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3406E & 3056 INDUSTRIAL ENGINE – Hose Clamps

Worm Drive Band Type Clamps

Illustration 1 g00910017
Table 1
Width (A) of Clamp     Torque for New Hose    
7.5 mm (0.3 inch) or greater     1.4 ± 0.3 N·m (12 ± 3 lb in)    
12 mm (0.5 inch) or greater     4.5 ± 0.7 N·m (40 ± 6 lb in)    
14 mm (0.6 inch) or greater     7.5 ± 1 N·m (66 ± 9 lb in)    
Width (A) of Clamp     Torque for Reused Hose (1)    
7.5 mm (0.3 inch) or greater     0.8 ± 0.3 N·m (7 ± 3 lb in)    
12 mm (0.5 inch) or greater     3.0 ± 0.5 N·m (27 ± 4 lb in)    
14 mm (0.6 inch) or greater     4.5 ± 0.7 N·m (40 ± 6 lb in)    
( 1 ) Use this value when the hose is reused. The clamp may be new or reused.

Constant Torque Hose Clamps

Use a constant torque hose clamp in place of any worm drive band type clamp. Ensure that the constant torque hose clamp is the same size as the worm drive band type clamp. Due to extreme temperature changes, the hose will heat set. Heat setting can cause worm drive band type clamps to loosen. Loose hose clamps can result in leaks. There have been reports of component failures that have been caused by worm drive band type clamps that have loosened. The constant torque hose clamp will help prevent these failures.

Illustration 2 g03076961

(1) Constant Torque Hose Clamp (Belleville Washer)

(2) Constant Torque Hose Clamp (Tee bolt and Spring)

Use a torque wrench for proper installation of all constant torque hose clamps. There are two types of constant torque hose clamps: Belleville washer (1) and Tee bolt and spring (2)

When the constant torque hose clamp (Belleville washer) (1) is assembled correctly, the Belleville washers (1A) are nearly collapsed flat. The proper torque for screw (1B) is based on the diameter (B) of the clamp. Refer to the following table for the correct torque.

Table 2
Diameter (B)     Standard Torque    
Up to
50.8 mm (2 inch)    		 7.5 ± 1 N·m (65 ± 10 lb in)    
Greater than
50.8 mm (2 inch)    		 11 ± 1 N·m (95 ± 10 lb in)    

The correct torque for the constant torque hose clamp (tee bolt and spring) (2) is 7.5 ± 1 N·m (65 ± 10 lb in).