Features and Process Application of Sand Casting

Features and Process Application of Sand Casting

Sand casting uses clay-bonded sand as a modeling material to produce castings. It is a process with a long history and  most widely used.

Yide Casting automatic sand casting from China

Yide Casting automatic sand casting

Sand casting has a long history, dating back thousands of years. In terms of its scope of application, sand casting is everywhere in the world.

It is worth noting that, with the vigorous development of various chemically bonded sands today, green sand is still the most important modeling material. Its wide application range and high consumption are beyond comparison with any other modeling materials. According to reports, more than 80% iron castings in the US use green sand, and more than 73% in Japan.

The extremely strong ability to adapt to modeling conditions is also a major feature of green sand. In 1890, the jolt squeeze moulding machine came out. Green sand, which has been used for manual moulding for a long time, was extremely successful in machine moulding. This furthermore laid the foundation for the mechanization and automation of subsequent moulding operations. The modern high-pressure moulding, jet-pressure moulding, air-punching moulding, static pressure moulding and non-shock vacuum pressure moulding and other new technologies are also based on the use of green sand.

The implementation of various new processes has made green sand more important in casting production. Besides, green sand is also facing many new problems. This urges us to continuously strengthen the research and understanding of the green sand.

Nowadays, with the rapid development of science and technology, the demand for castings in various industrial sectors is increasing. At the same time, the requirements for the quality of castings are getting higher and higher. In modern foundries, the productivity of molding equipment has increased to an unprecedented level. If the performance of the molding sand cannot be fully adapted to the specific production conditions, or the stability and consistency of the molding sand cannot be effectively controlled, it will not take long for the foundry to fail.

With the development of science and technology, foundries that use green sand generally have sand treatment systems suitable for their specific conditions, including old sand treatment, new sand and auxiliary materials, sand mixing, and sand performance monitoring.

There are many constantly changing factors in the green sand system. For example, if one or several key properties cannot be kept within the control range, problems may occur in production. An effective sand processing system should be able to monitor the performance of the sand. At the same time, if there is any problem, the system should be able to correct it in time.

Due to the different arrangements of sand treatment systems and equipment used in various foundries, it is impossible to draw up a set of general control methods. Here, I intend to put forward some control points that have been widely recognized. After carefully understanding these points, each foundry can determine feasible control methods according to its own specific conditions. Moreover, with the advancement of technology and the actual capacity of the factory (including personnel and funds), the control of the molding sand system must be continuously improved.

How to Choose Forklift Parts?

How to Choose Forklift Parts?

1. Check whether the part numbers and specifications of forklift parts are appropriate

Most forklift parts have a specific part number and technical parameters. When purchasing electrical system accessories, pay attention to checking whether the voltage and power are consistent with those of the replaced accessories. When purchasing forklift engine drive belts, pay attention to the model and length width.

2. See if the trademark logo on the outer packaging is complete

The outer packaging quality of high-quality forklift parts is relatively good. At the same time, the writing on the packaging box is clear, and the overprint color is bright. Some important components, such as generators, starters, hydraulic pumps, etc., are also equipped with instruction manuals, certificates and inspectors’ stamps to guide users in the correct use of maintenance methods. Therefore, you should carefully recognize when purchasing to prevent buying fake forklift parts.

3. See if the shape and size of forklift parts are deformed

Some forklift parts are prone to deformation due to improper manufacturing, logistics, and storage.

  • You can roll the shaft part along to see if there is light leakage at the joint between the parts. And roll the glass plate to judge whether it is bent.
  • When choosing the forklift clutch driven disc steel plate or friction plate, you can hold the plate close to your eyes to observe whether it is warped.
  • When choosing seals such as forklift oil seals, the end surface of the oil seal with a frame should be in a perfect circle, which can be fitted to the plate glass without warpage. And the outer edge of the non-skeleton oil seal should be straight. You can hold it by hand to deform it to see if it is able to return to its original shape after letting go.
  • You should also use professional measuring tools to check the geometric dimensions and shapes when purchasing gaskets.

4. Check whether the joint parts of the forklift parts are flat

In the process of handling and storage of forklift parts, burrs, indentations, breakages or cracks may occur at the joints due to vibration and bumps, which may affect the installation and use of forklift parts. Therefore, you should check the joint parts during purchase or inspection.

5. Check for rust on the surface of forklift parts

The surface of qualified parts has both a certain precisionand a bright finish. The more important parts are, the higher the precision, and the stricter the rust and corrosion protection of the packaging. You should replace the parts if they are found to have rust spots, mildew spots, cracked rubber parts, loss of elasticity, or obvious cutting tool lines on the surface.

6. Check whether the protective surface of forklift parts is intact

Most accessories are coated with a protective layer at the factory. For example, piston pins and bearing bushes are generally protected by paraffin, while the surfaces of forklift piston rings and cylinder liners are coated with anti-rust oil and wrapped in wrapping paper. The valves and pistons of forklift engine parts are soaked in anti-rust oil and sealed in plastic bags. You should return or exchange the parts if the sealing sleeve of the sealed bag is broke, the packing paper is missing, or the rust preventive oil or paraffin is lost.

7. See if the glued parts are loose

The forklift parts formed by two or more parts are formed by pressing, bonding or welding. No looseness between the accessories is allowed. For example, the forklift oil pump plunger and the adjusting arm are assembled by pressing; the forklift clutch pressure plate and the clutch plate are riveted; the forklift friction plate and the steel plate are riveted or glued; the filter core frame and filter paper of various filter elements are glued; the circuit wires of electrical equipment are welded. You should replace the parts if find and looseness during purchase.

8. See if the rotating parts are flexible

When purchasing a forklift oil pump and other rotating parts assembly, turn the pump shaft by hand to feel flexible and free from jamming. When purchasing a needle roller bearing, support the inner ring of the bearing with one hand and rotate the outer ring with the other hand. The outer ring should be able to rotate quickly and freely, and then gradually stop. If the rotating parts do not rotate properly, it means that the internal rust or shape has been deformed, which will affect the use, and should be returned or replaced.

9. See if there are any missing parts in each assembly

For high-quality forklift assembly components such as the clutch or transmission of the forklift transmission system, the parts and accessories must be complete and intact to ensure the smooth and normal operation of the assembly. If individual small parts are missing, the assembly parts will not work or even be scrapped.

10. See if the assembly marks of forklift parts are clear

In order to ensure that the assembly relationship of other mating parts meets the technical requirements, assembly marks are engraved on the surface of some parts (such as timing gears). If there is no mark or the mark is fuzzy and unrecognizable, it will bring great difficulties to the assembly work, or even bring out wrong installation.

11. Check whether the mating surface is worn or not

If there are signs of wear on the mating surface of the accessories, or the painted accessories find old paint after removing the paint on the surface, it is mostly disguised as scrap parts. In this case, you can directly request a replacement.

12. Check whether the surface hardness of forklift parts meets the standard

The surface hardness of each mating part has specified requirements. After confirming the purchase and negotiating with the merchant, the stubble of the hacksaw blade can be used to test scratch. If there is no scratch when scratching, it means that the hardness is high. If there are obvious marks after scratching, it means that the hardness is low. However, it is necessary to pay attention not to damage the working surface of the accessories during the test.

How to Clean Cast Forklift Parts

The usability of cast forklifts is now more extensive. Manual loading and unloading of goods have become a thing of the past. Casting forklifts not only bring good work efficiency to workers, but also reduce labor costs for enterprises. So the iron cast forklifts play an important role in the modern industry.

In fact, many parts of forklifts need to be maintained, not only the vehicle body, but also the system. Only in this way can the forklift maintain good working performance. When doing maintenance for the forklift, you need to check the different types of accessories to see if they are aging.

The maintenance of forklift cast parts is very important. If an abnormal situation is found in a certain position of the forklift, it should be checked in time to avoid affecting the work quality. When necessary, you need to contact a professional forklift maintenance master to avoid bigger problems.

So, today we will introduce several methods for cleaning forklift parts

Precautions for cleaning forklift parts: The cleaning method should be reasonably selected according to the cause and characteristics of the oil pollution to ensure the normal use of the parts, avoid corrosion or damage to the parts, and prevent environmental pollution and subsequent contamination of the parts.

1. Vibration cleaning

Place the parts to be cleaned on the cleaning basket or cleaning rack of the vibrating washer and immerse them in the cleaning liquid. The vibration generated by the cleaning machine simulates the manual rinsing action and the chemical action of the cleaning liquid to remove oil stains.

2. Ultrasonic cleaning

Rely on the chemical action of the cleaning liquid and the ultrasonic oscillation introduced into the cleaning liquid to remove oil stains.

3. Spray washing

Spray a cleaning fluid with a certain pressure and temperature on the surface of the parts to remove oil stains. This method has good cleaning effect and high production efficiency, but the equipment is complicated, and it is suitable for cleaning parts with less complicated shapes and serious grease stains on the surface.

4. Scrub

Put the parts in a container filled with diesel, kerosene or other cleaning fluid, scrub with cotton yarn or scrub with a brush. This method is easy to operate, simple in equipment, but low in efficiency, and is suitable for a single small batch of small parts. In general, gasoline is not suitable for use because of its fat-soluble properties, which will harm people’s health and easily cause fires.

5. Boil and wash

Put the prepared solution and the parts to be cleaned into a cleaning pool of appropriate size welded with steel plates, heat it to 80~90℃ with an under-pool stove, and cook for 3~5min.

Yide casting is a leading casting foundry in China, with 27 years’ experience, produces top quality forklift iron cast fitting, if you are interested in our casting fitting, please send us a drawing file, and feel free to get a quite quote.

Influencing Factors of Foundry Sand Casting Cost

There are many factors that affect the cost of sand casting. Here, we have listed some of the main factors, and hope that this information can help our casting customers.

1. Cost of pig iron and scrap steel

Pig iron and scrap steel is the main material of cast iron and cast steel, so their price will directly affect the cost of sand casting.

2. Alloy cost

If your casting parts need to add alloys such as chromium, nickel, copper and molybdenum, then their prices will be more expensive than ordinary metal grades.

3. Casting process

Different casting processes will greatly affect the cost of castings. The cheapest is the molding sand casting process, then resin sand casting is more expensive, and the pre-coated resin sand casting process (eg hot shell and core molding process) will be the most expensive process.

4. Resin cost

As for the casting process with resin sand and pre-coated resin sand, the price of resin will affect the cost of the casting, but it will not affect the sand casting process.

5. The size and weight of the casting

As for small castings weighing less than 1 kg, the price per kg will be much more expensive than large castings because they will lead to more production time and grinding works.

6. Sand core

If your casting parts need to use sand cores in the production, then its cost will be higher than that without sand cores. This is because the sand cores need to be produced separately.

7. other factors

In addition, there are many other factors. The annual demand is greater, then their prices will decrease. Simpler sand castings will be cheaper. Material grades will affect difficult production and heat treatment, so materials with higher grades are more expensive. Higher requirements summing up surface quality and casting defects will lead to higher production costs because of the scrap rate. In addition, there are other factors such as processing costs, painting and packaging costs.

Therefore, they are many factors that affect the cost of sand casting. Therefore, it is inaccurate to estimate its cost only through a calculation formula. This foundry needs to consider these factors based on production experience and current prices of materials and labor.

Causes and solutions of casting deformation

Causes and solutions of casting deformation

Deformation means the mismatch between the whole or part of the casting and the design. Then what are the causes of deformation, and what are the solutions to deformation? Today, Yide Casting will introduce the causes and solutions for you.

Causes of deformation:

1. Uneven shrinkage caused by the unreasonable design of casting;

2. The mold temperature is too high, with insufficient hardness, and the cooling time is not enough.

3. The mold shell design is not reasonable;

4. There is mucosa on the casting;

5. The temperature difference between different parts of the cavity is relatively large, and the cooling operation is uneven.


Solutions to deformation:

1. Improving the structure of casting, in order to increase the inner wall thickness of the mold shell appropriately;

2. Increasing the cooling time so as to low down the temperature of the mold shell;

3. Adjusting different parts of the mold shell appropriately, especially balance the top part;

4. Cleaning away the mucosa on the casting;

5. Controlling the casting temperature, so as to ensure that the overall temperature in the cavity is balanced.

How a Forklift Oil Pump Works in the Hydraulic System?

  • Working principle of forklift hydraulic system

The basics of the hydraulic system go like this: Confined oil has pressure on it from one side. That pressure forces the oil against a piston on the other side of the container. That transfers energy into the piston, forcing it upward. The piston cannot move in the opposite direction unless the pressure is released. In terms of the forklift hydraulic system, the pistons raise the forks and keep them lifted until the hydraulic pressure is released by the operator.

  • Composition and function of forklift oil pump

Forklift piston oil pump is mainly composed of small forklift parts such as pump body, seal, oil outlet and inlet valve etc. Its function is to suck the oil used by the forklift from the oil tank to generate a certain pressure of the oil to overcome the resistance of the oil filter and pipeline, and to ensure continuous delivery of sufficient oil to the oil injection pump.

Working principle diagram of forklift oil pump



  • The forklift oil pump is installed in the forklift hydraulic system. Now, let me introduce the safety technical requirements of forklift hydraulic system accessories.

Forklift hydraulic system accessories occupies an important position in the use of forklifts. Forklift working device accessories mainly rely on hydraulic system for lifting, tilting and other actions. The working condition of the forklift hydraulic system will directly affect the working condition of the forklift. Once the hydraulic transmission system parts of the forklift have malfunctions, it will inevitably bring direct unsafe consequences. Therefore, it is important for the safe operation and driving of the forklift to maintain the hydraulic system in strict accordance with the safety technical requirements. The following are the safety technical requirements for forklift hydraulic system:

  1. The oil level of the oil tank shall not be lower than the oil mark line of the oil level indicator. And the application of hydraulic oil shall comply with the regulations. At the same time, the oil shall be clean, and the filters shall not be blocked.

  2. The overflow valve should be sensitive and reliable; The nuts of the adjusting bolts must be complete; And the pressure regulation should meet the equipment requirements.

  3. The components, pipelines and joints of the forklift hydraulic system should be unblocked. There is no leakage of the seal, no friction with other accessories, and no aging or deterioration of the rubber hose. The internal leakage should be within the allowable range.

  4. The compression spring of the forklift multi-way valve must be intact, and the valve stem can be quickly back to position when eliminating the external force. The joystick should have a certain strength and rigidity, the surface should be smooth, without deformation. And the joystick should be positioned reliably, and not displaced due to vibration. The overflow valve should be sensitive and fully open when overloaded by 25%. And the nuts of the adjusting bolts should be fully tightened.

  5. Crawling, stagnation and significant impact should not occur within the rated speed range of each hydraulic cylinder.

  6. Each high-pressure hose should undergo a pressure test and meet the specified requirements.

  7. Various control valves should be safe, reliable, and sensitive.

The Maintenance and Common Faults of Manual Hydraulic Pallet Jack

Today, we will introduce the maintenance and common faults of manual hydraulic pallet jack to you as follows.

Daily Maintenance:

1. Adding oil

Check the oil level once a month. We recommend you to use 32# hydraulic oil.

2. Exhaust

Due to transportation or the inversion of the pump body, air is likely to enter the hydraulic pump. This will cause the failure to lift cargo when the pressure is suppressed in the rising position. You can operate exhaust according to the following steps: pull the top of the handle to the down position, then lift up. Thus repeat for several times.

3. Daily inspection and maintenance

Routine maintenance is indispensable, and the focus should be on the maintenance of wheels, core axis and rags. When finish handling, we should remove the items on the fork and lower the fork frame to the lowest position.

4. Lubricant

We should add all bearings and shafts with lubricating oil. We only need to add lubricating oil to all moving parts at monthly intervals or during each thorough inspection.

iron casting oil pump

Common faults:

Fault 1: The fork cannot rise to the highest position

Cause analysis: insufficient hydraulic oil

Repair method: add hydraulic oil


Fault 2: The fork does not rise

Cause analysis: there are impurities in the hydraulic oil, the pressure relief valve is not adjusted properly, or there is air in the hydraulic oil.

Repair method: replace clean hydraulic oil, adjust set screw, remove air.


Fault 3: The fork does not drop

Cause analysis: the piston rod of the cylinder is deformed due to unbalanced load, parts are damaged or deformed due to unbalanced load, and the pressure relief valve is not adjusted properly

Maintenance method: replace the piston rod or cylinder, repair or replace related parts, adjust the set screw,


Fault 4: Leakage

Cause analysis: worn or damaged seals, cracked or worn parts

Repair method: replace new seals, check and replace new parts


Fault 5: The fork drops when the pressure is not released

Cause analysis: maybe there is impurities in the hydraulic oil, air in the hydraulic oil, the seal is worn or damaged, or the pressure relief valve is not adjusted properly.

Maintenance method: replace clean hydraulic oil, remove air, replace new seals, adjust set screws