In scenarios such as hydraulic systems and car modifications, the question "Can rubber hoses be paired with AN connectors?" is a common query. The AN connector (Army-Navy connector) is renowned for its high precision and strong sealing performance, while rubber hoses are favored for their good flexibility and low cost. In fact, as long as the right method is chosen, the two can work together stably. Now, let's break down the key points.

Ⅰ. let's take a look at the "three essential elements of adaptation"

The AN connector has a unified standard: the threads are marked as "AN + number" (for example, AN6 corresponds to an inner diameter of 9.5mm), sealed by a 37° conical surface or O-ring, and can withstand high pressure and vibration of 3000-6000 PSI. The rubber hose depends on the inner diameter, wall thickness, and temperature and pressure resistance. Common materials include oil-resistant nitrile rubber and weather-resistant EPDM rubber, and the working pressure is usually between 1000-3000 PSI.

The compatibility of the two components needs to meet three conditions: Firstly, the dimensions must align. The inner diameter of the AN connector must be exactly the same as the inner diameter of the hose, with any deviation exceeding 0.5mm causing leakage; Secondly, the pressure must match. The rated pressure of the hose must be ≥ the actual pressure of the system to prevent explosion; Thirdly, the materials must be compatible. The oil, coolant, etc. being transported must simultaneously meet the corrosion resistance requirements of the hose and the sealing components of the connector, for example, the nitrile hose should not come into contact with strong acids.

II. 3 Simple Steps for Correct Installation, Avoiding Common Pitfalls

The installation was incorrect, prone to leakage and detachment. Following the standardized procedures would be more reliable.

The first step  in pre-processing the hose: Use a special cutting tool to make a vertical cut. Do not use scissors or saws, as this will result in an uneven cut, rough edges, and damage to the sealing surface of the joint. Then, use compressed air to blow away the debris inside the hose. When transporting hydraulic oil or other precision media, alcohol should be used to wipe the inner wall. If the wall thickness exceeds 3mm, use an expansion tool to expand the inner diameter of the port by 1mm to facilitate the insertion of the connector.

Step 2: Select the correct AN connector type: The compression type is suitable for high pressure (＞3000 PSI), requiring a special machine for compression and providing a tight seal but cannot be disassembled; the push-on type does not require tools and is fixed by friction, suitable for medium and low pressure (＜2000 PSI), easy to disassemble, suitable for systems that require frequent maintenance; the threaded type requires machining internal threads at the hose end and is only suitable for pipes with a wall thickness of over 5mm, mostly used for fixing pipelines. For example, for car engine oil pipes, select the AN6/AN8 compression type connector with nitrile rubber hose, which can withstand engine temperatures of 80-120°C and vibrations.

The third step - standard installation: The connector should be inserted to the marking line (usually 3-5mm). If it is too shallow, it won't be secure; if it is too deep, it will block the hole. For threaded connectors, wrap 3-5 turns of the pre-stretched tape (do not insert it into the pipe) or apply an anaerobic sealant; after manual tightening, use a wrench to tighten another 1/4 - 1/2 turn. Over-tightening will cause the hose to deform and leak. For AN6 connectors, it is recommended to use a torque wrench with a setting of 15-20N・m.

III. Avoiding 3 Common Misunderstandings

When actually using it, some pitfalls need to be avoided. In low-temperature environments (below -20℃), ordinary hoses will become rigid and lose elasticity. In such cases, it is necessary to replace them with chloroprene rubber hoses that can withstand -40℃. Before installation, preheat them to above 0℃ to prevent cracking. In scenarios with strong vibrations (such as in construction machinery), in addition to selecting compression-type joints, you can also wrap the joint with shock-absorbing tape. Install fixed brackets every 30cm and use a wrench to retighten once a month.

Don't overlook the issue of compatibility with different media either. For example, using ordinary natural rubber hoses for diesel transportation will cause the hoses to expand and leak. You need to check the material of the joint sealing parts and refer to the "media compatibility table" provided by the hose manufacturer. For transporting food-grade liquids, choose food-grade AN joints with polished inner walls and silicone hoses, which comply with FDA standards.

Ⅳ. Simple Maintenance to Extend Lifespan

After installation, conduct a pressure test first: introduce a medium at 1.2 times the rated pressure and maintain it for 30 minutes. Apply soapy water to the sealing surfaces and bubbles indicate leakage. Regularly check the hoses for aging and cracking every week. Apply anti-rust oil to the metal joints to prevent rust. The rubber hoses typically last 2-3 years. Even if they are not damaged, replace them regularly. When replacing, also inspect the sealing surfaces of the joints to see if there are any scratches or deformations. If so, replace them together.

In fact, installing AN connectors on rubber hoses is not difficult. The key lies in accurately matching parameters, choosing the right type, and following proper procedures. Whether it's repairing equipment or modifying vehicles, don't blindly pursue high specifications. By selecting the appropriate combination based on pressure, temperature, and medium, you can ensure performance while controlling costs.