In the last issue of《Dimensional classroom》In the column，Xiaowei took everyone to know Wittgen. HT 22 Introduction of quick-change tool holder，Current period《Dimensional classroom》Xiaowei will continue to bring to his fans. HT 22 Maintenance and replacement skills of quick-change tool holder。

Wittgen HT 22The contact surface between the upper and lower parts of the quick-change tool holder is prismatic，Than HT 11 The contact surface of the shoe is increased by nearly 70%，So that that mil force can be more reliably transmitted to the low tool holder。The upper tool apron completely covers the lower tool apron.，Prevent burrs from being generated on the lower tool holder，O as to ensure that the upper tool holder can be simply and conveniently replaced under the condition that the base is not required to be trimmed.。

If the shoe is damaged or worn，ThenIt needs to be replaced in time.。Be careful when replacing the cutterbed，It must be carried out in accordance with the specifications using the correct tools.，And strictly follow the maintenance cycle.。If the shoe is adequately maintained，Proper replacement may only take a few minutes.。Click on the video below to see the steps，In this video, Xiaowei suggests collecting it and watching it again and again.！

The cutterbed must always be in good condition，Therefore, it is recommended to check the wear state several times a day.。Before disassembly and assembly，Rotate the milling drum to the proper position with the milling drum slow rotation device，O that the cutter and the cutter holder can be easily disassembled and assembled。

The detailed steps for maintenance and replacement of the cutterbed are as follow：

1. Remove the asphalt residue at the entrance of the fastening bolt，Then lever off the sealing cap using a screwdriver。Save time on cleaning with the cap plugs supplied by Wirtgen，Thus speeding up the replacement.。

2. Clean the fastening bolt，Loosen the bolt with an Allen key and remove completely，The upper shoe can be pulled out of the lower shoe.。Threads and bolt heads may be deformed by high loads during cutting，Therefore, to prevent damage to the threads in the lower shoe,，Fastening bolts shall not be reused。

Tips: When the bolts are removed，The wrench shall be inserted into the bottom of the bolt，To prevent damage to the bolts。Do not use worn tools.！

3. The inside diameter of the lower shoe and the upper shoe mounting hole must be carefully cleaned during replacement，And check for damage。After thorough inspection and cleaning，Make sure that there is no milling material left in the lower shoe.，And that contact surface of the upper tool apron and the lower tool apron can be tightly fit without gaps.。

4. The contact surface of the lower shoe should be flat and free of damage。If the contact surface is in good condition，The tool apron seal ring is sleeved on the new tool apron handle.。

5. Apply high temperature resistant grease to the handle of the upper tool apron（Up to 100 °C），And then that tool handle is arrange in the lower tool hold;。The grease has the function of sealing and preventing the tool holder from being rusted.，It is also conducive to the smooth disassembly and assembly of the tool holder.。

6. At the same time, apply high temperature grease on the fastening bolt，Then place the bolt in the inner diameter of the thread for approximately three turn，Use a torque wrench to tighten the fastening bolts to 500 Nm Torque。（Notice：If a large amount of force is required to tighten the bolt，The thread must be re-milled on the lower tool holder with a thread milling cutter。）

Tips: Never use fastening bolts that have already been used！Only use a manual torque wrench to tighten the hexagon bolt。

7. Knock test shall be carried out after tightening the fastening bolt，Use 1Kg Knock the contact part of the tool apron with a copper hammer，Check if it can be tightened further。After that，The tightening bolts must be rechecked with a torque of 500 Nm。

8. Fit the cover plug on the fastening bolt。

9. Finally，Use a copper hammer to install the tool。

Tips: Used for the first time（Approx. 10 working hours）After，The hexagon bolts must be retightened to 500 Nm Torque； Then ，Every 500 working hours（500 hours、1000 hours、1500 hours）Tighten once。

《Dimensional classroom》It is a video column produced by Wittgen China Technology and Training Center to introduce equipment operation and precautions.，Launch on a regular basis，I hope you will continue to pay attention.。In addition，If Uyghur fans have questions they want to know，You can also leave us a message.。