Analysis on Stone Block Cutter Failure and Ways to Recover It

Stone block cutter is an equipment that has been widely used in stone processing industry. Most stone processing plants have ever experienced some problems with their stone block cutters. For example, unstable performance, machine body shakes when it go up and down, segments consumption too fast, slab surface cut by the machine is not flat, working efficiency is too low, etc. So we can see it that a reasonable and effective maintenance to the machine is helpful for improving production efficiency and product quality.

When the machine turns out to be unstable performance, vibrating or fail to up and down, we can make an analysis from the following 3 aspects.

1) Problems may occur to the stone saw machine.
Fixing bolts get loose in the machine body, speed reducer is out of lubricating oil, gears worn out and bearings break out, spindle radial run out due to too big or too small space between bearings, flange for fixing blade on the spindle is deformed, no enough lubricating oil in the guide rails for machine movement or the lubricating oil is too thin or too thick, rolling wheels press too hard on the rails, cycloidal pin gear speed reducer is broken.

2) Problem may occur to the blade
Too big radial run out in new saw blade, blade central hole and the spindle is not concentric circles, diamond segment is not sharp enough or not suitable for the stone it is cutting, the blade has been welded segments for recycle usage too many times.

3) Problem may occur to the operation
The block trolley is not firmly locked, blade horizontal forwarding speed is too fast, blade vertical feeding depth is too much.

Ways to solve the problems mentioned above.

Pay more attention to the granite saw machine spindle box. Check to find out if the spindle radial run out is beyond acceptable range. If the spindle radial run out is out of acceptable range, adjust bearing pressing bolts to recover it.

Check to find out if the bearings, gears, blade spindle and bearing spindles are in good condition. Evaluating their wearing extent to make decision whether to replace or repair them.

Check to find out why the speed reducer box is out of lubricating oil. If it is caused by the failure of sealing ring, replace it by a new one.

Check to find out if the fixing bolts on the machine body are tight or loose. If getting loose, tight them again.

Check to find out if the machine has enough lubricating oil in the guide rails, if not, add more oil for it.

Better Use of Diamond Circular Saw Blade in Block Cutter Machine

We all know that diamond circular saw blade plays a very important role in stone cutting works. Choosing the right diamond circular saw blade can improve block cutter machine capacity by 5% and reduce production cost. Most people like thin circular saw blade. So they can use thin segments as well. Even though that the thin circular saw blade costs a bit higher, they can reduce more cost in segment and electric power, and get more slabs from a stone block. There are 5 tricks for better use of the diamond circular saw blade in block cutter machine.

1. Sharpness Comes First.
The hardness of diamond grits on the circular saw blade should have higher standard than that of normal diamond grits.
The percentage of 40/50# coarse diamond grits account for 60% at least.
The concentration of diamond grits no more than 25% in the segment.
Segment made by low temperature metal binder formula which enables the segment to be sharp and diamond grits not easy to drop off.
Shorten the segment length to 21mm.

2. Smaller Motor Power
The saw blade gets thinner, its rigidity gets lower accordingly, so the saw blade’s friction force during cutting process also gets smaller.
The segment gets thinner and shorter, it faces smaller drag force in cutting process.
The diamond circular saw blade is sharper with higher cutting capacity.
So, if the original motor power is 30kw, now it can be changed to 22kw. The electricity currency controlled to be 35A. Production capacity will keep in the same level.

3. Control the Heat Impact
In welding diamond segments onto the circular saw blade, it is better to use the low temperature silver sheet. The low temperature silver sheet requires short time heating and has small heating impact to the neighboring segments. It’s recommended to keep a distance between the former and latter welding, for example, a distance of 6-8 teeth. When the first round is finish, resume the next round.

4. Operation Techniques
In the beginning of stone cutting, the blade should forward slowly, vertical blade feeding should shallow. When the blade has cut a 30mm deep slot in the stone, then the blade forwarding speed can be higher and blade vertical feeding can be deeper.
Use small circular saw blade first, then comes the bigger saw blade. If you are cutting 600mm width slab from stone block, you can use the dia.1600mm blade to cut directly. If you are cutting 800mm width slab from stone block, you can use the dia.1600mm blade to cut 600mm deep first, then change to dia.2000mm blade to cut the rest 200mm deep.
Execute reasonable blade forwarding speed and vertical feed depth according to the degree of stone hardness. If the stone is very hard, the blade vertical feeding should be shallow and horizontal blade forwarding speed should be fast.
Always rotate the diamond circular saw blade in the same direction for stone cutting. Otherwise the saw blade may be easy to get “tired” and break.

5. Protection Measurement
The thin circular saw blade turns to severe deformation once be sucked by stone. Though that the saw blade can be leveled again after deformation, its quality and service life will be greatly impacted. So it is necessary to take some protection measurements on the multi blade block cutter machine once the blade is sucked by stone.

Why the Multi Blade Granite Cutting Machine Is So Popular in Stone Processing Industry



Gang saw cutting process is not continuous, so its cutting speed is relatively too low. Its low cutting speed has heavily restricted the improvement of stone cutting efficiency. So, a new kind of stone cutting machine is created to solve the problem. That’s diamond circular saw stone cutting machine. This machine is composed of machine body, blade driving motor, diamond circular saw, blade rise/fall guide system and blade horizontal moving guide system, etc. It cuts stone by the diamond circular saw running at high speed and reciprocation movement along horizontal guide rails on the cross-beam. Meanwhile, diamond circular saw falls along vertical guide rail to feed to stone block.

Diamond circular saw stone cutting machine has higher cutting speed than gang saw machine and greatly improves stone processing efficiency. So, diamond circular saw stone cutting machine is the most widely used stone processing equipment nowadays. But it comes with a disadvantage. The circular saw stone cutting machine maximum cutting depth is determined by the circular saw diameter. Usually it can’t exceed circular saw diameter.

It’s said that the biggest circular saw stone cutting machine was manufactured in Germany in 1980. The circular saw diameter was 5 meters. But the blade driving spindle is not strong enough to bear a so heavy saw blade to make vertical stone cutting. Secondly, due to that the circular saw diameter is really too big, the slab surface cut by it is not smooth. So, it is difficult to make the circular saw into a very big diameter, in view of technical aspect. Even though that circular saw stone cutting machine has much higher linear speed than gang saw machine, it can’t cut as deep as gang saw and can’t produce so many pieces stone slab as gang saw at a time. Therefore, circular saw stone cutting machine can’t replace gang saw machine in cutting big size slab.

To furtherly improve stone processing efficiency, multi blade granite cutting machine is created based on single blade circular saw stone cutting machine. In this kind machine, many pieces circular saw are installed on a long spindle with spacer in between to cut stone. Though there is not much change is machine structure, the multi blade granite cutting machine can be mounted as many as one hundred pieces circular saw. So it is able to cut 100 pieces stone slab at a time with very high cutting efficiency.

To get higher level of automation in the multi blade block cutting machine, people add a horizontal blade to the machine. After the vertical blades cut stone block into slabs, the horizontal blade cuts slab off from the stone block. It not only reduces human labor work, but also reduces production cost.

Gang Saw is An Excellent Block Cutting Machine

Gang saw is one of the many widely used stone block cutting machines. It’s composed of saw frame, link rods, vertical pillars and straight band saws. The straight band saws are installed in the saw frame. The link rods motivate the saw frame and straight band saws into reciprocation movement so as to cut stone. Meanwhile, the saw frame vertical transmission mechanism works to feeding the band saws downward on stone block continuously. In the early days, gang saw cuts stone block by steel bands and steel grits. Today the gang saw is highly developed with high level automation and big cutting capacity.

In 1970, Italy was the first country to launch large gang saw machine cutting stone by straight band saws welded with diamond segment. It was able to cut maximum size marble block 3.5-meter long and 2-meter wide. That means that the gang saw can cut 100pcs slab of 2cm thick at a time, about 20% higher capacity than the old style gang saw machine. Currently, the gang saw block saw machine cutting by straight band saws welded with diamond segment is merely used in marble production. It is not qualified to cut harder stones like granite. Because the welded diamond segment is easy to break off from the straight band saw in cutting granite. That’s why granite block is usually cut by steel band saws and steel grits.

Most of the gang saw machines that used in Chinese stone plants are imported from Italy. Even though that some China stone machine manufacturing companies try to learn from Italian technology and produce their own gang saw machine since 2000, most of them still not master the core technology. Their gang saw is not as well as the Italian gang saw in cutting efficiency, cutting cost control and mean time between failures. For China gang saws, problems mainly occurred in the saw frame guide system and band saw hydraulic tensioning system. Italian gang saw are two link rods design while most of China gang saw is single link rod design.

China Stone Cutting Machine Industry and Its Future Development

The stone processing equipment usually includes stone cutting machine, grinding and polishing machine, profiling machine, etc. Stone processing equipment is always developing as the stone industry goes ahead. In China, the stone processing industry is still a young industry compared with other industries that with long history. So, there are still many shortcomings in Chinese stone processing equipment as well as its application. Meanwhile, there is some technology gap between China stone processing equipment and that of international advanced countries. It’s necessary for us to have a clear awareness and summarize it for a better development in the future.

It’s commonly believed that the natural stone is a material coming with many good qualities. For example, it has beautiful texture, elegant appearance, not burn in fire, and resistant to scratch. Even since the ancient times, natural stone has been used for building construction by humans. However, the natural stone processing was completely done by manual work in ancient times, until the first stone cutting machine was created in Europe in the 19^th century. It brought in a revolution for stone processing industry, and from then on, people change from manual work to electric equipment production.

China stone processing industry has experienced a rapid growth since the reform and opening policy about 30 years ago. China stone processing equipment also got a fast development during the last 30 years. There are two periods in history that China import advanced stone processing equipment in large scale from foreign countries, one is the late 80s, the other is the late 90s to the beginning of this new century. By learning from the advanced technology, China stone machine manufacturing technology achieved a great improvement. Today, the Chinese stone cutting machine manufacturers pay more attention to research and offer more and more good machines for stone industry home and abroad.

Who We Are?

Xiamen Chiyi Stone Machine Co., Ltd. is committed to manufacturing a variety of machines and systems for natural stone processing industry. The product range covers bridge saws, granite block cutters, granite cutting machines, granite polishing machines, etc. These machines have been widely used in stone processing plants for sawing stone block, slab & tile polishing, edge cutting, profiling, calibrating, chamfering, etc.

To produce good machine for customer, we only employ specialized staffs who are skillful with field knowledge and experience. They add value to the every single detail in machine part construction and machine assembly. By creating a complete line of precise stone machines with reliable quality and performance, now we not only supply equipment for stone processing plants in China, but also export to Vietnam, India, Ukraine, Russia, Kazakhstan, USA, Australia, and African countries.

We are available by the following contact:
Address: No362 Xiahe Road, Xiamen City, Fujian Province, China
Tel: +86 592 2037326
Fax: +86 592 2037753
Hotline: +86 18906034430
E-mail: sale@bridgesawchina.com
Website: www.bridgesawchina.com