In the working process of the underground loader, if the oil pressure is lower than 0.2MPa, stop the machine immediately to find out the cause, and continue to work after troubleshooting, otherwise it will cause serious mechanical accidents such as tile burning and cylinder pulling. Generally speaking, what are the reasons for the low oil pressure of the loader?

井下裝載機(jī)的機(jī)油壓力過(guò)低的原因：

The reasons for low oil pressure of underground loader are as follows:

①機(jī)油油量不足：若機(jī)油油量不足，會(huì)使機(jī)油泵的泵油量減少，導(dǎo)致機(jī)油壓力下降，加劇曲軸與軸承、缸套與活塞的磨損。而如果發(fā)動(dòng)機(jī)溫度過(guò)高，不但加速機(jī)油老化、變質(zhì)，也容易使機(jī)油變稀，導(dǎo)致油壓下降。

① Insufficient oil quantity: if the oil quantity is insufficient, the oil quantity of the oil pump will be reduced, resulting in the decrease of oil pressure, and aggravating the wear of crankshaft and bearing, cylinder liner and piston. If the engine temperature is too high, it will not only accelerate the aging and deterioration of the oil, but also make the oil thinner, resulting in the decrease of oil pressure.

②機(jī)油泵停轉(zhuǎn)或泵油量不足：如果機(jī)油泵的驅(qū)動(dòng)齒輪與驅(qū)動(dòng)軸的固定銷(xiāo)斷裂或配合鍵脫落，以及機(jī)油泵吸入異物而將泵油齒輪卡住，都會(huì)使機(jī)油泵停止運(yùn)轉(zhuǎn)，機(jī)油壓力也隨之降為0。

② The oil pump stops running or the pump oil quantity is insufficient: if the fixed pin of the drive gear and the drive shaft of the oil pump breaks or the matching key falls off, and the oil pump sucks foreign matters and blocks the oil pump gear, the oil pump will stop running and the oil pressure will drop to 0.

③機(jī)油濾油器堵塞：當(dāng)機(jī)油因?yàn)V油器堵塞而不能流通時(shí)，設(shè)在濾油器底座上的安 全閥就被頂開(kāi)，機(jī)油便不經(jīng)過(guò)濾而直接進(jìn)入主油道。如果安 全閥的開(kāi)啟壓力調(diào)得過(guò)高，濾油器被堵塞時(shí)，安 全閥就不能及時(shí)打開(kāi)，于是機(jī)油泵壓力升高，主油道供油量減少，引起油壓下降。

③ Oil filter blockage: when the oil cannot flow due to the blockage of the oil filter, the safety valve on the base of the oil filter will be pushed open, and the oil will directly enter the main oil passage without filtering. If the opening pressure of the safety valve is adjusted too high and the oil filter is blocked, the safety valve can not be opened in time, so the oil pump pressure increases and the oil supply quantity of the main oil passage decreases, causing the oil pressure to drop.

④回油閥損壞或失靈：若回油閥彈簧疲勞軟化或調(diào)整不當(dāng)，閥座與鋼珠的配合面磨損或被臟物卡住而關(guān)閉不嚴(yán)時(shí)，回油量便明顯增加，主油道的油壓也會(huì)隨之下降。

④ The oil return valve is damaged or out of order: if the spring of the oil return valve is fatigued and softened or improperly adjusted, the mating surface of the valve seat and the steel ball is worn or stuck by dirt, and the valve is not closed tightly, the oil return volume will increase significantly, and the oil pressure of the main oil passage will also decrease.

一般來(lái)說(shuō)，如果井下裝載機(jī)的調(diào)壓閥設(shè)定油壓低，機(jī)油就不能有效地輸送到各潤(rùn)滑部位，從而發(fā)生機(jī)械故障。如果油壓過(guò)高，就會(huì)增加油耗，給機(jī)油泵和潤(rùn)滑部位增加負(fù)荷，損壞油路密封件并引發(fā)機(jī)油泄漏。

Generally speaking, if the set oil pressure of the pressure regulating valve of the underground loader is low, the oil can not be effectively delivered to the lubricating parts, resulting in mechanical failure. If the oil pressure is too high, it will increase the oil consumption, increase the load to the oil pump and lubrication parts, damage the oil seal and cause oil leakage.