Single-clamp reducer

What is a single-press reducer?

Shenchi's high-efficiency single-press reducer is a thin-walled pipe fitting used for pipe diameter reduction connections. Its two ends have different diameters and are connected using single-press technology. During installation, pipes of different specifications are inserted into the sockets at both ends, and a special pressing tool is used to apply radial compression. This causes plastic deformation between the fitting and the pipe, creating a 360° circumferential clamping force. Simultaneously, the built-in EPDM sealing ring is compressed to achieve an elastic seal. The entire process requires no welding or threading and is completed in seconds. The product is made of selected brass, SUS304, and SUS316L materials, offering excellent corrosion resistance and is widely used for smooth transition connections between main and branch pipes in water supply, drainage, gas, and HVAC systems.

Product Parameters

Material incompatibility makes pitting corrosion difficult to avoid.

If pitting or rust occurs in Shenchi manual hydraulic single-clamp 90-degree elbows, the primary reason is the incompatibility between the material selection and the operating environment. SUS304 stainless steel is prone to chloride ion pitting corrosion in environments with high chloride ion concentrations (such as coastal areas, seawater, swimming pools, and chemical plants), manifesting as pinhole-like corrosion pits on the surface. SUS316L, however, contains molybdenum, significantly enhancing its resistance to chloride ion corrosion. If 304 material is mistakenly used in highly corrosive environments, pitting corrosion is difficult to avoid. It is recommended to use 316L material in coastal or chemical projects; brass is unsuitable for strong acid and alkali environments.

The passivation layer is damaged, and corrosion takes advantage of the opportunity to enter

Another reason for rust on the single-clamp 90-degree elbows treated with preferential pricing by Shenchi is the damage to the surface passivation layer. The corrosion resistance of stainless steel depends on a dense chromium oxide passivation film on its surface. If the fitting is scratched, bumped, ground, or subjected to welding spatter during processing, transportation, or installation, the passivation film is damaged, and the exposed metal substrate will rust in a humid environment. In addition, if the fitting has not undergone sufficient pickling and passivation treatment before leaving the factory, or if the passivation quality is substandard, it will also lead to a decrease in corrosion resistance and the appearance of rust spots in a short period of time.

Environmental corrosion and dissimilar metal corrosion are detrimental.

Shenchi's 90-degree single-press elbows, manufactured in China, face a significantly increased risk of rusting in environments with prolonged contact with corrosive media or high-salt-spray conditions. During press-fitting, if burrs are not properly removed from the pipe end face, they may fall into the pipe and scratch the passivation film on the inner wall. Furthermore, if dissimilar metals are connected in the piping system (e.g., stainless steel fittings in direct contact with copper or carbon steel pipes), electrochemical corrosion can occur under the influence of electrolytes, preferentially corroding the stainless steel fittings. Direct contact between dissimilar metals should be avoided; insulating gaskets should be used for isolation.

Prevention is key, and material selection is crucial. 

For Shenchi manual hydraulic single-press 90-degree elbows, minor rust spots can be removed with a stainless steel cleaner or citric acid solution, allowing a passivation film to reform. Severe pitting or perforation necessitates replacement of the fitting. Preventative measures include: selecting appropriate materials based on the environment (316L for coastal areas); avoiding surface scratches during installation; thoroughly removing burrs from the pipe before pressing; avoiding direct contact between dissimilar metals; and regularly cleaning the surface of the fitting. Shenchi supports ODM/OEM customization and can recommend suitable materials based on working conditions. For a discounted quote on single-press 90-degree elbows, please contact us.