手提式切石机消音锯片的制法

<正>原使用手提式切石机切割石材时,作业产生的噪音成为一大问题。因此,迫切需要开发出诸多噪音小的切锯片。这些锯片制作有用钎焊或焊接固定同时烧结和别的烧结法形成的磨粒层刀头的方法,其中同时烧结法适合批量制作,而且磨粒层固定强度高。消音锯片现有夹层复合型和激光切缝型。就夹层复合型消音锯片而言,由多枚金属圆片相互复合的现已研发出多品种,直径在100～1800mm范围内。这类品种有(1)在两块钢质圆片间设置铜或铜合金的中间层,     

Φ700～1600mm复合材料消音金刚石锯片基体的研制

正专家点评:该项目对原有设备进行改造,从改变锯片的结构入手,自行研发出新一代高性能环保消音型复合材料金刚石锯片基体,降低了锯片切割时产生的高频部分噪音,达到人体所能承受的范围。同时能极大地降低锯片振动,减少切割崩边,提高切割精度。设备改造水平得到显著突破,在工艺革新道路上迈出了强而有     

金刚石复合消音锯片点焊关键控制技术

<正>金刚石锯片作为一种切割工具广泛应用于各种领域。锯片在加工过程中,由于其高速旋转并与空气或工件相互作用,将产生较为尖锐的噪声,不仅危害操作者及周围其他人的身体健康,而且噪音产生的振动,直接影响到锯片的切割精度。根据其产生原因,主要分为空气动力性噪声、锯片振动噪声、锯片切割冲击辐射噪声和锯片与工件摩擦噪声四类,其中降低锯片噪声最为有效的是降低锯片振动噪声,     

自动化点焊机的研究与开发

对用于复合消音金刚石锯片基体焊接的电阻点焊机进行了自动化的研究开发，采用现场总线技术实现设备的集中管理，对其全自动工作台主要构成机构中的旋转伺服机构、进给伺服机构和上升下降机构进行了设计，使用PLC可编程控制器为控制中心，对其系统控制程序组成及工作台主程序流程进行了简述。使用自动化点焊机后，减少了人工劳动强度，提高了自动化水平以及复合消音金刚石锯片基体焊接产品品质。     

一种高效消音圆盘锯问世海外

普通圆盘锯是切割石材等硬质材料的重要切具。但圆盘锯在使用中尚存在一大缺陷，长期困扰着石材加工企业，这就是锯在切石过程中产生刺耳的巨大噪音污染，这不仅有害于操作人员的身心健康，也严重影响周边地区人们的正常生活。近来，海外一公司推出了一种结构新颖的高效消音圆盘锯。     

金刚石干切圆锯片热应力和离心力耦合分析

本文建立了干切圆锯片有限元分析模型，用热应力和离心力相互耦合的分析方法，对圆锯片在高速旋转切削时锯片基体应力和应变进行了计算，分析了工作中圆锯片基体应力、应变分布规律，探讨了圆锯片基体各种结构参数对工作中基体应力及变形的影响。分析结果表明，锯片的离心力对锯片产生有利的刚化作用，能在一定程度上减小锯片切削热引起的切向变形和应力，在相同的栽荷作用下，基体开有小圆孔的锯片能有效的降低锯片的径向变形，径向变形量减小19．8％左右，但基体开散热圆孔对减小锯片切向变形量和水槽底部应力并无贡献。     

高层建筑钢筋混凝土锯切技术的应用研究

结合工程实例,介绍金刚石盘式锯片切割、金刚石链锯切割及金刚石筒锯钻切三种常见工艺在高层建筑钢筋混凝土结构切割工程中的运用情况,从工作效率、切割面平整度、噪音及振动、"过切"问题、高空作业安全性等方面对三种工艺进行了对比分析,并提出了施工的意见与建议,对今后的高层建筑钢筋混凝土锯切施工工程具有重要的借鉴意义。     

浅述金刚石圆锯片基体张力处理技术

1引言 金刚石锯片被广泛应用于石材开采切板、建材切割、工程施工等领域,在使用过程中,基体处于高速旋转的工作状态,受离心力、切削力、热应力等多种载荷作用,局部会形成不同的应力区,从而可能会导致轴向变形,或者切割时会发生锯片抖动或跳动的现象.这种不稳定现象会导致切割对象切面不齐整、切缝超宽,造成材料浪费或者报废,同时也会影...     

混凝土锯切机锯片噪声产生机理与改进措施

混凝土锯切机在作业时,金刚石锯片会产生严重的噪声和振动,不仅对周围的环境造成噪声污染,还会影响工作人员的身体健康。本文对金刚石锯片的噪声产生机理进行了描述,包括切削噪声,振动噪声和空气动力学噪声的机理分析。在降噪改进措施的描述中,主要针对优化锯切参数、改变锯片结构、增加夹盘直径并安装金属橡胶以及喷水处理等技术进行了叙述。     

供热系统中喷射式换热器的消音减振装置

本文介绍了一种喷射式热交换装置的消音、减振及整流机构,由依次相互连通的补偿器、直管、柔性接头、弯管和消音止回阀组成。该机构连接在喷射式热交换装置的输出端,可以有效降低因两相流向单相流混合转变时产生的振动和噪音。     

A stress calculation model for the 3D borehole slotter

A stress calculation model is proposed for a new stress measurement device called the 3D borehole slotter. This instrument allows the calculation of the 3D in situ stress tensor in a single borehole without the need for a drill on the site at the time of the measurement and without bonding strain gauges at the borehole wall. The 3D borehole slotter requires cutting half moon shaped slots with different orientations at a borehole wall using a small diamond impregnated blade and monitoring the strains which are relieved normal to the slot. This paper shows that combining six slots cut on the borehole wall with one to three slots cut parallel to the borehole axis and five to three cut with a 45° angle, allows the calculation of the in situ stress tensor. The optimal slot combination is determined and 3D finite element analyses are used to evaluate the degree of stress relief normal to the slot at the strain sensor location and also to estimate the strains induced parallel to the slot by this local stress relief. The results obtained from these analyses are then used directly in the stress calculation model.     

Principles of diamond tool technology for sawing rock

In a rock sawing operation, a single diamond particle acting as a sliding indenter expends energy by generating compression in the rock in the form of a ‘stress epicentre’ through the action of confined crushing: this compression causes the rock fracture mechanism. It is not a cutting operation per se—indeed sharp diamond particles can be a liability. The sawing requirement is for a high strength, high heat resistance indentor, with a potential for displacement that is compatible with that of the rock. Currently used tests for rock strength do not indicate energy consumption, but the Shore and Brinell hardness tests are relevant. However, the consumed energy is predictable from a new index of rock strength, called Brook hardness, which has been specifically developed for sliding diamond indenters. The ‘stress epicentre’ is located with reference to the diamond indenter through a force vector which is stable for all circular sawing velocities, but it changes with frame sawing and drilling because they operate at about a tenth of the sawing velocity. The ‘stress epicentre’ is at the location of the crushed, compacted material under the indenter. Changes in the position of the stress epicentre can increase energy efficiency by as much as 100% and reduce the generation of vertical force by as much as 70%. Drilling tests using feed/revolution as the measure of penetration are used to simulate the variable velocity of frame saws by reducing the revolutions/minute. These tests reveal a previously unrecorded sawing mechanism that can improve the use of frame saws because strong granite can now be frame sawn with diamond. This improved potential should also apply to drill bits if they use feed per revolution as the means of penetration, instead of a static bit load. By measuring diamond by volume rather than by weight, and considering alternative options, accurate tool control can now be achieved, with every aspect being predictable. Optimisation of rock sawing operations has shown that performance can be increased by 100–200% with tools removing as much as 30 tonnes in saw cuts per carat of diamond consumed. Because some rock mechanics terms used in the paper may have different meanings in the rock sawing context, a glossary of terms with further explanations is included at the end of the paper.     

Multifactorial fuzzy approach to the sawability classification of building stones

The performances of circular sawing with diamond impregnated tools were evaluated in stone processing plants located in some areas of Turkey. Samples were collected from these factories for the laboratory tests. Uniaxial compressive strength, tensile strength, Schmidt hammer value, point load strength, impact strength, Los Angeles abrasion loss and P-wave velocity were determined in the laboratory. Performance measurements and stone properties were evaluated by using the multifactorial fuzzy approach which is a special case of multiple objective multifactorial decision making for the sawability classification of building stones. Using three different decision functions, the sawing performances of diamond saws were classified into three categories: excellent, good and poor. It is possible to evaluate the sawability and select a suitable diamond saw for a new building stone by only some stone properties testing using the developed fuzzy classification system.     

金刚石绳锯模拟切割反应堆重混凝土试验研究

金刚石绳锯是目前国外石材开采和锯切的新技术。采用金刚石串珠绳锯对两种组分不同的重混凝土进行了模拟切割试验。根据试验结果表明:在反应堆退役过程中,推荐采用金刚石串珠绳锯对密度较小,内含金属较少的重混凝土实施拆除解体。     

锯切花岗岩用金刚石有序排列锯片的研制

本文叙述了金刚石均匀分布／有序排列的优越性,引用信息产业集成电路的先进制造技术与工艺研制成锯切花岗岩用金刚石有序排列锯片。对比实验表明,在相同胎体配方与工艺条件下,有序排列锯片的锯切效率比常规锯片提高20％-30％,锯切速度高达7m／min以上。在我国金刚石工具行业中采用与推广金刚石有序排列锯片将具有重大意义。     

金刚石圆锯片切割石材及有限元分析

通过XK5032C型数控铣床进行切削花岗石试验研究,主要考察了加工参数对圆锯片切削力的影响,确定了金刚石圆锯片切削花岗石时加工参数对切削力的影响规律。切削力的大小随着切削深度和进给速度的增加而增大,而随着主轴转速的增大而减小。通过ANSYS软件进行了有限元分析,研究在不同的加工参数下,金刚石圆锯片实际受力情况,分析其中的变化规律。     

金刚石均匀分布并有序排列是改善金刚石工具性能的有效途径

本文介绍了近年来金刚石均匀分布/有序排列在国内外金刚石工具中的应用与效果,解决了金刚石工具效率与寿命相互矛盾的难题,通过优化与控制工具内部金刚石之间的间距,实现了既提高工具寿命,又增加效率的目的。讨论了金刚石均匀分布/有序排列的功能以及各参数的关系。简要地介绍了实施金刚石均匀分布/有序排列的工艺措施。     

Diamond wire sawing in ornamental basalt quarries: technical,economic and environmental considerations

The market interest in ornamental rocks commercially referred to as “stones” has grown significantly in recent years, particularly regarding basalt. This has resulted in the widespread use of diamond wire equipped with sintered diamond beads for precision sawing in basalt quarries, especially those located in the industrialized countries; it also has the advantage of preventing rock damages. Diamond wire has been widely used in up-line cutting and other sawing works in both marble and granite quarries for decades; therefore, performance data about the use of this tool on these two different types of rocks are widely documented in academic literature. However, for basalt sawing, information pertaining to the use of diamond wire is unavailable due to various reasons, but mostly because of to its relatively recent introduction in the basalt quarries and also to the historical low market demand for processed basalt in the past. This study offers a possible solution to this lack of information and provides a technical, economic and environmental assessment of diamond wire used in quarrying basalt for ornamental purposes. After an overview on the state of the art of diamond wire and on the final use of processed basalt, the study describes the experimental plan and the results. These show a tool yield much higher than those measured when diamond wire is used on other silicate dimension stones (e.g. granites). Moreover, the composition of basalt sawdust (sludge) has been analysed in the laboratory and has indicated the absence of polluting materials related to tool wear; therefore, basalt sludge, which is made of water and micronized basalt, can be used as a secondary raw material for the environmental restoration of the area or for any other purpose. Further research on other lithotypes is also proposed.

     

孕镶齿切削效率数值模拟及实验研究孕镶齿切削效率数值模拟及实验研究

PDC钻头和牙轮钻头在深部难钻地层中钻进时出现钻头钻进效率低、磨损速度快、寿命短等现象,相对而言,孕镶金刚石钻头凭借其特殊的破岩机理和“自锐性”在此类地层中具有良好的钻进性能,已成为提高深部难钻地层破岩效率的重要手段之一。本文以金刚石浓度、粒度、钻压、转速与孕镶齿的切削效率内在影响规律研究为目的,利用离散元软件PFC3D建立孕镶齿磨削砂岩的物理模型来进行数值模拟,然后进行孕镶齿磨削实验,实验数据与模拟结果的对比,验证了孕镶齿选取平行黏结模型来进行模型建立及仿真的正确性,从而粒度、钻压、转速、浓度对切削效率的影响逐渐降低,同时为孕镶钻头工作性能分析、个性化设计、地层适应性评价及钻头选型提供了依据。     

金刚石框架锯局部结构设计的研究

通过对国内石材荒料切割用金刚石框架锯的结构设计及应用现状的调查，指出主切削运动冲击是造成大部分国产设备加工效率低、稳定性差的关键问题之一，提出了一种简单实用的缓和主运动冲击的结构改进方案。