1. Introduction

 

In modern homes and commercial spaces, dual flush toilets have become a mainstream choice for water conservation and environmental protection. Unlike traditional single-flush toilets, dual flush toilets offer two flushing modes—half flush and full flush—allowing users to select the appropriate water volume based on actual needs, effectively reducing water waste.

The design of dual flush toilets not only aligns with sustainability trends but also helps lower long-term water costs while providing more efficient flushing performance. Whether in homes, hotels, or public restrooms, dual flush toilets are widely favored for their water-saving, efficient, and durable features.

In this article, we will explore the water fittings of dual flush toilets and provide a detailed introduction to their key components, helping you better understand and choose the right products.

 

2. Water Fittings of a Dual Flush Toilet

 

The efficient operation of a dual flush toilet depends on the coordination of several core water fittings, each playing a crucial role in controlling water flow, optimizing flushing performance, and conserving water.

In general, the primary water fittings in a dual flush toilet include the toilet fill valve, toilet flush valve, and toilet flush button. Among these, the toilet flush valve and toilet flush button are key to the dual flush system, determining how the half and full flush functions are executed.

• Toilet Flush Valve: This component is responsible for releasing water from the tank to flush the bowl. Dual flush toilets typically use either a bucket-type dual flush valve or a cable-operated dual flush valve, ensuring precise water flow control and effective flushing.
• Toilet Fill Valve: This component controls the refilling of the toilet tank after flushing, maintaining a stable water level to ensure proper operation.
• Toilet Flush Button: The user operates the button to choose between a half or full flush. Depending on the installation type, toilet flush buttons can be top-mounted, side-mounted, or wall-mounted (for concealed cisterns).

A well-configured set of water fittings not only impacts flushing performance but also determines the toilet's lifespan and maintenance costs. In the following sections, we will provide a detailed overview of toilet flush valves and toilet flush buttons, helping you understand their functions and key selection criteria.

 

3. Introduction to Key Components

 

3.1 Toilet Flush Valve

• Function: The toilet flush valve is the core component of the toilet’s flushing system, controlling water release for both half and full flushes.
• Common Types: Bucket-type dual flush valve and cable-operated dual flush valve. These two designs differ in installation and operation but both effectively manage water volume and optimize flushing performance.
• Selection Criteria:
  • Size: Choose between a 2-inch or 3-inch toilet flush valve based on the toilet’s flush outlet size to ensure compatibility.
  • Overflow Pipe Height: Ensure it matches the toilet tank height to prevent overflow issues.
  • Overall Toilet Flush Valve Height: Should fit within the tank space for stable installation and effective flushing performance.

Selecting the right toilet flush valve can enhance the toilet’s flushing performance while reducing water consumption and maintenance costs. When installing or replacing a toilet flush valve, always ensure it matches the toilet’s specifications for the best results.

3.2 Toilet Flush Button

• Function: The toilet flush button is a critical user interface component that operates the toilet flush valve, allowing selection between half and full flush modes.
• Common Types: Based on installation type, toilet flush buttons can be top-mounted, side-mounted, or wall-mounted, suitable for different toilet designs.
• Selection Criteria:
  • Button Size: Common sizes include 38mm, 48mm, and 58mm. The correct size should match the tank hole diameter for proper installation.
  • Installation Type: Determine whether a top-mounted or side-mounted toilet flush button is required, depending on the toilet design.
  • Wall-Mounted Button Compatibility: For concealed cisterns, ensure the flush plate is compatible with the concealed tank, preventing installation and operational issues.

Choosing the right toilet flush button affects user experience and ensures precise flushing control. When selecting a toilet flush button, consider the toilet tank structure and personal preferences to achieve optimal convenience and performance.

 

4. Conclusion

 

Understanding the water fittings and key components of dual flush toilets reveals that selecting the right toilet flush valve and toilet flush button requires considering multiple factors, such as flush outlet size, overflow pipe height, installation type, and button size. These factors determine compatibility and performance, making the selection process complex for different markets.

For buyers uncertain about local toilet specifications or dealing with a variety of toilet types in their market, the most hassle-free solution is to choose a cable-operated dual flush valve with an adjustable overflow pipe. This type of toilet flush valve allows height adjustment to fit different tank designs, reducing installation issues. In this case, buyers only need to focus on the toilet flush valve size (2-inch or 3-inch) and toilet flush button size (38mm, 48mm, or 58mm), simplifying the selection process while ensuring a high success rate in compatibility.

Selecting the right water fittings not only enhances toilet performance and durability but also minimizes the risk of installation errors and additional costs. Jielin Plumbing offers a wide range of high-quality dual flush toilet accessories, catering to different market needs and helping buyers easily find the most suitable products.

Both Screw jack and servo electric cylinder can realize the mechanical movement into linear or straight push/pull movements. They are ideal for all types of applications where tilting, lifting, pulling or pushing with pounds of force are required.

In comparison, due to the servo motor and servo electric cylinder screw jack combination makes the servo electric cylinder of thrust, speed and position control is more precise and therefore is widely used in modern digital and network technology, and other fields, which can realize programmed control, so the cost is higher.

SWL screw jack can be optionally equipped with a protective cover. However, during actual selection, most customers did not choose a protective cover. It may be due to cost-saving reasons, or there may be no choice due to other reasons.

Today Lude Transmission will take you to know about the protective cover, which is not only applicable to SWL screw jacks, but also to other types of screw jacks.

We divide the protective cover into two types, which are installed in the upper area A and the lower area B of the screw jack (see the picture below).

The screw rod part that is constantly telescopic and moving uses a soft protective sleeve, also called a bellows boot. The bellow boot can expand and contract with the expansion and contraction of the screw rod, so that it is not easy to cause damage to the protective cover. Just install the protective pipe on the lower part as a protective cover. Divided into cylindrical type and square tube type.

What if it is a nut movement screw jack? The nut movement can also be fitted with a dust cover. Just install a bellows above and below the nut.

The protective cover plays a very important role in protecting against dust, oil, corrosion, etc. If you have enough budget, it is still recommended to choose a protective tube and dust cover.

If you need this product, please feel free to consult us.

Bevel gear jacks use the same trapezoidal or acme screws used in machined screw jacks to move the load. However, bevel gear jacks use bevel gears inside the housing instead of worm gearing. Bevel gears are more efficient than worm gearing，and they have lower ratios that result in higher speeds and travel rates. Typically, bevel gear jacks maintain self-locking characteristics while providing higher travel speeds.

Another benefit of bevel gear jacks is their I/O shaft flexibility. They are available in single shaft, two shaft and three shaft configurations. In two and three shaft configurations the jack offers right angle characteristics with the ability to divide input power or torque, sending it equally in different directions. Flexibility in shaft configuration makes bevel gear jacks ideal for multiple jack configurations and can eliminate the need for stand-alone right angle gearboxes used in many worm gear jack systems.

Bevel gear jacks are well suited for light and moderate duty cycle applications and they are priced slightly above worm gear or machined screw jacks because of their greater efficiency, flexibility and speed characteristics. While a bit more expensive, bevel gear jacks reduce the number of required components in multiple jack systems, which helps balance the difference in price.

There are two types of basic transmission forms of screw jacks.

1.Nut Movement

In Brief: When the worm shaft is rotated the lead screw rotates in the body of the screw jack at the same rate as the worm gear. The nut on the lead screw moves in a linear direction along the screw when fixed to a structure that prevents it from rotating with the screw. This design is also available with a “Safety Nut”.

In Detail: When a screw jack unit is operated, the rotation of the worm shaft causes the worm gear to rotate. For rotating screw jacks the lead screw is fixed to the worm gear and they rotate at the same speed. As the worm gear turns, the friction forces on the screw thread act to turn the nut also. The greater the load on the screw jack unit, the greater the tendency of the nut to turn. It is obvious that if the nut turns with the screw, it will not raise the load. Therefore the nut needs to be fixed to a structure to prevent rotation.

2.Screw Movement

In Brief: The lead screw translates through the body of the screw jack when the lead screw is prevented from rotating with the worm gear. This is typically done by fixing the end of the lead screw to the structure that needs to be moved linearly.

In Detail: When a screw jack unit is operated, the rotation of the worm shaft causes the worm gear to rotate. For translating screw jacks the worm gear is threaded to accommodate the lead screw thread. As the worm gear turns, the friction forces on the screw thread act to turn the screw also. The greater the load on the screw jack unit, the greater the tendency of the screw to turn. It is obvious that if the screw turns with the nut (worm gear), it will not raise the load. In those cases where a single unit is used, and where the load cannot be restrained from turning, it is necessary to screw jack with an anti-rotation mechanism (keyed screw jack).

What should you pay attention to when using the screw jack? This is also crucial for us who often use jacks .It enables us to better understand the screw jacks, thus reducing unnecessary troubles during use.

The specific precautions for the screw jack are as follows:

Firstly, always keep the surface of the screw jack clean, regularly check whether the internal structure is intact, make the pinion in the rocker flexible and reliable, and lift the lifting sleeve freely.

Secondly, the friction surface between the lifting sleeve and the housing must be oiled at any time. Other oil filling holes should be lubricated regularly.

Thirdly, in order to take into account the safety in use, the jack should not be overloaded, work with illness, it is not appropriate to use more than one to avoid danger.

Fourthly, The screw jack must be checked regularly, depending on the level of use and the working environment. It is advisable to check if there is a lubricant leak in the housing. If this happens, you need to find and remove the cause and fill the lubricant with the correct level.The lubrication conditions of the threaded spindle must be checked regularly (if necessary, recovery must be made) and the presence of any foreign matter. Safety components must be inspected according to applicable specifications.

When facing with the need to lift, lower, push or pull a load,especially a heavy load and hold it in the correct position, as crew jack or multiple screw jack system may provide the best linear motion solution when considering its performance/cost ratio. There are 3 main types of screw jacks:machine/worm gear screw jacks,ball screw jacks, and bevel gear screw jacks. Within these, there are 3 subcategories related to the mode of operation: Translating, Keyed, and Rotating/Traveling nut.  Let's see how these three subcategories move in below ,

In order to know if a screw jack or screw jack system could be a solution for your application, you will need to consider which type of screw jack to select. There are worm gear screw jacks, bevel gear screw jacks and ball screw jacks, and each has several different options and configurations.

To determine the type of screw jack that is best for your application, you need to consider several factors, including: load, self-locking capabilities, travel rate or travel speed, efficiency, accuracy, duty cycle and price,etc.

The double-section screw structure consists of two screws and two nuts. The diameter of the first-stage screw is larger than that of the second-stage screw. There is a keyway on the first-stage screw, and the inner hole of the worm gear is a through hole with a keyway. When the worm gear rotates counterclockwise, the key structure drives the first-stage screw to rotate. A nut with an internal thread is installed above the turbine and fixed on the top of the box. It cooperates with the thread of the first-stage screw. The screw and the nut produce relative movement, and the screw rises or falls. The second-stage structure is also a combination of a pair of nuts and screws. The secondary nut is connected to the primary screw and rotates and rises and falls with the primary screw. The secondary screw is connected to the user’s equipment. The screw does not rotate, but only rises and falls.

1. The primary and secondary screws have the same axis;
   
2. Compact structure, small size, saving space and cost;
   
3. Reduce the weight of the overall platform, reduce the output power of the drive source, energy saving and environmental protection;
   
4. Double the speed. Compared with a single-section screw, the speed is twice that of a single-section screw at the same input speed;
   
   
   

The screw jack system is widely used in situations with long spans and excessive loads. The use of screw jacks typically involves a multi-unit synchronized configuration. This approach ensures that the load on each individual screw jack does not exceed its capacity, guaranteed sychronized movement of all units to prevent lateral forces, and ehances overall stability and safety of the solution.

The desigan phase for a synchronized screw jack system is crucial,requiring customers to provide relvent data and considering installation space, operating conditions, limit switches, and other aspects. However, after completion and production delivery, on-sit installation at the customer's premises is equally important. We need to pay attention to various issues such as center height alignment,coaxiality, guide devices,and gearbox orientation determination.

Today we want to discuss how to avoid excessive deviations during the multi-unit screw jack system.First, let's start with the perparation steps: After receiving the screw jacks from the customer, it's necessary to ensure that the output and input shafts of units like gearbox and motors are at the same horizontal level. If there is a difference in center height, you can chosse to add appropriate thickness washers to make them consistent. When connecting with couplings or connection rods, it's necessary to calibrate coaxiality to prevent tilting or binding situations.

If a lifting platform is required, attention must be paid to its installation. We need to ensure that the mountibng surface of the screw or nut is at the same horizontal heigth, and the mounting surface of the screw jack should also remain level.Additionally, adjust the mounting holes of the screw head(or nut mounting holes)so that they align with the mounting holes of the support platform before installation installing it. It's important to note that during installation,lateral forces should not be applied to the screw. Lastly, to avoid excessive deviation when multiple screw jack system are installed, we must confirm that there are no errors in the dimensional deviations of each axis before connecting the equipment.Before assembling the screw jack with the driven source and other devices., check for dimensional deviations in shaft diameters,keys, and keyways to prevent damage to bearings from over-tightening or affect power transmission from under-tightening.After installation, lubricate all necessary parts and conduct test runs.If any issues arise during testing, immediately stop operation and only restart once everything is confirmed to be normal.

Screw stability verification: known load 100KN, stroke 500mm, speed 60mm/min, no guide rail, usage coefficient 1.5, low operating frequency, calculated model For (Heavy Duty Electric Linear Actuator model SCA200-V1-500-FL-P2):

lifting Screw specification Tr80*12

1. Known conditions

Load F=100KN=100,000N

Stroke S=500mm

Speed v=60mm/min

Usage coefficient K=1.5

Screw specification Tr80*12 (diameter 80mm, pitch 12mm)

2. Analysis of screw force

The screw mainly bears the axial load, so we need to calculate the stress of the screw under the axial load.

• Screw diameter d=80mm=0.08m

•Screw cross-sectional area A=π (2d)2= π(20.08)2=0.005027㎡

•Axial load Fax=K*F=1.5×100,00N=150,000N

3. Calculation of screw stress

Screw stress o =AFax=0.00502715000=2983866.67Pa

4. Check the stability of the screw

For the stability of the screw, we mainly pay attention to whether it will flex. Since the screw is usually installed on the fixed bracket and its length is relatively short (500mm), the possibility of buckling is relatively small. However, in order to evaluate more accurately, we can use Euler's formula to estimate the critical bending load of the screw.

1. Screw length=500mm=0.5m

2. The elastic modulus of the screw material E (set to steel, E≈210GPa=210×109Pa)

3. Screw moment of inertia I=π 64d4= π64×(0.08)4=2.01062×10-7m4

Eular critical load Fcr can be calculated by the following formula:

Fcr=12 π2EI=(0.5)2π 2×210×109×2.01062×10-7=2,649,444.44N

Because Fax=150,000N＜Fcr=2,649, 444.44N, the screw is stable under axial load.

5. Summary
After calculation, it is confirmed that the screw (specification is Tr80*12) equipped with the linear actuator model SCA200-V1-500-FL-P2 is at a load of 100KN, stroke of 500mm, speed of 60mm/min, and a coefficient of use of 1.5 And the linear actuator is stable under the condition of low working frequency.