【正文】 ship from the deck heavy machinery (winch), the bow doors, bulkhead valve, stern thruster, etc.。后來(lái)問(wèn)老師才知道不要求做三維制圖，也不用管缸，馬達(dá)等實(shí)體如何空間布置，只做系統(tǒng)圖和泵站圖，這才明白，所想與所要求的背道而馳。 將參數(shù)代入公式中，即： m in/1 4 01 2 Lq P ??? 但是有蓄能器補(bǔ)油，可以選擇 A10VS0100DR 1500r/min 時(shí)，流量 150L/min,功率 62 千瓦，尺寸 206X==63mm 液壓系統(tǒng)壓油管道推薦流速 36，壓力高，管道短，粘度小取大值； 液壓系統(tǒng)回油管道推薦流速 ； ② 給 快 開(kāi) 缸 供 油 的 管 子 ， 取 速 度 值 為 ，則d2=(4x127/1000/60/)189。 快進(jìn)時(shí)完成動(dòng)作時(shí)間 t6=V6/Q6 快進(jìn) =。 （ 9） 在矯直輥入口處安裝一彎頭壓直機(jī)，消除頭部鋼管的上翹。新的矯直技術(shù)也需積極開(kāi)發(fā)，如振動(dòng)矯直、高效高精度滾光矯直、液壓拉彎矯直、高精度壓力矯直，矯直過(guò)程的計(jì)算機(jī)控制、復(fù)合輥形的矯直技術(shù)以及復(fù)合轉(zhuǎn)轂矯直技術(shù) 2 等；在矯直理論研究方面應(yīng)該走出自己的道路，如材料強(qiáng)化影響的計(jì)算方法、變形能的測(cè)定及計(jì)算方法、等曲率塑性區(qū)長(zhǎng)度及深度對(duì)矯直質(zhì)量的影響，在矯直過(guò)程中克服殘留應(yīng)力影響的方法，減矯直過(guò)程的摩擦損失，最佳結(jié)構(gòu)參數(shù)的確定方法，斜輥的受力測(cè)定與計(jì) 算方法、熱處理軋材的矯直方法以及雙向旋轉(zhuǎn)矯直法等。并對(duì)主要非標(biāo)準(zhǔn)件進(jìn)行設(shè)計(jì)。制造新型高生產(chǎn)率的精整設(shè)備的任務(wù)首先是管材矯直機(jī)。 三． 液壓系統(tǒng)基本參數(shù)計(jì)算 液壓馬達(dá) ： 查 資 料 得 ： q= 5 T= Pw= ： 查資料得： 排量 q=,額定壓力 p=10mpa ,峰值壓力 Pmax=16MPa,轉(zhuǎn)速范圍 r=8400 額定輸出轉(zhuǎn)矩 T= 額定輸出功率Pw= Φ 300/180X20 3 個(gè) 30mm/S 大腔進(jìn)油，小腔出油 由流量計(jì)算公式： ???Aq 快進(jìn)時(shí)： Q3 快進(jìn) =A3 X v3= smsmm /????? ）（? ≈ 127L/min 快退時(shí)： Q3 快退 =A3` X v3= smsmmm /])()[4 3322 ??????（? ≈ 容積變化量 V3=A3 x L3= 32 1 4 1 3 0 0 mmm ??? ）（? = 。 快 進(jìn)時(shí)完成動(dòng)作時(shí)間 t7=V7/Q7 快進(jìn) =。==17mm ⑦ 給換輥裝置液壓馬達(dá) 供油的管子，取速度值為 3，因?yàn)轳R達(dá)轉(zhuǎn)速不同，所需流量不同，經(jīng)過(guò)計(jì)算它的流量范圍是 l/min，由于 換輥裝置液壓馬使用頻率不高，并且速度太高不安全，取Q7=100L/min 則 d7=(4x100/1000/60/)189。功率計(jì)算公式如下： P=? pP qP? () 式中： P電動(dòng)機(jī)額定功率； Pp液壓泵的工作壓力； Pq 液壓泵的流量； η 液壓泵的總效率，取η =。 選完型之后開(kāi)始畫(huà)閥臺(tái)，泵站圖。 hydraulic control part contains a variety of control valves, used to control the flow of oil, pressure and direction。 rather into the cylinder, making the latter subject to variations in the pump delivery due to changing workloads. Bleedoff circuits should not be used in applications where there is a possibility of the load running away. Types of Flow Controls Flow control valves fall into two basic categories: pressure pensated and nonpressure pensated. The latter being used where load pressures remain relatively constant and feed rates are not too critical. They may be as simple as a fixed orifice or an adjustable needle for free valve, although more sophisticated units may even include a check valve for free flow in the reverse direction. Use of nonpressure pensated valves is somewhat limited, since flow through an orifice is essentially proportional to the square root of the pressure drop across it. This means that any appreciable change in the work load would affect the feed rate. Pressure pensated flow controls are further classified as restrictor and bypass types. Both utilize a pensator or hydrostat to maintain a constant pressure drop across an adjustable throttle. The ByPass Typebines overload protection with pressure pensated control of flow. It has a normally closed hydrostat which opens to divert fluid, in excess of the throttle setting, to the tank. Pressure required by the work load is sensed 25 in the chamber above the hydrostat and together with a light spring tends to hole it closed. Pressure in the chamber below the hydrostat increase duo to restriction of the throttle and cause is to rise diverting any excess flow to tank when the difference in pressure is sufficient to overe the spring. This difference, usually 20 psi, is maintained across the throttle providing a constant flow regardless of the work load. Some horsepower saving is acplished in that the pump need operate at only 20 psi above work load pressure. Overload protection is provided by an adjustable spring loaded poppet which limits the maximum pressure above the hydrostat, causing it to function as a pound relief valve whenever work load requirement exceed its setting. The bypass flow control can only be used in a meterin circuit. If used for metering out, exhaust oil which could not get through the throttle would be diverted to tank permitting the load to run away. The Restrictor Type Flow Controlalso maintains a constant 20 psi differential across its throttle by means of a hydrostat. In this valve, the hydrostat is normally epen and tends to close off blocking all flow in excess of the throttle setting. In these units the work load pressure acts with a light spring above the hydrostat to hold it open. Pressure at the throttle inlet and under the hydrostat tend to close it, permitting only that oil to enter the valve that 20 psi can force through the throttle. Because of their tendency close off when flow tales to exceed the throttle setting, restrictor type valves may be used in meterin, meterout and bleedoff circuits. Unlike the bypass type , two or more restrictor valves may be used with the same pump since the excess pump delivery returns to tank through the relief valves. When placed in cylinder lines an integral check valve is optional to provide free flow for a rapid return stroke. One would not be required for valves placed in the main supply line, the tank line of a directional valve or when they are used in bleedoff circuits. Temperature Compensated Flow Control Valve Flow through a pressure pensated flow control valve is subject to change 26 with variations in oil temperature. Later design Vickers valves incorporate a temperature. Although oil flows more freely when it is hot, constant flow can be maintained by decreasing the size of the throttle opening as the temperature rises. This is acplished through a pensating rod which lengthens with heat and contracts when cold. The throttle is a simple plunger that is moved in and out of the control port. The pensating is installed between the throttle and its adjuster. This design also is available with a reverse freeflow check valve. Remote Flow Control Valves Remote flow control valves