橡胶密炼机混炼过程中的节能

本文就橡胶密炼机混炼过程中,胶料在密炼室中的分散与混合的作用,分别阐述了节能的途径。提高混合效率方面提出了适当增加短棱的长度;适当增加长棱的螺旋角;改善转子表面的粗糙度;在转子外表面增设分流元件;改变转子的剖面形状;改变密炼室内壁结构。提高分散效率方面提出了提高上顶栓的压力;增大填充系数;控制密炼室壁与转子的温度;改变加料温度;改变加料顺序;转子外表面增设分流元件;密炼室内壁设置分流元件等。     

切线型转子密炼机的改进

介绍了卡特·布勒斯公司对切线型转子密炼机的改进。转子方面,主要加大了转子翼顶宽度;密炼室方面,把密炼室两侧的周边冷却孔扩展到压砣颈喉部位。此种方法改造适用于各种品牌的密炼机。改造后不但混炼效果好,而且改造投资也较少。     

同步同向转子密炼机性能的研究

首次提出同步同向转子密炼机的混炼原理,并通过在Ｘ（ Ｓ） Ｍ－ １ ．７ 同步同向转子密炼机上的实验来研究和分析同步同向转子对混炼过程的影响。     

对同步转子密炼机混炼各种胶料的性能的研究

同步转子密炼机是８０年代末开始应用于橡胶工业的一种新型炼胶设备。它较大程度地提高了混炼胶质量和混炼效率，尤其使混炼胶的均匀性有了极大的改善，是剪切型转子密炼机中的佼佼者，有着广阔的发展前景。本文通过描述在Ｘ（Ｓ）Ｍ－ｌ．７型同步转子（ＺＷ－１型）密炼机上混炼五种不同用途的胶料，以探讨同步转子密炼机对各种胶料的混炼性能。     

联锁式转子密炼机的最新进展

联锁式转子密炼机的最新进展ＢｒｏｗｎＣＪ著李贵君摘译涂学忠校最近几年,联锁式转子（ＩＲ）密炼机已发展成为优秀的橡胶混炼设备,主宰了高质量胶料生产的市场,已成为新建橡胶工业制品厂密炼车间选用的设备。尽管轮胎胶料的混炼在传统上一直沿用切向转子（ＴＲ）密炼...     

对同步转子密炼机混炼各种胶料的性能的研究

同步转子密炼机是８０年代末开始应用于橡胶工业的一种新型炼胶设备。它较大程度地提高了混炼胶质量的炼效率。尤其使混炼胶的均匀性有了极大的改善，是剪节型转子密炼机中的佼佼者，有着广阔和发展前景。本文通过描述在Ｘ（Ｓ）Ｍ－１．７型同步转子密炼机上炼五种不同用途的胶料，以探讨同步转子密炼机对各种有胶料的混炼性能。     

转子转速和薄通次数对胎面胶结构与性能的影响

根据普通密炼机一段混炼工艺和密炼结合开炼机低温混炼工艺,通过硫化特性、门尼黏度、Payne效应、基本力学性能及耐疲劳性能和耐磨耗性能等测试,研究了密炼机转子转速和开炼机薄通次数对胎面胶结构与性能的影响。结果表明,改变密炼机转子转速对硫化胶的耐疲劳性能和耐磨耗性能影响较大,随着转子转速的增加,胶料的疲劳寿命先下降后提高、耐磨耗性能逐渐上升;改变薄通次数对门尼黏度、Payne效应和基本力学性能影响较大,但对疲劳寿命和耐磨耗性能的影响不明显,薄通15次胶料的门尼黏度、Payne效应和基本力学性能明显下降;密炼结合开炼机低温薄通工艺的混炼效果优于普通密炼机一段混炼工艺的混炼效果。     

同步转子密炼机

同步转子密炼机是美国法雷尔公司于１９８０年开发的，１９８８年正式投放市场，是目前密炼机产品的热门货。我国有几家大轮胎公司先后引进了Ｆ３７０（或Ｆ２７０）同步转子密炼机，投产后均获得明显的经济效益。同步转子密炼机用的同步转子有如下特点：①前后转子的速度相同，因此在操作时转子的温度分布是均匀的。②同步转子的长、短棱是平行的，分别排列在同一侧，这可使胶料在密炼室中流道畅通，流动性好；③当前后转子棱的方向呈垂直方向时，两转子之间出现最大的空隙，使胶料加速进入密炼室，既可缩短进料时间，又可使混炼均匀；当前…     

X(S)M-50/40型密炼机

大连橡胶塑料机械厂根据橡胶塑料行业的要求研制了X(S)M-50/40型密炼机。既能用于橡胶的混炼塑炼,也可用于塑料的加工。密炼室容量50升;工作容量30升;转子的转速为40转/分;主传动电机功率为95瓩。机器具有钻空式密炼室,下落式卸料门,与物料接触之工作表面全部镀硬铬。采用封闭电动机,     

填充系数对啮合转子密炼机混炼性能的影响

填充系数（β）是密炼机一次装胶容量与混炼室总容积之比,反映密炼机装胶料量的多少．是密炼机相对容易控制的工艺条件。β取值大小不仅直接影响密炼机消耗的最大功率、生产能力、单位能耗、混炼时间和排胶温度,还将影响混炼胶质量（物理机械性能和分散度等）;其次还会影响机台的正常使用。因此,研究填充系数（β）对混炼过程的影响十分必要。     

橡胶的摩擦性能对其加工的影响

介绍了橡胶加工中研究生胶与金属表面摩擦性能的意义和进展。由微观和唯象分析建立了橡胶粘附摩擦的理论模型。通过对模型的分析和实验验证,提出了提高加工设备生产能力的新途径：(1)密炼机、挤出机、压延机温度控制采用温水冷却，使其处于最佳工作状态；(2)通过合理选择设备材料，改变材料表面能来增大胶料与它们之间的摩擦力；(3)在压力较大的条件下，在密炼室或机简内壁与轴线同方向加工浅的光滑槽可明显改善加工性能。     

Effect of adding different silane coupling agents on metal friction and wear in mixing process

The function of silane coupling agent in rubber mixing field is to combine inorganic matrix with rubber organic matrix. Silica is commonly used in the rubber mixing field to strengthen rubber. The size and amount of silica aggregates in the mixing process are important factors affecting the wear of the mixing chamber. The wear of the mixing chamber would lead to a increasing gap between the mixer chamber and the rotor, which caused the mixing efficiency reducing. It also affected the dispersion effect, then affected the mechanical and physical properties of the vulcanized rubber. In this paper, the effects of rubber compound on metal friction and wear were studied by using four silane coupling agents commonly used in rubber mixing field. The experiment was carried out at 15°C, and the attention should be paid to drying during sample preparation to avoid the deviation of the experiment caused by hydrolysis of silane coupling agent. The results showed that silanization reaction occured between silica and silane coupling agent in the mixing process. The mixing temperature was usually maintained at 145 to 155°C for 1 min in the mixer, and the silanization reaction rate was the fastest during this time. We took this rubber compound as the research object and studied the friction and wear of the rubber compound on the mixing chamber in the mixing process. The products of the silylation reaction are alcohol and water. This paper studies the corrosion and abrasion of the mixing chamber by water at high temperatures. In the mixing process, abrasive wear was the main wear form, but the corrosion wear caused by high temperature steam still occupied a large proportion.     

A comparison of the effects of traditional and wet mixing processes of rubber on metal friction and wear

Prolonged operations of mixers cause wear of mixer rotors and chamber walls and affect the clearances between the rotors and chamber walls, which reduce the mixing effect, weaken the dispersion of the packing, and affect the quality of rubber products. In this study, the effects of traditional mixing and wet mixing on the friction and wear of the chamber, and the properties of rubber were compared by using 60 phr of a silica natural rubber formulation system. The results show that a silanization reaction occurs between silica and the silane coupling agent during the mixing process and that the reaction rate is fastest when the temperature of the mixing chamber is maintained between 145 and 155°C for 1 min during the mixing process. The products of silanization reaction are ethanol and water; the water vapor that forms at high temperatures corrodes the mixing chamber of the internal mixer and aggravates wear and tear. Due to the high dispersion of silica during wet mixing, the silanization reaction is more complete and water vapor is produced at a high temperature. Hence, the rubber compound obtained by wet mixing has more significant wear on the mixing chamber.     

Internal mixing: A practical investigation of the influence of intermeshing rotor configuration and operating variables on mixing characteristics and flow dynamics

This paper deals with the measurement and interpretation of pressures and temperatures produced by the mixing of a rubber compound in the chamber of an internal mixer equipped with interlocking rotors. Pressure transducers and infrared/fiber optic temperature sensors were sited flush with the inner surface of the mixing chamber of a Francis Shaw KO Intermix of 2 L chamber volume. The variation of pressure with transducer position In the chamber wall and with rotor position was measured for selected fill factors and rotor speeds at “equilibrium” conditions (quasi-static power requirement for the mixer) and at intervals during a complete mixing cycle. Two rotor designs were studied. Interpretation of the results was carried out with reference to biconical rotor rheometer measurements on the mixed rubber compounds and by reference to four regimes of viscoelastic behavior identified for two-roll mill mixing. A basic flow analysis was carried out by use of the lubrication approximation in conjunction with an isothermal power-law model.     

Laminar mixing of shear thinning fluids in a SMX static mixer

Flow and mixing of power-law fluids in a standard SMX static mixer were simulated using computational fluid dynamics (CFD). Results showed that shear thinning reduces the ratio of pressure drop in the static mixer to pressure drop in empty tube as compared to Newtonian fluids. The correlations for pressure drop and friction factor were obtained at Re_MR?100. The friction factor is a function of both Reynolds number and power-law index. A proper apparent strain rate, area-weighted average strain rate on the solid surface in mixing section, was proposed to calculate pressure drop for a non-Newtonian fluid. Particle tracking showed that shear thinning fluids exhibit better mixing quality, lower pressure drop and higher mixing efficiency as compared to a Newtonian fluid in the SMX static mixer.     

Molecular dynamics study of epoxy/clay nanocomposites: rheology and molecular confinement

To investigate the effect of nanoparticles on molecular confinement, epoxy/clay nanocomposites in 6?% wt were prepared by low shear mixer and ultrasonication methods. According to the XRD results, high energy sonication can significantly increase the intergallery space compared to that of the low shear mixer and, therefore, provide more interfacial area for polymer-particle interaction. Rheological measurements, including dynamic mechanical moduli, continuous relaxation spectrum and zero-shear viscosity, were carried out in the linear region to reveal the solid-like characteristics induced in the pure epoxy. The longest Rouse relaxation time, which was determined from the value of zero-shear viscosity, was employed to study the segmental friction. It is clear that the chain relaxation process was slowed by the polymer-particle interactions, which created very high monomeric friction. We introduce the ratio of monomeric friction coefficients (??_nano/??_epoxy) as the strength of immobilization to correlate the increasing elasticity, longer relaxation time and molecular confinement quantitatively. Because more monomers can be immobilized on a clay surface due to their strong affinity, the friction ratio increased to 359.48 for the sonicated sample, whereas weak polymer-particle affinity resulted in much lower growth, with a friction ratio of 2.11 for the low shear mixing method.     

Improving mixing performance by curved-blade static mixer

This article addresses design modification to a flat-blade static mixer to enhance mixing performance. The static mixer elements used in this work consist of four blades with curvature made to intensify turbulent-like flow, while reducing the pressure drop. The blades were mounted on a cylindrical housing with 45° rotation relative to the axial direction. The mixer assembly was used in three different arrangements of 8, 10, and 14 elements for a range of Reynolds number between 600 and 7,000. The coefficient of variance (COV) of samples was used to measure the mixing quality. The curved-blade mixer provides considerable improvement in mixing quality compared with the flat-blade mixer and comparable to the SMX mixer. Compared with the flat-blade static mixer, the new design reduces the COV by up to about 50%. This effect is more pronounced when the number of mixing elements increases. Furthermore, the friction factors for the modified mixer, obtained at a wide range of Reynolds number, were apparently smaller than those for the flat-blade, SMX, and SMV mixers. The correlation presented for the friction factor, when all mixer arrangements and aspect ratios were considered, supports the experimental data with ±15% deviation.     

The design and performance of a vane mixer based on extensional flow for polymer blends

A new laboratory‐scale mixing device called the “Vane Mixer” was designed, built, and tested. The vane mixer consists of three vane plasticizing and conveying unit. In comparison with the existing laboratory mixers, material flow in this vane mixer is characterized by a high contribution from extensional flow. As the mixer has mixing chamber of very simple geometry, the cleaning is very easy and the material lost is very small. The influences of mixing time and rotor speed on dispersed phase size were characterized and discussed. Morphology data on model immiscible polystyrene/high density polyethylene (PS/HDPE) blend have proved the high distributive and dispersive mixing efficiency. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41551.     

The effect of mixer properties and fill level on granular flow in a bladed mixer

The discrete element method was used to study the effect of mixer properties and fill level on the granular flow of monodisperse, cohesionless spheres in a bladed mixer. For fill levels just covering the span of the blades, a three‐dimensional (3‐D) recirculation zone develops in front of the blades, which promotes vertical and radial mixing. Increasing fill level reduces the size of the recirculation zone, decreases bed dilation and hinders particle diffusivities. However, above a critical fill level, the behavior of the particles within the span of the blade is found to be invariant of fill level. At low‐fill levels, the pressure within the particle bed varies linearly with bed height and can be approximated by hydrostatics. At higher fill levels, a constant pressure region develops within the span of the blades due to the angled pitch of the blades. Cylinder wall friction is shown to significantly influence granular behavior in bladed mixers. At low‐wall friction, the 3‐D recirculation zone observed for high‐wall friction conditions does not develop. High‐wall friction leads to an increase in convective and diffusive particle mixing. Shear stresses are shown to be a function of wall friction. Blade position along the vertical axis is shown to influence flow patterns, granular temperature and stress. The effect of increasing the mixer diameter at a constant particle diameter was also studied. When the mixer diameter is larger than a critical size such that wall effects are minimized, the observed granular behavior follows simple scaling relations. Particle velocities and diffusivities scale linearly with mixer size and blade speed. Normal and shear stress profiles are found to scale linearly with the total weight of the particle bed. © 2009 American Institute of Chemical Engineers AIChE J, 2010     

Design and characterization of a Low-pressure-drop static mixer

Four-blade static mixer was designed for inline mixing of Newtonian fluids at Reynolds numbers from 700 to 6800. The mixer consists of four equally spaced blades mounted on cylindrical housing with 45° rotation relative to the circumference. It was tested in three different compartments of 6, 8, and 10 mixing elements; each element rotated 45° relative to the adjacent one. Multipoint sampling was used to measure concentration downstream the mixer. The mixing quality was measured by the coefficient of variance (CoV). The CoV decreases as the energy input per unit mass increases. This effect is more pronounced when the number of mixing elements increases. For the case of 10 mixing elements, a good mixing performance (typically more than 95% mixedness or CoV < 0.05) achieved, although a marginally good mixing performance could also be achieved by eight mixing elements. The friction factors were correlated as f = C₁/Re + C₂/Reⁿ with an average deviation of ±10% from experimental data. Furthermore, experimental friction factors were compared with existing models. For a wide range of Reynolds numbers, the friction factors are apparently smaller than those from SMV, KMX, and baffle-type static mixers. © 2018 American Institute of Chemical Engineers AIChE J, 65: 1126–1133, 2019