一、概 述
孔隙度是岩石的重要性质之一，它定义为孔隙体积与岩石几何体积的比值，通常用百分数表示。这种油田水烃类物质占据的孔隙空间的大小，无论对合理评价油藏，还是对油藏进行工程施工都是必不可少的参数。
我们参考了大量的资料设计的气体孔隙度仪，具有结构简单、操作方便、测定速度快、性能稳定等特点，是岩心分析实验室必不可少的装置。
二、工作原理
气体孔隙度仪是测量体积的一种仪器，用它可以测定岩样的骨架体积和孔隙度体积，利用气体膨胀原理，即玻义尔（BoyLE）定律，已知体积的气体在确定的压力下向未知体积等温膨胀，膨胀后可测定终的平衡压力。平衡压力的大小取决于未知体积的大小，而未知体积的大小由玻义尔定律求得。
该仪器可用两种气体作为驱替介质，氮气和氦气。对于一般的砂岩可用氮气，对于较为致密的灰岩和孔隙较小的岩样可用氦气测定。用氦气的理由是：①微小的氦气（分子分子半径r=0.9A）作为介质能够进入与油藏岩石伴生的毛细管；②分子量低的氦气（M=4）对岩石具有较高的渗透能力；③岩石表面对氦气吸咐性较差。
根据玻义尔定律：气体的已知体积Vk与所测压力Pk下等温膨胀到未知室体积V中，膨胀后测量终平衡压力P这个平衡压力取决于未知体积量，未知体积可以用玻义尔定律求得。
三、仪器结构及各部件说明
本仪器是根据玻义尔定律设计的，所以等温很重要，故要求安装在非通气区，没有空气直接流通的室内实验台上，只要温度稳定在2%范围内，即可测得稳定的结果。
仪器有下列部件：
1．气源阀：供给孔隙计调节器低于1MPa氦（氮）气，当供气阀关闭时，调节器通过常泄，使压力保持恒定。
2．调节器：将1MPa的压力准确地调节到0.7MPa以下。
3．供气阀：连接0.7MPa以下压力的气体到标准室和压力计，它是标准室体积的上游极限。
4．标准室：已知体积室。
5．样品阀：能使标准室内0.7MPa压力的气体连接到未知室体积上去，它是标准室体积的下游极限。
6．放空阀：使末知体积中的初始压力为0MPa，同时又可以使平衡后的气体放入大气。
7．压力计：测量体系中气体压力，用来指示标准室的压力准确达到0.7MPa以下，并指示体系平衡的压力。
I. Overview
Porosity is one of the important properties of rock, which is defined as the ratio of pore volume to geometric volume of rock, usually expressed as percentage. The size of pore space occupied by hydrocarbon substances in oilfield water is an essential parameter for reasonable evaluation of oil reservoirs and engineering construction of oil reservoirs.
The gas porosity instrument designed by us with reference to a large number of data has the characteristics of simple structure, convenient operation, fast determination speed and stable performance, and is an essential device in the core analysis laboratory.
Second, the working principle
Gas porosimeter is an instrument for measuring volume, which can be used to measure the skeleton volume and porosity volume of rock samples. By using the principle of gas expansion, that is BoyLE's law, the gas with known volume expands isothermally to the unknown volume at a certain pressure, and the final equilibrium pressure can be determined after expansion. The equilibrium pressure depends on the unknown volume, which is obtained by Boyle's law.
The instrument can use two gases as displacement media, nitrogen and helium. Nitrogen can be used for general sandstone, and helium can be used for dense limestone and small pore rock samples. The reasons for using helium are as follows: ① tiny helium (molecular radius r=0.9A) can enter the capillary associated with reservoir rocks as a medium; ② Helium with low molecular weight (M=4) has high permeability to rocks; ③ The adsorption of helium on the rock surface is poor.
According to Boyle's law, the known volume Vk and the measured pressure Pk of gas expand isothermally into the unknown chamber volume V, and the final equilibrium pressure P is measured after expansion. This equilibrium pressure depends on the unknown volume, and the unknown volume can be obtained by Boyle's law.
III. Instrument Structure and Description of Components
This instrument is designed according to Boyle's law, so isothermal is very important. Therefore, it is required to be installed in an indoor experimental platform in a non-ventilated area without direct air circulation, and stable results can be obtained as long as the temperature is stable within 2%.
The instrument has the following components:
1. Air source valve: helium (nitrogen) gas below 1MPa is supplied to the pore meter regulator. When the air supply valve is closed, the regulator keeps the pressure constant through normal venting.
2. Regulator: Adjust the pressure of 1MPa to below 0.7MPa accurately.
3. Air supply valve: connect the gas with the pressure below 0.7MPa to the standard chamber and pressure gauge, which is the upstream limit of the standard chamber volume.
4. Standard room: a room with known volume.
5. Sample valve: It can connect the gas with pressure of 0.7MPa in the standard room to the unknown room volume, which is the downstream limit of the standard room volume.
6. Vent valve: the initial pressure in the unknown volume is 0MPa, and at the same time, the balanced gas can be released into the atmosphere.
7. Pressure gauge: it measures the gas pressure in the system, and is used to indicate that the pressure in the standard room is below 0.7MPa accurately, and to indicate the equilibrium pressure of the system.
南通立凯机电工程有限公司专业设计、制造、销售超临界流体设备和石油科研仪器。产品主要包括：
超临界二氧化碳萃取设备、超临界气凝胶干燥设备、超临界细微粒子制备装置、超临界清洗发泡装置、超临界抗溶剂结晶装置、高温高压磁搅拌反应装置、超临界相平衡仪等。
岩心自动剖切机、岩心钻取机、岩心钻切机、液氮冷冻钻取机、液氮冷冻切割机、疏松岩心装备装置、岩心端面切磨机、岩心端面切割机、台式切片机、切样机、岩矿切片机、磨片机、单、双盘金相岩相抛光机、颚式破碎机、自动研磨机、岩心快速洗油仪、填砂压实装置、人造岩心制作装置、含粘土人造岩心制作装置、岩心﹙油、水﹚抽空加压饱和实验装置、渗透率自动测定仪、气体渗透率测定仪、全直径岩心渗透率测定仪、克氏渗透率测定仪、氦孔隙度自动测定仪、气体孔隙度测定仪、全直径孔隙度测定仪、气体孔渗联测仪、致密岩心孔渗测定仪、全直径孔渗联测仪、高温覆压孔渗测定仪、岩心饱和度干馏仪、煤岩心测量系统、岩心饱和度干馏仪、全直径岩心饱和度测定仪﹙蒸馏法﹚、碳酸盐含量测定仪﹙表压式﹚、碳酸盐含量测定仪﹙数显式﹚、岩石比面测定仪、岩心流动试验仪、低渗敏感性评价仪、长岩心梯度流动试验仪、特低渗岩心启动压力梯度测量系统、岩心声波综合测试仪、岩心声电渗参数测定仪、岩心电阻率参数测定仪、多功能岩心驱替装置、润湿性测定仪、高压半渗透隔板仪、油、水相对渗透率测定仪、气液相对渗透率仪、高温高压相对渗透率自动测定仪、岩心孔隙铸体仪、岩心力学性能测试系统、长岩心物理模型、多功能综合驱油装置、多维多功能化学驱物理模拟系统、全自动长岩心双管试验装置、聚合物续凝实验装置、天然气水合物的形成及开采、蒸汽驱油试验装置、超临界CO2驱油实验装置、泡沫驱多功能物理模拟实验装置、微观驱物理模拟装置、多层长岩心驱替装置、油藏条件下多功能驱替系统、一维火烧油层实验装置、三维火烧油层实验装置、采油化学剂评价实验装置、天然气水合物抑制评价实验装置、微生物驱油试验装置、振动采油室内模拟试验装置、凝胶转变压力测定仪、全自动过滤因子测定装置、混相仪、动态结垢评价仪、微型蒸汽发生器、油水自动计量装置、油气水自动计量装置、油气水三相自动计量装置、岩心酸化流动试验仪、压裂酸化工作液动滤失仪、堵水调剖流动性能评价仪、支撑剂裂缝导流测试系统、酸蚀裂缝导流仪、酸岩反应旋转岩盘仪、智能高温高压页膨胀仪、高温高压失水仪、动态高温高压养护釜、井壁稳定性模拟实验装置、钻井液高温高压密度特性实验装置、高温高压动态堵漏模拟装置、地层流体高压物性分析仪、深井取样器、原油快速脱水器、原油动态结蜡仪、原油含蜡测定仪、铜板腐蚀试验仪、挂片动态腐蚀仪、活塞式高压配样器、活塞式储样筒、储样筒、岩心夹持器、多测压点岩心夹持器、电阻率岩心夹持器、声电渗岩心夹持器、高温高压岩心夹持器、全直径岩心夹持器、金属填砂模型管、长岩心模型、非金属填砂模型管、径向流岩心夹持器、碳酸盐测定夹持器、孔隙度测定夹持器、动滤失岩心夹持器、双渗模型、达西定律模型、平面径向流模型、一维线性流模型、水电模拟实验装置、ZR中间容器、HC活塞耐酸容器、有机玻璃容器、高压观察窗容器、高温高压反应釜、视窗反应釜、压力调节器、回压阀、手动计量泵、手摇泵、电动计量泵、高压恒速泵、恒压恒速泵、双缸气体增压泵、采样器、加氢高压微反装置、小型固定流化床反应装置、催化反应设备、液固非均相催化反应装置、催化剂反应活性评价装置。
高压水平阀、垂直阀、三通阀、四通阀、六通阀、单向阀、变丝接头、保护接头、死堵、接管压帽、卡环、仪表接头、高压快速接头、软管接头、取样器转样接头、内卡套过滤器、气瓶接头、手拧式快速接头、双卡套直通球阀、双卡套角式球阀、双卡套快开阀、软密封四通管接头、卡套式直通截止阀、卡套式直通节流止阀、卡套式角式截止阀、卡套式角式节流阀、卡套式角式截止阀、卡套式拧入管接头、卡套式焊接管接头、卡套式中间三通管接头、岩心夹持器专用皮套等。
客服1