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Johnson Type Centerpipes


Johnson Type Centerpipes

Radial Flow Reactor Internals: Vee Wire Scallop | Johnson Type Centerpipes
Wedge Wire Screen Filter, Johnson Screen Products Manufacturer

At present, recombination isomerization reactors generally have a Johnson type centerpipes inside.

The bottom of the reactor central mesh is in communication with the outlet of the reactor. When the reactor is in use, the reaction raw materials enter from the inlet at the top of the reactor, a series of reactions occur under the action of the catalyst, and the reaction products flow out from the outlet at the bottom of the reactor through the Johnson central screen tube.
Therefore, the central pipe is an important internal component in the recombination and isomerization reactor.
Its role is to balance the pressure drop inside the reactor with the ceramic balls and catalyst in the reactor, and filter out impurities such as the catalyst flowing out of the reaction product. Once the central tube is damaged, the entire system will be discontinued, causing great losses.

The central pipe produced by our company is manufactured by using patented technology combining laser cutting and composite welding. It has the characteristics of accurate structure size, high gap accuracy, high strength of screen welding joints, and no longitudinal welding seams.

Electromagnetic welding is a new welding concept that solves the problem of cracks in the longitudinal weld under high temperature working conditions caused by the traditional resistance welding process, which greatly improves the service life of the central tube.

Specification of the Johnson screen Centerpipe

Material: Stainless steel 304, 316, 316L, Inconel-600 (or as your need).
Structure: Cylindrical wedge wire screen tube + Cover plate + Bare tube
Profile wire (wedge wire): Continuous slotted structure, large opening area, not easy to block, strong structure.
Slot size: 0.25mm or as your need.
Relevant assy (bare tube, plate, nipple and so on) can be customized.
Application: Widely used in catalytic reforming, styrene, synthetic ammonia, propane dehydrogenation and other process units.


It has the advantages of simple structure, convenient installation, good filtering performance and strong bearing capacity.
It can support the weight of catalyst well when installed in the reactor, and it is not easy to block the net for long-term use, so it has a long service life.

Wedge Wire Reactor Central Tube For Catalytic Reforming Process

Catalytic reforming is an important process in oil refining and petrochemical industry, and the continuous reforming technology makes a revolutionary breakthrough in catalytic reforming technology.

The four in one continuous reforming reactor is the key equipment of the continuous catalytic reforming technology. There are various parts in the reactor, and the wedge wire central screen tube base is one of them.

If the perpendicularity of the central tube is not good, the catalyst distribution will be uneven, and the pressure drop and flow rate of oil and gas passing through the catalyst bed will be different, which will eventually affect the reaction effect.

The unified installation method is: use the crane to lift the base of the central pipe to the internal installation position of the equipment, and then adjust its levelness. During the installation, due to the deviation of levelness and verticality, it needs to be repeatedly installed and debugged, which is time-consuming and laborious, easy to make the internal parts collide and damage each other, and it is difficult to ensure the verticality of the central pipe.

Therefore, correct installation is particularly important.

We provide drawing design service for Johnson screen reactor center pipe.