Friday, 22 March 2019 07:30

Installation Instructions of Expansion Joint

Written by
 final-prod02 News - Flexible Metal Hose Manufacturer | Hengshui Ruiming
Installation and maintenance instructions for one-and multi-layer expansion joints.
The piping system must be adecuadamenre anchored and guided to limit the pipe movements that the expansion board must absorb. View the space and anchorage requirements of the EJMA standard.
Ensure that the entire pipe is supported so that the expansion joint does not hold this load.
The operating conditions must be within the limits provided in the catalogue and/or drawing.
Install the expansion joints with the face-to-face neutral dimensions, as shown in the sent drawing.
If the expansion joint is to be installed with an initial misalignment, the compression and/or expansion movements, in addition to the maximum permissible movements, are reduced depending on this initial deflection.
Caution: Expansion joints are not designed to react to torque or torsional movements (in a plane perpendicular to the centerline). It is necessary to ensure that there are no such conditions in the system design or for lack of alignment of the installation.
Restrictors can be welded or threaded at the factory to ensure installation at the correct length and alignment. Whenever it is possible to leave these restrictions in place during installation. However, they should be removed before operating the system.
Braces or control rods may be included in some expansion joints. They are designed to
(1) limit the over-travel
(2) to absorb the pressure of the expansion joint in the event of a defect of the main anchor
(3) to absorb the design pressure of the lateral movement system and there are no anchors within it.
Note: The system design should be carefully checked for proper use of these bars as they may restrict the movements of the expansion board if used incorrectly.
Warning: Provide protection to the thin wall of expansion joint ripples during removal of shipping restrictions whether they are being cut or ground. Sparks can damage the ripples.
Some designs include flow lines or sleeves which extend through the connector gap. A mark must be included on the outer surface of the expansion board to indicate the direction of the design flow. The expansion joint should be installed as shown. If there is any possibility of inverse flow or entrapment of material behind the liner, the design engineer or a ruiming representative must be consulted before operating the system.
All expansion joints are tested at 1.5 times the operating design pressure. System tests should not exceed this pressure.
Monday, 18 March 2019 11:13

Glossary of Terms

Written by

Glossary of Terms_Flexible Metal Hose

 Sizes News - Flexible Metal Hose Manufacturer | Hengshui Ruiming
Angular rotation: flexion around the longitudinal centerline of the expansion joint.
Axial extension: Extension of bellows length due to pipe contraction when piping system is properly anchored.
Axial compression: Compression of the bellows length due to expansion of the piping when the piping system is properly anchored.
Bellows: The flexible element of an expansion joint consisting of one or more rebates.
Expansion Joint Bellows: Any device containing one or more bellows used to absorb direction changes, such as those caused by the expansion or thermal contraction of a pipe, conduit, or container.
Concurrent movement: simultaneous axial, lateral and angular movement.
Control bar: Devices connected to the expansion board with the function of distributing the movement between the two bellows of a universal joint.
Convolution or corrugation: the smallest flexible unit in the bellows. The total movement of a bellow is proportional to the number of rebates.
Cycle: A cycle is a full motion from the starting position to the operating position and vice versa.
Life cycle: Also known as fatigue life expectancy, which is affected by several factors including (but more limited to): service pressure, operating temperature, bellows materials and bellows design or profile. The change to any of these factors changes the life cycle.
Directional Anchor: A directional or sliding anchor anchor is designed to absorb loads in one direction while allowing movement in another. It can be a primary or intermediate anchorage, depending on the application considered. When designing a directional anchor, an effort must be made to minimize friction between moving or sliding parts, as it will reduce the load on the piping and equipment, and ensure proper operation of the anchor.
Outer cover: Expansion joints require careful handling; They must be protected from any impact, solder splashes, etc. Before installing an expansion joint, care should be taken to prevent any foreign material from being found in the convolutions. It is appropriate to install a metal cover on the flanges to protect the convolutions and then cover with insulating material.
Flow liner: It is installed in the inlet hole of the expansion joint to protect the bellows from erosion damage due to abrasive media or resonant vibration by turbulent flow and excessive velocities. An arrow should be placed indicating the direction of flow on the outside of the expansion joint.
Intermediate Anchor: A device that divides a pipe into individual expansion sections that contain multiple expansion devices of the same pipe size. This anchor must be designed to withstand the forces and movements imposed by each section of the pipeline to which it is attached. In the case of a pipe section containing one or more bellows units, these forces will consist of forces and/or moments necessary to deflect the bellows unit plus the frictional forces due to the pipe moving over its guides. The thrust pressure is assimilated by other anchors or bellows unit devices such as limiting bars, tie rods, limiting hinges, etc.
Lateral displacement: movement that is perpendicular to the plane of the pipe and parallel to the remaining accessories of the expansion joint.
Limiting bar: Devices with the main function of restricting the range of motion of the bellows. They are designed to prevent over-extension or over-compression of the bellows and at the same time restrict the total thrust pressure in case of failure of the main anchor.
Primary anchor: A primary anchor is installed in any of the following locations on a piping system containing one or more bellows:
In the direction of flow change
Between two bellows units of different sizes and installed in the same straight section
At the entrance of a lateral branch of the main line
When a pressure reducing valve is installed on a pipe segment between two bellows units on the clogged end of the pipe.
A primary anchor must be designed to withstand the forces and times imposed by each of the pipe sections it is attached to. In the case of a pipe section containing an unrestricted bellows, these will consist of the thrust pressure, the force required to deflect the bellows unit and the frictional force due to the movement of the pipe over its guides.
Pipe Alignment Guide: It is a form of sleeve fixed to a rigid part of the installation, which allows the pipe to move freely in a single direction, ie

Friday, 15 March 2019 01:13

Post-Installation Instructions

Written by

installation of expansion joint

Are the anchors, guides and supports installed according to the system design?

Is the expansion board installed in the right place?

Is the expansion board installed in the correct flow direction? (if liner is required) have the shipping restrictions been removed?

Are all the guides, supports and expansion joints free to allow for the required movements?

Has the expansion board been damaged during operation and installation?

Is the expansion board installed correctly:?

Installation length and correct alignment

Free of other objects enough to allow design movements

Maintenance: Expansion joints do not require any maintenance other than routine cleaning and/or paint to prevent external corrosion. If the expansion board is being used in a system where liquid can be formed during a stoppage and operate at high temperature where the liquid can be converted into vapor, the expansion joint must be drained before the start-up , to avoid flickering and the water hammer.

Monday, 11 March 2019 09:27

When to use Metal Hose

Written by

When to use Metal Hose:


There are many different types of hose available on the market. They include metal, rubber, composite, PTFE and fabric. The decision of which hose type to buy depends on the application for which the hose is being used. Generally, there are eight factors that should alert you to consider using metal hose:

1. Temperature Extremes - If either the temperature of the media going through the hose or the surrounding atmospheric temperature is very cold or hot, metal may be the only material that can withstand the temperature extremes.


2. Chemical Compatibility - Metal hose can handle a wider variety of chemicals than most of the other hose types. If the hose will be exposed to aggressive chemicals (either internally or externally), metal hose should be considered.


3. Permeation Concerns - Non-metal hose is susceptible to having gases permeate through the hose wall and into the atmosphere. Metal hose, on the other hand, does not allow permeation. If containing the gases inside the hose is important, metal hose may be required.


4. Potential for Catastrophic Failure - When a metal hose fails, it usually develops small holes or cracks. Other hose types tend to develop larger cracks or come apart completely. If a sudden failure of the hose can be catastrophic, a metal hose may help minimize the effects of a failure by leaking product at a slower rate.


5. Abrasion and Overbending Concerns - To prevent abrasion and overbending, a metal hose can be used as a protective cover over wires or even other hoses.


6. Fire Safety - Other hose types will melt when exposed to fire while metal hose maintains its integrity up to 1200o F.


7. Achieving Full Vacuum - Under full vacuum, metal hose maintains its shape while other hose types may collapse.


8. Flexibility in Fitting Configuration - Virtually any type of fitting can be attached to metal hose while other hose types require special shanks and collars.


Types of Metal Hose:


Corrugated Metal Hose - Corrugated metal hose can handle high pressures and is gas tight. It is excellent for gas and liquid transfers.

flexible-metal-hose-3 News - Flexible Metal Hose Manufacturer | Hengshui Ruiming


Stripwound Metal Hose - Stripwound metal hose, although not gas tight, is rugged, making it excellent for use as a guard, an open-ended exhaust hose, and for the transfer of dry bulk materials.

stripwound_-metal-hose News - Flexible Metal Hose Manufacturer | Hengshui Ruiming

Saturday, 10 September 2016 01:35

Space Desk Workspace Coworking

Saturday, 10 September 2016 00:38

Pink and Gray Telephone

Written by

Lorem Ipsum is simply dummy text of the printing and typesetting industry. Lorem Ipsum has been the industry's standard dummy text ever since the 1500s, when an unknown printer took a galley of type and scrambled it to make a type specimen book. It has survived not only five centuries, but also the leap into electronic typesetting, remaining essentially unchanged.

Contrary to popular belief, Lorem Ipsum is not simply random text. It has roots in a piece of classical Latin literature from 45 BC, making it over 2000 years old. Richard McClintock, a Latin professor at Hampden-Sydney College in Virginia, looked up one of the more obscure Latin words, consectetur, from a Lorem Ipsum passage, and going through the cites of the word in classical literature, discovered the undoubtable source.

All the Lorem Ipsum generators on the Internet tend to repeat predefined chunks as necessary, making this the first true generator on the Internet. It uses a dictionary of over 200 Latin words, combined with a handful of model sentence structures, to generate Lorem Ipsum which looks reasonable.

There are many variations of passages of Lorem Ipsum available, but the majority have suffered alteration in some form, by injected humour, or randomised words which don't look even slightly believable. If you are going to use a passage of Lorem Ipsum, you need to be sure there isn't anything embarrassing hidden in the middle of text.