STECKO Fittings (Mining) – Threadless Plug-in Connectors

STECKO hydraulic fittings and connectors (P71 family) is a world standard for professional plug-in fittings designed for crimping onto hoses and creating high-pressure hydraulic connections. The STECKO system is characterized by the absence of a traditional thread – the plug-in part (male) is inserted directly into the socket and locked with a spring pin (split pin / U-clip). This solution allows for instant connection and disconnection of the hydraulic hose without the use of assembly wrenches.

Operating Principle and Design of the STECKO System

The STECKO system was created for work in the most demanding environments, such as underground mining, where time saving, safety, and resistance to mechanical damage are of key importance:

1. Instant pin assembly: After inserting the male end into the socket, a steel pin immobilizes the connection, preventing it from disconnecting under pressure or vibration.
2. Double seal (O-ring + PTFE): Tightness is ensured by an internal O-ring made of NBR rubber located in the plug-in part, supported by a back-up ring made of Teflon (PTFE), which protects the seal from extrusion under increased pressure.
3. Resistance to harsh conditions: Elements made of free-cutting steel protected by electro-galvanization guarantee long-term protection against corrosion, moisture, and dust contamination.

Technical Specifications of P71 Fittings

• Fitting family: P71 (STECKO) with one or two disassembly grooves
• Body material: Free-cutting steel protected by a zinc coating
• Sealing: NBR (O-ring) + PTFE Teflon (back-up ring)
• Working pressure: From 130 bar up to 450–530 bar (depending on the DN diameter)
• Hose compatibility: Designed for crimping on hydraulic hoses of type 2SN, 4SP, and 4SH (including on mining hoses with flame-retardant underground approval)
• Industry standards: Manufactured according to DIN 20043 and PN-G-32000 standards

Range of STECKO Connectors at the HYDRON Store

Our offer includes a full range of STECKO plug-in fitting components:

• P71 crimp fittings and ferrules: Dedicated for crimping on flexible hydraulic hoses.
• Plug-in connectors and adapters: Straight connectors, reduction connectors (e.g., DN10, DN12, DN19, DN25, DN32, DN51) and adapters for metric and BSP threads.
• Socket connectors, tees, and manifolds: 90° elbows and elements for expanding hydraulic lines.
• Pins (clamps / clips): Steel safety clamps in all sizes.
• STECKO mining shut-off valves (Type B): High-pressure ball valves with socket/plug connections with underground approval.

Application

STECKO connections are commonly used in underground mining (powered roof supports, shearers), forklifts, material handling machines, and heavy-duty power hydraulics, where reliability and immediate hose replacement count.

Frequently Asked Questions (FAQ)

How to correctly select the size of a STECKO connector?

The size is selected based on the nominal diameter DN (e.g., DN10, DN12, DN19/20, DN25, DN32, DN40, DN50/51). Measure the outer diameter of the plug-in part and check the markings on the old part, as variants close in size are not interchangeable.

Do STECKO connectors include seals?

Yes, the offered STECKO plug-in fittings and adapters are equipped with a complete, factory sealing kit (NBR O-ring + PTFE back-up ring) designed to work with mineral oils and HFA/HFB/HFC water-oil emulsions at temperatures from -40°C to +100°C.