What types of Storz couplings are there?

Storz couplings (also commonly known as Cam lock couplings or German quick couplings) are quick-connect couplings widely used in fire protection, water treatment, chemical, agricultural, and industrial fluid transportation fields due to their simple operation, reliable connection, and high interchangeability. They consist of two identical claw-type fittings that achieve a sealed connection simply by inserting and rotating (usually 120° or 90°), without the need for additional locking mechanisms, greatly improving efficiency and safety.

Classification of Storz Couplings

Although the basic design and working principle of Storz coupling are unified—that is, quick locking is achieved through claws (or ears) and corresponding cam structures—they can still be classified in various ways according to their connection form and materials to meet different fluid transportation needs.

1. Classification by Connection End (Most Common Type)

This is the most important classification method, determining how Storz couplings connect to other equipment or piping:

Storz Hose Coupling:

Applications: Used to directly connect Storz coupling to fire hoses, industrial hoses, or agricultural irrigation hoses.

Features: Typically includes a hose tail (shank), secured to the hose with a clamp or clip, and is a core component of fluid connection systems.

Storz Threaded Coupling:

Applications: Used to connect Storz couplings to the inlet and outlet of pipes, valves, or pumps with standard threads.

Types: Divided into female thread and male thread couplings. Common thread standards include BSP, NPT, etc. This type is key to enabling quick conversion and system integration.

Storz Blank Cap/Plug:

Applications: Used to seal unused Storz coupling outlets or hose ends to prevent fluid leakage or contaminants from entering the fluid system.

Features: Equipped with a sealing ring for reliable sealing performance.

2. Classification by Material

The corrosion resistance and durability of Storz couplings depend primarily on their manufacturing materials, which directly affect their application in specific media:

Aluminum Alloy Storz Couplings:

Features: Lightweight, cost-effective, and with good corrosion resistance.

Applications: Most commonly found in fire-fighting equipment, water treatment, and general industrial fluid transport.

Brass/Bronze Storz Couplings:

Features: High strength, corrosion resistance, high temperature resistance, and spark resistance.

Applications: Suitable for marine environments, the oil and gas industry, and applications requiring higher durability.

Stainless Steel Storz Couplings:

Features: Excellent chemical corrosion resistance and high strength.

Applications: Widely used in industries with extremely high requirements for hygiene and media compatibility, such as chemical, food processing, and pharmaceutical.

Storz couplings made of polypropylene (PP) or nylon and other plastics:

Features: Extremely lightweight, excellent chemical resistance, and low cost.

Applications: Agricultural irrigation, low-pressure water treatment, and the transport of certain specialty chemicals.

Specifications and Interchangeability

A key characteristic of Storz couplings is their interchangeability. Their specifications are not determined by pipe diameter, but by the lug spacing (or cam spacing). As long as the lug spacing is the same, Storz couplings from different manufacturers and with different end types (such as hose fittings and plugs) can be interconnected.

Common claw spacings include:

• 52 mm (D size, for DN25/DN32 hoses)
• 66 mm (C size, for DN38/DN50 hoses)
• 89 mm (B size, for DN65 hoses)
• 133 mm (A size, for DN100/DN110 hoses)
  
  

To select the appropriate Storz coupling, first determine the required size (claw spacing) to ensure interconnection. Secondly, based on the properties, pressure, and temperature of the conveyed medium, select the most suitable material (e.g., aluminum, stainless steel) and connection type (e.g., hose tail or thread). Whether for emergency fire connections or everyday industrial fluid control, Storz couplings are ideal for achieving efficient and safe connections.