裝載機(jī)氣缸套穴蝕的原因

裝載機(jī)/氣缸體及氣缸套的穴蝕破壞，引起裂紋甚至產(chǎn)生通孔，導(dǎo)致冷卻水進(jìn)入氣缸和機(jī)油中，顯著降低了柴油機(jī)的壽命及工作可靠性。那么，引起山東裝載機(jī)氣缸套穴蝕的原因有哪些呢？

裝載機(jī)產(chǎn)生穴蝕的主要根源是氣缸套的振動(dòng)。當(dāng)活塞到達(dá)上止點(diǎn)時(shí)，側(cè)壓力的作用方向發(fā)生變化，活塞從缸套的一面橫擺到對面，出現(xiàn)了活塞擺的現(xiàn)象。由于活塞與缸套之間留有熱間隙，所以活塞的擺動(dòng)是有沖擊性的。這種沖擊引起缸套的強(qiáng)烈振動(dòng)。當(dāng)缸套壁振動(dòng)時(shí)，水腔中發(fā)生交替的拉伸和壓縮，從而使外壁附近水域中產(chǎn)生局部的高壓和真空泡。在高真空的作用下，冷卻水蒸發(fā)成氣泡，有的真空泡和氣泡發(fā)生在氣缸套外壁微小的針孔中，或在振動(dòng)的作用下被擠入針孔。當(dāng)真空泡或氣泡受到高壓沖擊而破裂時(shí)，就在破裂區(qū)附近產(chǎn)生壓力沖擊波，其壓力可達(dá)數(shù)十大氣壓并沖擊氣缸外壁，這樣頻繁的反復(fù)沖擊，就使缸套表面急劇損壞。
The main source of Shandong loaders produce cavitation is vibration cylinder liner. When the piston reaches top dead center, the direction of the lateral pressure changes, the piston from the cylinder liner placed in the opposite side of the cross, appeared piston swing phenomenon. Since the gap is left between the piston and cylinder heat, so there is a swing piston shock resistance.This impact caused a strong vibration liner. When the liner wall vibration, water chamber occurred alternately stretching and compression, so that the generated partial pressure and vacuum bubble

wall nearby waters. Action under high vacuum, the cooling water evaporates into bubbles, some vacuum bubble and the bubble generation in the outer wall of the cylinder liner tiny pinholes, or under the action of vibration is extruded into a pinhole. Really vacuoles or bubbles burst when subjected to high voltage shock, it creates a pressure shock wave in the vicinity of the rupture area, up to tens of atmospheric pressure and the impact of the cylinder wall, so often repeated impact, it makes a sharp liner surface damage.

為了防止裝載機(jī)穴蝕，目前常用的方法是減小氣缸與活塞之間的間隙，從而減小缸套的振動(dòng)；采用長的活塞裙部；加大冷卻水流速，改進(jìn)水流方向及冷卻系的結(jié)構(gòu)；增加氣缸套的支承剛度；改進(jìn)氣缸套的材料及工藝，以提高其抗穴蝕能力等。
In order to prevent cavitation Shandong loaders, the most commonly used method is to reduce the gap between the cylinder and the piston, thereby reducing the vibration of the liner; with long piston skirt; increase the cooling water flow rate, improve the flow direction and Cooling structure; increase the cylinder liner bearing stiffness; improved cylinder liner materials and processes in order to improve its anti-cavitation capabilities.