These days, you will find that hydraulic tensioners are used in various workshops and also in any production environment. There are many different varieties of hydraulic tensioners available however the operating principle for all of them are more or less the same. An accurate axial load is applied to fasteners by using high-pressure hydraulic oil and once the right pressure is reached, the operator uses a small bar so that a nut is placed in its position. Once the nut is properly positioned, hydraulic pressure is released so that axial load is transferred to the fastener.
Let us discuss about three different varieties of hydraulic tensioners in the following paragraphs.
- Fixed hydraulic tensioner
This variety of hydraulic tensioner is quite compact in size and easy to handle. At the same time, it is much more affordable too. In this type of tensioner, for any one thread size, each tool is designed. All that the operator does is that he puts the bridges just over the nut and thereafter threads the load cell over the stud till it makes a contact with the bridge. After that the operator connects the hoses and follows necessary steps as mentioned in the operating instructions of the tensioner.
- Variable hydraulic tensioner
Here by using the hydraulic load cell, tensioning can be achieved on a number of thread types and sizes of threads. This kind of models also have side hydraulic ports so that you can get the lowest installed height. Here, the operator will place the bridge as well as load cell just over the nut. After that he will thread the separate puller bar onto the stud so that it comes in contact with the load cell. After that the operator connects the hoses and thereafter continues to follow the steps that is mentioned in the operating instructions which was noted earlier.
- Hydraulic nut
This hydraulic nut will replace the nut which was used normally and will remain with the stud. Since, this is very compact system, it will not need any additional stud length. All that the operator does here is screws the hydraulic nut down tightly and connects with the hydraulic hoses. As the necessary pressure is achieved, the operator will either screw down a collar or he will insert shims which is designed for this application.
Usually, you will find that hydraulic system is mainly used on such applications where high loads are used and angular vibration is needed. Such tensioner will need more engine space for proper functioning.