Treesearch

Lumber volume recovery in sawmilling is determined by a confusing interaction of several factors. The more one knows about each individual factor, the more one can understand how the factors interact. The author identifies and discusses in detail seven factors influencing lumber recovery. Past and current research is cited, and examples are given to illustrate the points made.

Unbleached kraft paperboard is produced from wood fiber in an industrial papermaking process. A highly specific and detailed model of the process is presented. The model is also presented as a working computer program. A user of the computer program will provide data on physical parameters of the process and on prices of material inputs and outputs. The program is then used to calculate material and energy requirements of the process, and to calculate related revenues and variable costs. The program does not derive capital costs or fixed costs. The program is most useful in estimating...

This publication presents 124 charts on past trends in the production, consumption, and foreign trade of forest products in the United States. The charts have been printed full-page width for use (with opaque projectors of in making overhead transparancies) as visual aids by teachers, state and federal resource managers, industry personnel, or anyone else interested in communicating this information.

“With more stringent requirements on discharge water quality and with escalating water treatment costs, water recycling within the paper mill is of growing importance. A serious problem resulting from more white-water recycling is reduced drainage and fiber or fines retention because of diminished polymeric additive performance. To provide better insight for overcoming polymeric additive performance problems, this work investigated interactions between pulp furnish and dissolved and/or suspended materials accumulating in whitewater systems. Effects of differing levels of materials carried...

A theory of thin plates which is physically as well as kinematically nonlinear is, developed and used to characterize elastic material behavior for arbitrary stretching and bending deformations. It is developed from a few clearly defined assumptions and uses a unique treatment of strain energy. An effective strain concept is introduced to simplify the theory to a special theory having fewer parameters and being capable of characterizing paper. A procedure is given for matching the special theory to edgewise compressive data of paperboard.

The design of large flat-roof systems necessitates a means of analyzing the required strength of bracing members. If the braced beam is initiallyperfectly straight, it will remain straight until it buckles; the prebuckling stresses in the braces are theoretically zero. If the braced beam has initial imperfections,they will grow under load and so will the stresses in the braces. Thus, there is need to analyze the buckling of beams with initial imperfections. This was done in the context of linear small-deflection theory; the results are simple and suitable for use in design where loads are...

COMPARE is a FORTRAN computer program resulting from a study to develop methods for comparative economic analysis of alternatives in industrial wood and bark energy systems. COMPARE provides complete guidelines for economic analysis of wood and bark energy systems. As such, COMPARE can be useful to those who have only basic familiarity with investment analysis of wood and bark energy systems. This report provides instructions on how to prepare data for COMPARE, information on how to use the program, sample data, sample output, and a listing of the program. COMPARE ranks investment alternati...

This paper compares results of all wall tests with analytical predictions of performance.Conventional wood-stud walls of one configuration failed at bending loads that were 4 to 6 times design load.The computer model overpredicted wall strength by and average of 10 percent and deflection by an average of 6 percent.

The DEP computer program is a modified discounted cash flow computer program designed for analysis of problems involving economic analysis of wood drying processes. Wood drying processes are different from other processes because of the large amounts of working capital required to finance inventories, and because of relatively large shares of costs charged to inventory insurance and tax. DEP’s flexibility allows calculation of rate of return, break-even transfer prices, or break-even facilities costs. Data input requirements are simplified into basic analytical components that are explained...

Methods other than presented here should be used to assess projects for likely return on investment; but, payback is simple to calculate and can be used for calculations that will indicate the relative attractiveness of alternative improvement projects. This paper illustrates how payback ratios are calculated, how they can be used to rank alternative improvement projects, and how to calculate the benefit value of improvement projects.