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The ZLG Banjo fitting utilizes a combination of metal to metal and elastomeric (O-ring) seals instead of relying on soft metallic washers. See also answer #2.

There are two metal-to-metal seals in every ZLG Banjo fitting assembly. These banjos are designed to utilize the taper that is part of the SAE J1126 and ISO 6149 port configurations. The first tapered metal-to-metal seal is located under the head of the ZLG Banjo bolt head. The angle of the taper cooperates with the taper in the port that is located on the top of the ZLG Banjo body.

The second tapered metal-to-metal seal is part of the bottom of the ZLG Banjo body through which the Banjo bolt will pass. The taper of this seal will engage with the taper in the port of the banjo host component. The taper at the top of the Banjo bolt and the taper at the bottom of the Banjo body engage in their respective ports and utilize the mechanical advantages of the tapers.

The metal-to-metal engagements minimize gaps that occur due to axial movement associated with internal pressurization. Each engagement is several thousandths of an inch. This generates high unit loading between mating components during application of assembly torque.

These design features combine to produce high integrity metal-to-metal interfaces.

Elastomeric seals (O-rings) act as “belt and suspenders” back ups for the metal-to-metal seals.

There are two O-rings in each ZLG Banjo fitting assembly. Both are positioned in machined pockets whose cross sectional areas are greater than the cross sectional areas of the elastomers they contain.

The first O-ring is located immediately below the taper under the head of the banjo bolt. It is installed on the banjo bolt before the bolt is inserted in the banjo body.

The second O-ring is installed on the lower part of the banjo bolt after the bolt has been inserted through the banjo body. This O-ring is seated on an undercut on the bolt, immediately in front of the taper on the bottom side of the banjo body.

The ZLG Banjo bolt and body assembly is held in place by swaging the skirt of the banjo body to form the lower taper. The tightening of the ZLG Banjo bolt into the host port engages both metal-to-metal seals and allows the two elastomeric seals to be in their proper positions, reacting dynamically to any pressure differential across the interface.

It is important to note that standard banjos have four leak-paths, one each side of the metallic compression washers used to seal them. The ZLG Banjo, however, only has two leak-paths, each sealed with metal-to-metal and elastomeric (O-ring) seals.

See answer #2 above.

Those sizes that will accept the SAE J1926 and ISO 6149 port configurations.

Standard Hydraulic Industry manufacturing tolerances.

Commercially available (predominantly metric) sizes.

70 durometer material is used because its relative flexibility allows it to respond to the pressures that may occur during operational service. The elastomer can move dynamically to fill the leak path.

Any material that is commercially available may be used with the ZLG Banjo fitting. The type of material to be used is determined by the end user and application parameters.

SAE J1926 and ISO 6149 as well as special ports unique to customers’ existing requirements. For the ZLG Banjo system to function, the taper at the mouth of the port is a necessary feature.

The body is designed and machined to accommodate brazed components to form elbows, tees and crosses, and configured to accept hose or tube.

A. Banjo bodies - Coated low carbon steel, stainless steel, brass or aluminium.

B. Banjo bolts - Coated low carbon steel, stainless steel, brass or aluminium.

C. Tube material - Stainless steel, low-carbon steel, aluminium (with crimp-on attachment).

D. Port material - Cast steel, cast iron, low carbon steel, aluminum (cast or extruded).

The ZLG Banjo fittings may removed and reinstalled repeatedly. The actual number of times may be determined by specific application testing. However, ten reseals metal-to-metal are a proven capability on existing production banjo assemblies.

The standard range of banjos (-4 to -10 and -6mm to -16mm) is designed to resist 6,000psi; however, assemblies can be specifically designed to meet customers' specific pressure and environmental requirements.

Low pressures can be as difficult as higher pressures to seal due to the effects of vibration and temperature variations. The ZLG Banjo fitting functions as effectively in these conditions as it does at high pressures.

To replace the metallic washer style banjo fitting assemblies that may be leaking. Also to replace SAE and ISO adjustable elbows, tees etc., where simple assembly and tight environments dictate a better answer. Typical applications include fuel rails, diesel fuel supply lines, hydraulic pump and valve assemblies, oil cooler lines, lubrication lines and brake assemblies (particularly at the calliper).

When the male tapers on each component engage with the tapers in their respective ports, they create a holding effect like the Morse taper. The tighter the engagement, the stronger the holding ability of the mating tapers, and the greater the resistance to separation. By using the elastic memory inherent in most metals, the ZLG Banjo offers exceptional resistance to vibration, pressure spikes, thermal transients and impact shock. By combining metal-to-metal seals with elastomeric (O-ring) back-up seals, the ZLG Banjo is the most robust banjo assembly available.