CONSTRUCTION MACHINES

In today’s world, construction machines are indispensable for structural activities. There are machinery serving for different purposes in many sectors such as mining, construction, iron and steel, forestry and agriculture. Equipment such as excavators, dozers, graders, wheel loaders and drills are used in the mining sector.

Our own production is mainly for mining equipment. In order to address our global customers, we closely follow the standards of original equipment manufacturers. We never compromise on original part numbers or original designs. As a result of mutual negotiations with the customer, together, we produce the most suitable solution for them.

We manufacture hydraulic cylinders for light construction machines used in construction, forestry and agriculture. In this sector, construction machines which are 10-45 tons are generally prefered. We provide service to our customers in the vicinity of our production facility. We also produce solutions for our overseas customers according to the part numbers specified by the original equipment manufacturers or according to the machine brand model.

We carry out design works with the customer for the iron and steel industry and produce special hydraulic cylinders in accordance with their requests.

HYDRAULIC CYLINDER

One of the first elements that comes to mind in situations requiring high force is hydraulic cylinders. Hydraulic cylinder is the element that converts the hydraulic fluid coming from the pump into mechanical movement in the circuit it is located.

Hydraulic cylinders, which are also used in construction machines, are used for functions like breakout, digging, drilling, lifting. The design of these hydraulic cylinders varies depending on where they are used. There are many production rules to be taken into consideration such as right material selection, coating on rod surface, welding groove designs, welding operation preparations, tolerancing of parts that need machining, guidening and sealing elements. We are making the right production with our experienced engineers.

The use of hydraulic cylinders is also common in the industrial sector. Iron and steel industry, automotive, hydraulic presses, injection machines, marine and tunneling applications are addressed to many sectors. The design of hydraulic cylinders in these sectors is also an issue that requires attention and experience. For instance, the choice of heat-resistant guidening and sealing elements for the coating industry or the iron and steel industry, which are specific to the maritime industry, are important details.

SELECTION OF SEALING AND GUIDENING ELEMENTS

The parts which are used in the hydraulic cylinder and which have the lowest financial burden are guidening and sealing elements. However, the hydraulic cylinder produces all its power based on these elements. The selection and correct combinations of these elements are crucial to ensure a long-lasting operation that meets the constant pressure or shock pressures that occur inside.

The guidening and sealing elements used in the hydraulic cylinder can be classified into two main groups. These can be grouped as those that prevent internal leaks and those that prevent external leaks.

First of all, if we examine the sealing elements that prevent internal leaks. They are mounted on the part of the hydraulic cylinder called piston and are selected according to the desired environmental conditions ( ex. pressure, speed, temperature, fluid type, etc.). The main seal prevents the decompression, but the guidening elements carry the loads that come to the cylinder during operation. Guidening bands are mounted on the piston to support the main seal. The guidening elements are also selected according to the ambient conditions, like the main sealing element.

Sealing elements that prevent external leaks (rod seals) are mounted on the part called head (gland) on the cylinder. These elements serve as static and dynamic sealing elements. The most important condition for statically active elements is temperature and fluid type. The dynamically active ones are chosen depending on the ambient conditions such as the internal leakage main sealing element.

The selection of these elements varies according to climatic conditions. For very hot or very cold areas, for example, the choice of special sealing elements and the right combinations must be made.

MATERIAL SELECTION

It is essential to choose the right materials for the hydraulic cylinder to be efficient and long-lasting. Material selection is made according to the task of each part of the hydraulic cylinder. Material compatibility and weldability are investigated separately for welded parts. The parts that have coating or delicate processes on the surface must be selected correctly.

The basic components of hydraulic cylinder and their characteristics are as follows;

Rod (shaft) is the element which carries the force and moves linearly with the pressure formed inside the cylinder. This element carries the variable loads directly to the cylinder, so it is necessary to select the material with the right strength according to the incoming forces. AISI 1045, AISI 4140 materials are generally selected for our designs. The rod processed for surface roughness, resistance to corrosive effects and resistance to external impacts. Chrome and nickel plating is used for roughness and resistance to corrosive effects, while the surface is hardened by induction to a certain depth for impact resistance.

Cylinder Tube (bore / barrel) is the element which carries the pressure formed in cylinders. They are selected from materials which are resistant to variable pressures and have a long fatigue life. The main materials are St52-3 BK+S final heat treatment conditional, AISI 4140, 27SiMn. The inner surface of the tube should be very resistant to abrasion and the main body structure should be tough. The inner surface is rolled and burnished and allows the guidening-sealing elements to work.

Head (gland), is a part that is used to prevent external leaks and rod guidening elements that carry the guidening. It must be resistant to impacts and have a flexible structure. They are produced by casting or forging with special alloys.

Knuckle and Tube Head, these are the parts that the machine and cylinder are connected to each other. Extra strength is required. That’s why they are forged. In addition, their ability to be welded should be good.