Tag Archives: hydraulic pipe

China Good quality Stainless Steel 316L/304 Threaded Pipe Fittings, Coupling 3 in. Stainless Steel for Rigid Conduit, Stainless Steel Hydraulic Fittings

Product Description


Stainless steel and carbon steel thread pipe nipples. Welding nipple, barrel nipple, close nipple, merchant coupling, welding coupling, kc nipple, hose nipple and so on. Natural surface, sandblasting, galvanized (hot dip galvanized, cold/electrical galvanize) or polishing finished. BSPP, BSPT, NPT, DIN thread, male and female thread. All materials, Stainless steel 201, Stainless steel 304, Stainless steel 316/316l, carbon steel, weld and seamless pipe. All thickness, sch10, sch20, sch40, sch80, sch160, XH, XXH and so on, pressure 150lb and 3000psi.






Welding nipple, barrel nipple, close nipple, merchant coupling, welding coupling, kc nipple, hose nipple

 BSPP, BSPT, NPT, DIN thread, male and female thread

Natural surface, sandblasting, galvanized (hot dip galvanized, cold/electrical galvanize) or polishing finished.

Stainless steel 201, Stainless steel 304, Stainless steel 316/316l, carbon steel, weld and seamless

thickness, sch10, sch20, sch40, sch80, sch160, XH, XXH and so on, pressure 150lb and 3000psi.


Q: Are you trading company or manufacturer ?


A: We are manufacture.


Q:   What’s your MOQ ?

A: MOQ is 1000 usually. But MOQ of each product is different. 

QCan I get a sample for testing ?

A: Yes, we can provide you a sample for reference, but you may pay for the sample and shipping fee. 

Q: Can you provide OEM/ODM service?

A: Sure, we are ready to meet all your demands!

Q:  Can I print my logo on the products ?

A: Yes, we can print your logo on the products as you required.

Q: What’s the lead time?

A: It will be 1-5 days for sample and 2-12 days for bulk order, it depends on your required.

Q: What’s the payment term?

A: We accept T/T, western union, L/C and Trade Assurance. For bulk order by T/T and Western Union, we will require 30% deposit first and 70% balance before delivery.

rigid coupling

How Does a Rigid Coupling Protect Connected Equipment from Shock Loads and Vibrations?

Rigid couplings play a crucial role in protecting connected equipment from shock loads and vibrations by providing a direct and rigid connection between the shafts. The design and properties of rigid couplings contribute to their ability to mitigate the impact of shock loads and vibrations in the following ways:

High Stiffness: Rigid couplings are constructed from materials with high stiffness, such as steel or aluminum. This high stiffness allows them to resist deformation and bending under load, ensuring that the coupling remains stable and maintains its shape. As a result, the shock loads and vibrations are not amplified or transferred to the connected equipment.

Immediate Torque Transmission: Rigid couplings provide immediate torque transmission between the shafts without any backlash or play. When the connected machinery experiences a sudden shock load, the rigid coupling effectively transfers the torque to the other side of the coupling without delay. This rapid and precise torque transfer prevents the shock load from causing misalignment or damaging the equipment.

Elimination of Damping: Unlike flexible couplings, which can dampen vibrations to some extent, rigid couplings do not have any damping properties. While damping can be beneficial in certain applications, it can also allow vibrations to persist, potentially affecting the performance and reliability of the connected equipment. Rigid couplings do not introduce any additional damping, ensuring that the vibrations are not prolonged.

Stable Connection: Rigid couplings create a stable and unyielding connection between the shafts, limiting any relative movement. This stability prevents the propagation of vibrations from one shaft to another, reducing the potential for resonance and vibration amplification.

Minimal Maintenance: Rigid couplings require minimal maintenance due to their simple and durable design. Unlike flexible couplings that may have wear-prone elements, rigid couplings do not have parts that need regular replacement. This reliability and low maintenance contribute to their ability to provide continuous protection against shock loads and vibrations.

In applications where shock loads and vibrations are prevalent, using a rigid coupling can help protect critical machinery and components from damage and premature failure. By providing a rigid and immediate torque transmission, rigid couplings effectively isolate the connected equipment from the harmful effects of shock loads and vibrations, ensuring smooth operation and enhanced reliability.

rigid coupling

What Industries Commonly Use Rigid Couplings for Power Transmission?

Rigid couplings are widely used in various industries for power transmission applications that require a solid and reliable connection between rotating shafts. Some of the industries that commonly utilize rigid couplings include:

  • Manufacturing: In the manufacturing industry, rigid couplings are employed in a wide range of equipment, such as conveyors, mixers, pumps, compressors, and machine tools. These couplings ensure precise power transmission and alignment, making them ideal for maintaining accuracy in manufacturing processes.
  • Material Handling: Material handling equipment, including cranes, hoists, and elevators, often rely on rigid couplings to transfer power between shafts efficiently. Rigid couplings provide a robust connection that can handle the heavy loads and continuous operation common in material handling applications.
  • Automotive: The automotive industry employs rigid couplings in various automotive systems, including drive shafts, transmissions, and steering systems. Rigid couplings contribute to the overall performance and reliability of these components, ensuring smooth power transfer and minimizing vibration.
  • Mining and Construction: In the mining and construction industries, rugged and durable power transmission components are crucial. Rigid couplings are used in equipment like crushers, mills, and heavy-duty conveyors, where they can withstand the harsh conditions and heavy loads commonly found in these applications.
  • Oil and Gas: The oil and gas industry often utilizes rigid couplings in pumps, compressors, and drilling equipment. Rigid couplings offer consistent and dependable power transmission, which is essential for critical operations in this sector.
  • Marine: In marine applications, such as ship propulsion systems and marine pumps, rigid couplings are used to transmit power between the ship’s engine and various equipment. They can handle the dynamic forces and vibrations encountered in marine environments.
  • Aerospace: In aerospace applications, where precision and reliability are paramount, rigid couplings play a role in power transmission between various aircraft components.

Rigid couplings are chosen in these industries for their ability to maintain shaft alignment, resist misalignment, and provide a backlash-free connection. Their robust construction and simple design make them suitable for high torque and high-speed applications, where precision and efficiency are crucial.

rigid coupling

Advantages of Using Rigid Couplings in Mechanical Systems:

Rigid couplings offer several advantages when used in mechanical systems. These advantages make them a preferred choice in certain applications where precise alignment and high torque transmission are essential. Here are the key advantages of using rigid couplings:

  • 1. High Torque Transmission: Rigid couplings are designed to handle high torque and power transmission without any loss due to flexibility. They provide a direct and solid connection between shafts, allowing for efficient transfer of rotational motion.
  • 2. Precise Alignment: Rigid couplings maintain precise alignment between connected shafts. When installed correctly, they ensure that the two shafts are perfectly aligned, which is crucial for applications where accurate positioning and synchronization are required.
  • 3. Synchronous Rotation: The rigid connection provided by these couplings enables synchronous rotation of the connected shafts. This is particularly important in applications where components must move in precise coordination with each other.
  • 4. Simple Design: Rigid couplings have a straightforward design with minimal moving parts. This simplicity makes them easy to install and maintain, reducing the chances of mechanical failure.
  • 5. Cost-Effective: Compared to some other coupling types, rigid couplings are generally more cost-effective. Their simple design and robust construction contribute to their affordability.
  • 6. High Strength and Durability: Rigid couplings are typically made from strong and durable materials such as steel, stainless steel, or aluminum. These materials can withstand heavy loads and provide long-lasting performance in demanding applications.

Rigid couplings are commonly used in various industries and applications, including high-precision machinery, robotics, automation systems, precision motion control, and machine tools. They are especially beneficial in scenarios where misalignment needs to be minimized or avoided altogether.

It’s important to note that while rigid couplings offer these advantages, they are not suitable for applications where shaft misalignment or shock absorption is required. In such cases, flexible couplings or other specialized coupling types may be more appropriate.

China Good quality Stainless Steel 316L/304 Threaded Pipe Fittings, Coupling 3 in. Stainless Steel for Rigid Conduit, Stainless Steel Hydraulic Fittings  China Good quality Stainless Steel 316L/304 Threaded Pipe Fittings, Coupling 3 in. Stainless Steel for Rigid Conduit, Stainless Steel Hydraulic Fittings
editor by CX 2023-11-16

China Good quality CZPT Precision Excavator Hydraulic Pump Coupling to Engine Flywheel Eh70 coupling pipe

Product Description

YNF Precision Excavator Hydraulic Pump Coupling To Engine Flywheel EH70


Basic information:


Material Genuine Material
Feature One-stop Shopping Experience
Packaging Details Plastic bag, Carton
Mass Production Booking
Performance Power Transmission
Connection Shaft/Spline/Straight
MOQ No Limited
Available In stock
Type Engine Parts

Product show as below:

 About us:

specialized in:

couplings, rubber mounts, gera parts, hydraulic seals and seal kits for hydraulic hammers, rock breakers, hydraulic excavators,wheel loaders, and JCB badkhoe loaders.


And, Our company also supply:

Engine parts, hydraulic piston pump and hydraulic travel motor, Swing motor assembly and hydraulic component parts, electric parts, etc. Hydraulic hammer breaker parts with piston, cylinder, chisel, through bolt, side bolt, top bush, front head bushing,accumlator, valve, etc.

We always try our best for all our customers and make it better and better. Welcome!



After-sales Service: Online Service
Warranty: Six Months
Application: Excavator
Certification: CE
Condition: New
Flexible or Rigid: Flexible


What Is a Coupling?

A coupling is a device used to connect two shafts. It transmits power between them and allows for some misalignment or end movement. There are several types of couplings. The most common ones are gear couplings and planetary couplings. However, there are many others as well.

Transfer of energy

Energy coupling is a process by which two biological reactions are linked by sharing energy. The energy released during one reaction can be used to drive the second. It is a very useful mechanism that synchronizes two biological systems. All cells have two types of reactions, exergonic and endergonic, and they are connected through energy coupling.
This process is important for a number of reasons. The first is that it allows the exchange of electrons and their energy. In a single molecule, this energy transfer involves the exchange of two electrons of different energy and spin. This exchange occurs because of the overlap interaction of two MOs.
Secondly, it is possible to achieve quadratic coupling. This is a phenomenon that occurs in circular membrane resonators when the system is statically deflected. This phenomenon has been gaining a great deal of interest as a mechanism for stronger coupling. If this mechanism is employed in a physical system, energy can be transferred on a nanometer scale.
The magnetic field is another important factor that affects the exchange of energy between semiconductor QWs. A strong magnetic field controls the strength of the coupling and the energy order of the exciton. The magnetic field can also influence the direction of polariton-mediated energy transfer. This mechanism is very promising for controlling the routing of excitation in a semiconductor.


Couplings play a variety of functions, including transferring power, compensating for misalignment, and absorbing shock. These functions depend on the type of shaft being coupled. There are four basic types: angular, parallel, and symmetrical. In many cases, coupling is necessary to accommodate misalignment.
Couplings are mechanical devices that join two rotating pieces of equipment. They are used to transfer power and allow for a small degree of end-to-end misalignment. This allows them to be used in many different applications, such as the transmission from the gearbox to the differential in an automobile. In addition, couplings can be used to transfer power to spindles.


There are two main types of couplings: rigid and flexible. Rigid couplings are designed to prevent relative motion between the two shafts and are suitable for applications where precise alignment is required. However, high stresses in the case of significant misalignment can cause early failure of the coupling. Flexible couplings, on the other hand, allow for misalignment and allow for torque transmission.
A software application may exhibit different types of coupling. The first type involves the use of data. This means that one module may use data from another module for its operation. A good example of data coupling is the inheritance of an object. In a software application, one module can use another module’s data and parameters.
Another type of coupling is a rigid sleeve coupling. This type of coupling has a pipe with a bore that is finished to a specified tolerance. The pipe contains two threaded holes for transmitting torque. The sleeve is secured by a gib head key. This type of coupling may be used in applications where a couple of shafts are close together.
Other types of coupling include common and external. Common coupling occurs when two modules share global data and communication protocols. This type of coupling can lead to uncontrollable error propagation and unforeseen side effects when changes are made to the system. External coupling, on the other hand, involves two modules sharing an external device interface or communication protocol. Both types of coupling involve a shared code structure and depend on the external modules or hardware.
Mechanical couplings are essential in power transmission. They connect rotating shafts and can either be rigid or flexible, depending on the accuracy required. These couplings are used in pumps, compressors, motors, and generators to transmit power and torque. In addition to transferring power, couplings can also prevent torque overload.


Different coupling styles are ideal for different applications, and they have different characteristics that influence the coupling’s reliability during operation. These characteristics include stiffness, misalignment capability, ease of installation and maintenance, inherent balance, and speed capability. Selecting the right coupling style for a particular application is essential to minimize performance problems and maximize utility.
It is important to know the requirements for the coupling you choose before you start shopping. A proper selection process takes into account several design criteria, including torque and rpm, acoustic signals, and environmental factors. Once you’ve identified these parameters, you can select the best coupling for the job.
A gear coupling provides a mechanical connection between two rotating shafts. These couplings use gear mesh to transmit torque and power between two shafts. They’re typically used on large industrial machines, but they can also be used in smaller motion control systems. In smaller systems, a zero-backlash coupling design is ideal.
Another type of coupling is the flange coupling. These are easy to manufacture. Their design is similar to a sleeve coupling. But unlike a sleeve coupling, a flange coupling features a keyway on one side and two threaded holes on the other. These couplings are used in medium-duty industrial applications.
Besides being useful for power transmission, couplings can also prevent machine vibration. If vibration occurs in a machine, it can cause it to deviate from its predetermined position, or damage the motor. Couplings, however, help prevent this by absorbing the vibration and shock and preventing damage to expensive parts.
Couplings are heavily used in the industrial machinery and electrical industries. They provide the necessary rotation mechanism required by machinery and other equipment. Coupling suppliers can help customers find the right coupling for a specific application.

Criteria for selecting a coupling

When selecting a coupling for a specific application, there are a number of different factors to consider. These factors vary greatly, as do operating conditions, so selecting the best coupling for your system can be challenging. Some of these factors include horsepower, torque, and speed. You also need to consider the size of the shafts and the geometry of the equipment. Space restrictions and maintenance and installation requirements should also be taken into account. Other considerations can be specific to your system, such as the need for reversing.
First, determine what size coupling you need. The coupling’s size should be able to handle the torque required by the application. In addition, determine the interface connection, such as straight or tapered keyed shafts. Some couplings also feature integral flange connections.
During the specification process, be sure to specify which materials the coupling will be made of. This is important because the material will dictate most of its performance characteristics. Most couplings are made of stainless steel or aluminum, but you can also find ones made of Delrin, titanium, or other engineering-grade materials.
One of the most important factors to consider when selecting a coupling is its torque capability. If the torque rating is not adequate, the coupling can be damaged or break easily. Torque is a major factor in coupling selection, but it is often underestimated. In order to ensure maximum coupling performance, you should also take into consideration the size of the shafts and hubs.
In some cases, a coupling will need lubrication throughout its lifecycle. It may need to be lubricated every six months or even once a year. But there are couplings available that require no lubrication at all. An RBI flexible coupling by CZPT is one such example. Using a coupling of this kind can immediately cut down your total cost of ownership.
China Good quality CZPT Precision Excavator Hydraulic Pump Coupling to Engine Flywheel Eh70   coupling pipeChina Good quality CZPT Precision Excavator Hydraulic Pump Coupling to Engine Flywheel Eh70   coupling pipe
editor by CX 2023-05-26

Chinese wholesaler China in Bournemouth United Kingdom Factory Hydraulic Hose Two Piece Eaton Pipe Fittings Coupling with top quality

Chinese  wholesaler  China  in Bournemouth United Kingdom  Factory Hydraulic Hose Two Piece Eaton Pipe Fittings Coupling with top quality

We – EPG Group the bigge EPT gearbox & motors , vee pulleys, timing pulleys, couplings and gears factory in China with 5 different branches. For more details: Mobile/whatsapp/telegram/Kakao us at: 0086~13083988828 13858117778 0571 88828

√1. Hot Products

One Piece Stainless Steel Hose Fittings

QC Hydraulics designs and manufactures stainless steel one piece style crimp hose fittings, which meet SAE & EPT Specs. One piece crimp fittings are easy to crimp on hydraulic hoses.

QC Hydraulics focus on super quality stainless steel materia EPT only, every batch of fittings with pulse experiments. We guarantee you will receive 100% quality fittings from QC Hydraulics.

QC Hydraulics is carrying 43, EPT & BW series crimp fittings that can be used for 1 ,2 wire hose and spiral hoses. More series crimp fittings are coming soon…

 Stainless Steel Reusable Hose Fittings

QC Hydraulics stainless steel reusable hose fittings are an excellent choice for emergency repairs. Assembly can be accomplished with hand wrenches;
there is no crimper required. Properly assembled, a hose with reusable fittings will meet all applicable SAE specifications.

Stainless reusable hose fittings are vailable for SAE 100 R2 & SAE 100 R5 hoses. Of course, we can make a custom from customer’s drawings or samples.

Two Piece Stainless Steel Hose Fittings & Ferrules

QC Hydraulics two piece style hose fittings and ferrules are compatible with Eaton designs, which meet SAE, JS, BSP, DIN & ISO Specs. The ferrule used with two-piece fittings allows greater flexibility in hose selection and connection, including 1SN, 2SN and multi-spiral hoses which allow for multiple two-piece fitting and ferrule options to accommodate the specific application.

√2. Technical Support

QC Hydraulics engineering has the capacity to design drawings conform to SAE, BS, JIS, DIN & ISO specifications. 

√3. Production Process

√4. Shipping 

√5. Certificate 

QC Hydraulics has been granted ISO 9001:2015 & S EPT certificates for processing stainless steel hydrualic hose fittings and adapters.

√6. Trade Fairs

QC  Hydraulics attends trade fairs 2-3 times every year.  For examples, Hannover Messe 2019…

√7. QC Hydraulics Team

√8. Company Introduction

1. Company Profile
HangZhou QC Hydraulics Co., Ltd was founded in 1999, and is an ISO 9001:2015 certified manufacturer of stainless steel hydraulic hose fittings & adapters.

Over the years, QC Hydraulics has grown into a leading manufacturer of stainless steel hydraulic fittings in the world. Over 95% hydraulic fittings exported to EPT countries & regions in the world.

QC Hydraulics is an approved supplier to several of the large EPT manufacturers of hydraulic fittings in the North America and Europe, and helping many of wholesalers & distributors grow lots of business of stainless steel hydraulic fittings in the world.

2. Company Strengths

QC Hydraulics as one of few manufacturers processing stainless steel hydraulic fittings only, all of our stainless fittings are manufactured to the highe EPT standards, meeting or exceeding SAE,DIN,ISO,BS,JIS and international specifications.

We control our own manufacturing, so if you’re in need of a custom solution the engineering team can help with anything from creating a drawing to developing a prototype. This also means controlled quality, as an ISO 9001:2015 certified company, QC Hydraulics adheres to the mo EPT stringent quality control practices, assuring exceptional products.

3. Plant Size

QC Hydraulics covers an area of 5,000 m² with two manufacuturing shops.50+ high precision CNC lathe machines that designed for processing stainless steel material only.

In addition, there are more 50+ necessary relevant corollary equipment. Such as, cutting machines, drilling machines,crimp machines, bending machines, inspection machines, pressure te EPT machines and etc…

4.Quality Assurance & Service

At QC Hydraulics, the design and durability of each fitting assure long-lasting service, even in strongly corrosive and abusive environments. To prove our superior quality, we back up every fitting with product traceability.When you find any poor quality fittings from QC Hydraulics, we guarantee we will 100% make a new replacement for free if you are able to provide the evidence of poor quality fittings.(Traceability code, photos, videos or original samples)

QC Hydraulics has exactly what your customers are looking for. Make QC Hydraulics the single source for all of your stainless steel hydraulic fittings and adapters.

Whether you have an emergency or an ongoing need, give us an email or a call. We deliver the fittings you want, along with the quality, service and competitive price you deserve.

√9. Why Choose Us?

√1. History:
QC Hydraulics is an ISO 9001:2015 certified manufacturer with over 20 year’s manufacturing experience, specializing in hydraulic hose fittings and adapters. We only focus stainless steel material, no carbon steel or brass.

√2. Quality Control Of Raw Material:
1. We only choose the highe EPT quality stainless steel raw material. And metal suppliers provide material te EPT certificates for each shipment.
2. We 100% measure the sizes of bar stock and forging blanks by callipers for each shipment.
3. We use the Portable XRF Analyser to te EPT the key chemical elements of bar stock and forging blanks with 10% for each shipment(Key chemical elements include Cr, Ni, Mo, these chemical elements are very important for the corrosion performance) 
4. Besides, we randomly pick up several of cutting pieces to do further chemical analysis by spectrograph every 10 days to make sure the raw material 100% qualified.

√3. Quality Control Of Production Process:
1. We are using Sigma High-Precision CNC Lathe Machines to manufacture stainless steel hose fittings and adapters.
The features of CNC Lathe Machines:
1). Dual-axis, EPT system
2). Thread cutting tools: EPT Japan, vargus & carmex Israel(Have a very stable performance during machining)

2. We use  callipers to measure the basic sizes. And we use  the thread gages to inspect the threads.

3. We use Contracer & Contour Measuring Machines to inspect the very small angles and diameters.

√4. Inspection:
1. Fir EPT Article Inspection During Process
1).The operator make the fir EPT article according to manufacturing drawings. 
2). The operator will inspect the fir EPT article and record. If the sizes and threads meet the manufacturing drawings, and then the fir EPT article will be put in a special box( the box is for fir EPT article only).
3). Workshop foreman will take second inspection for the fir EPT article.
4). Only passing the inspection by workshop foreman, and then start with mass production.

2. Mass Production After Fir EPT Article Inspection
1).After the fir EPT article approved by operator and workshop foreman, and then start with mass production.
2). During mass production, the operator needs to inspect the threads every 10 pieces, and measure the sizes every 15 pieces. Once any fittings of threads and dimensions out of the specs, all this batch of fittings will be inspected comple tel: +86~13 0571 88828y.
3). The qualified fittings will be fitly put in a plastic box piece by piece.
4). Finally, the finished fittings will be transported to inspection department for final inspection.

3. Final Inspection

1). Appearance: 100% inspection under strong light. No scratch, No burr.
2). Key sizes and angles: 15-20% randomly inspection by callipers and contracer. Once any sizes and angles of fittings out of specs or doesn’t respect to drawings, this batch of fittings will be forced to return back to production workshop to improve or make a new replacement.

3).Threads: 15-20% randomly inspection by right gages. Once any threads out of specs or doesn’t respect to drawings, this batch of fittings will be forced to return back to production workshop to improve or make a new replacement.

√5. After Service:
When clients have any complaints about our products,  we will take a quick action.
We can 100% make a new replacement for free when the client has a complaint about our products.


√10. FAQ

Q: Are you trading company or manufacturer?
A: We are a 100% manufacturer, main products cover stainless steel hydraulic hose fittings and stainless steel hydraulic adapters.

Q: Do you have stock?
A: Currently we made to order, but we do have some stocks for common type raw materials. So we can make a quick action for some urgent orders.

Q: Do you have a MOQ request?
A: Normally our MOQ is 200 pieces. But for some bigger sizes, 50 or 100 pieces is also acceptable for the fir EPT order.

Q: How about your payment method?
A: 30% deposit in advance, the balance payment again EPT the copy of Bill of lading. Of course, I think everything is negotiable.

Q: What about your delivery time?
A: About 30-40 days for common orders. But it depends on the order volume. Of course, if you have an urgent order, we will try be EPT to meet you.

We – EPG Group the bigge EPT gearbox & motors , vee pulleys, timing pulleys, couplings and gears factory in China with 5 different branches. For more details: Mobile/whatsapp/telegram/Kakao us at: 0086~13083988828 13858117778 0571 88828

The use of original equipment manufacturer’s (OEM) part numbers or trademarks , e.g. CASE® and John Deere® are for reference purposes only and for indicating product use and compatibility. Our company and the listed replacement parts contained herein are not sponsored, approved, or manufactured by the OEM.

Chinese  wholesaler  China  in Bournemouth United Kingdom  Factory Hydraulic Hose Two Piece Eaton Pipe Fittings Coupling with top quality

Chinese  wholesaler  China  in Bournemouth United Kingdom  Factory Hydraulic Hose Two Piece Eaton Pipe Fittings Coupling with top quality