Broomfields Marine Exhaust works directly with our customers to supply the correct exhaust expansion joints and flex connectors for their specific application. We stock a large inventory of expansion joints. Custom joint fabrication is always available.
MULTI-PLY BELLOWS VS CONVENTIONAL SINGLE PLY HOSE ADVANTAGES
INSTALLATION TIME– Easily handled as weight is less, due to shorter length, traverse adjustment can be made by hand.
Shorter Overall Length, Space Saving, Lighter Weight.
Turbulence and pressure drop are extremely low due to close pitch construction and length.
Low force is required to gain maximum axial traverse, example:
6” Multi-ply bellows: Axial spring rate lbs./inch = 133
6” Single wall hose: Axial spring rate lbs./inch = 222
The above example demonstrates the engine manufactures requirements that the loads on engine manifolds and turbochargers are to be reduced to the smallest force possible. The reduction in bending stresses obtained by using a “multi-ply bellows” reduces the force to compress or offset the unit, thus the loads directed to the manifold or turbo are reduced.
In some instances it is desirable to use a liner which, in its simplest form, is a tubular sleeve inside the flexible member. This serves two very important functions:
- The liner reduces the operating temperature of the flexible member thereby prolonging service life.
- The liner prevents flow velocity turbulence which could cause the flexible member to vibrate at its resonant frequency and cause premature failure.
It is recommended that the flex joint should have a liner if the flex joint is less than 4 to 6 diameters of the exhaust piping away from the manifold or turbo. This liner protects the inside of the convolution from being bombarded by hi heat carbon particles. Which at times have caused premature failure of the flex connection. These hi heat particles seem to break up as they go farther down the exhaust piping.
Flex joint should be mounted straight with no weight on it. You should be able remove the flex unit without the exhaust piping moving.
MULTI-PLY (BELLOWS) EXHAUST FLEX
Multi-ply Exhaust Expansion Joints, the answer to these demanding exhaust expansion joint applications. Engineered to overcome exhaust system piping motion and vibration.
Designed with prime power and marine exhaust systems in mind, the multi-ply expansion joint has proven itself in the field.
The multi-ply bellows is capable of absorbing vibration as well as the listed motions. This capability along with low spring rates reduces the loads on the system imposed by the single ply expansion joint.
Today’s modern engine package systems require the sophistication designed into the multi-ply expansion joint. Its ability to operate at a higher temperature over long periods of time insures minimum down time and greater system reliability.
The multi-ply bellows element (unlike flexible metal hose) is specifically engineered to exhaust applications. The bellows attachment welds are made at the bellows neck which is a low stress point, not at the I.D. or O.D. of a corrugation as on flex hose. The corrugation height is greater, improving flexibility and reducing the spring rates. Multi-ply construction provides a dampening effect on vibration instead of transmitting it to the system. Non standard overall expansion joints lengths can be provided.
Multi-ply bellows is constructed of plies of 321 stainless steel. Flanges are carbon steel with drilling conforming to A.N.S.I. 150#. Special flange drilling is available to match specific applications. Weld ends are standard wall carbon steel pipe. Flow liners can be provided as an option.
The Multi-ply with Vanstone flanges is available when flange hole alignment may be a problem.