory.
Key factors to consider when choosing a hydraulic hose manufacturer include:
Manufacturer’s production capacity and authenticity: Does the company own its factory and production team? Does it possess active production lines and genuine manufacturing capabilities and equipment?
Product quality and quality control: While the ability to manufacture is the foundation, the ability to produce high-quality goods is essential. Do the hoses meet relevant standards and international industry requirements? Does the manufacturer have an in-house quality inspection system, conduct honest inspections, and maintain robust quality control throughout the production process?
Product range and customization capabilities: Can the manufacturer provide hoses with various pressure ratings, sizes, structures, and application suitability to meet downstream needs (such as hose assemblies)? Do they support customization of specifications—including length, fittings, branding, packaging, color, and appearance? This is crucial for distributors and traders and should be clarified in advance.
Technical support and after-sales service: Can the manufacturer assist customers in selecting the right hoses, fittings, pressure ratings, sizes, and assembly configurations? Is there a comprehensive after-sales support system in place?
Delivery capabilities and export experience: Factors such as lead times for standard products and possession of export qualifications are also important aspects to evaluate.
What Should You Check When Visiting a Hydraulic Hose Factory?
When conducting an on-site visit to a hydraulic hose factory, one should focus on various details, including raw material quality, manufacturing processes, quality control systems, and production inspections.
Raw Material Quality: Examine the raw materials—such as steel wire and rubber—used in production, as well as filtration procedures and raw material inspection protocols. Raw materials directly impact the quality of the finished product; for instance, Strongflex analyzes the vulcanization curve for every batch of rubber to determine the optimal vulcanization time for achieving the best strength and hardness. We also test the adhesion between the rubber and steel wire to ensure that the inner tube and reinforcement layer do not separate during use.
Production Site: Observe whether the production floor is organized and orderly, if raw materials, semi-finished goods, and finished products are clearly distinguished, and if defective items are stored separately. Strongflex strictly adheres to its quality control system; products found to be non-compliant during production are remediated immediately if possible, or marked in red if not. Such defective items are never sold to customers at full price; instead, they are sold as seconds or sent for recycling.
Production Equipment and Processes: Check for the use of state-of-the-art braiding and spiral-winding equipment. Inspect semi-finished hoses—specifically the steel wire reinforcement layer—checking for joints and diameter uniformity to evaluate the manufacturing process and quality control standards. We measure and record the diameter at multiple points along every batch of braided or spiral-wound hose.
Quality Control Systems: Assess the robustness of quality control and product traceability (e.g., tracking production batches, raw materials, and production dates). Our factory employs a dual online and offline quality control system; every hose is assigned a unique “ID,” allowing for full traceability back to the specific production equipment, date, personnel, and batch.
Product Inspection: Ensure comprehensive quality inspections are conducted after production but before packaging. Verify specifications regarding working pressure and burst pressure, and confirm that pressure and impulse tests are performed using a well-equipped laboratory.
Actual Production Capacity and Order Fulfillment: Evaluate actual production capabilities based on the number of production lines, equipment operational status, and current order volume. Inquire about production scheduling, standard lead times, and the capacity to handle large-volume orders.
A factory visit is essential to truly assess the reliability of the workforce and determine whether the manufacturer is worthy of your orders.
The production process of hydraulic hoses involves many steps from material selection to final inspection. Hydraulic hoses are widely used in various mechanical equipment, strict control at every step of the production process is necessary to ensure the safety and reliability of hoses in application.
In addition
Strongflex can provide you with a wide range of hydraulic hoses, industrial hoses, and fittings in many materials, and if needed, hydraulic hose crimping machines and cutting machines can also be purchased by contacting us. Our products meet ISO 9001:2015 and industry quality standards. We have a professional production and sales team. We will strive to complete every step of the order, including the determination of product details, the selection of product raw materials, quality control in production, testing of finished products, transportation of packages, until you receive a satisfactory product.
Customer satisfaction is our primary goal, and our customers’ customers are also our service objects. We are committed to achieving the satisfaction of our service objects.