PFC - Saw mills

Reduce your electricity costs

Automatic capacitor banks have been used for many years to compensate reactive power in networks with fluctuating loads. APS provide a comprehensive range of automatic capacitor banks manufactured by leading manufacturers

Costs are kept to a minimum via a series of standard designs. APS unique offering ranges from low-cost standard systems to harmonic resilient systems with de-tuning reactors to high-speed thyristor driven systems for applications such as lifts and saw-mills.

The APS FR P&P Series capacitor banks with detuned filters have been designed for power compensation purposes in networks with fluctuating load levels, a high content of harmonics and where there is a risk of resonance. Power variations are relatively slow (in seconds) so that the switching operations are carried out with contactors.

 

The APS-EMK series capacitor banks have been designed for power factor correction in networks with high fluctuating loads. The power variations are relatively quick (measured in milliseconds) and the operation is thus carried out by thyristors, which are connected to a voltage controller board, so that the connection and disconnection of the capacitor is carried out with zero voltage difference. Transients are prevented between the connection and disconnection of the steps, obtaining an immediate response to the load fluctuations.

 

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Lumber and sawmill equipment is used in sawmill, timber, and forestry applications. Sawmill equipment includes tools and machines to transport, position, cut, and otherwise aid in converting logs into lumber or other processed wood.

Sawmill Process

Sawmills are facilities that process logs into lumber. While modern mills are mostly automated, the fundamental sawmill process has changed little over the past several hundred years. Lumber mill operations are typically grouped into the steps listed below, although they may not occur in the identical order.

1. Trees are felled and trunks are bucked into manageable lengths at the harvest site.
2. A logging truck, train, or log drive transports logs to the sawmill facility.
3. Logs are scaled before entering the mill, either in transport or just outside the facility. This involves measuring, inspecting for defects, and identifying the tree species for the purpose of tracking the volume of salable wood.
4. A system of conveyors, cranes, and other material handling equipment moves the log into the mill. A debarker then strips the bark.
5. The logs may then be decked, or sorted by parameters such as species, size, or intended end use.
6. A band saw cuts small sections from the edges of the log's profile, as shown in the video below.
7. A head saw (also known as a gang saw) breaks the log into cants and flitches. Cants are unfinished logs that require further processing, while flitches are unfinished planks.
8. Cants are then broken down into multiple flitches using a resaw, a type of large band saw.
9. An edger trims irregular edges to produce squared lumber. The flitch ends are trimmed to standard lumber lengths.
10. A kiln or air-drying process removes naturally occurring moisture from the planks. A planer smooths the lumber surface to a uniform width and thickness. The lumber is then inspected, tagged, and shipped to market.

Sawmill Types

Sawmills may be classified by the type of wood they convert or the end product they produce.

Softwood mills convert softwood into lumber and other finished products. Softwood refers to timber from gymnosperm trees and does not necessarily denote a "softer" material. Cedar, pine, redwood, and fir are common softwood trees. Softwoods are commonly used in furniture and outdoor building materials.

Hardwood mills process ash, oak, maple, birch, and other angiosperm trees. Hardwood is preferred for woodworking, is often used in furniture-making, and is more expensive than softwood. Some hardwoods, such as mahogany and cherry, are prized for their attractive aesthetic qualities.

Stud mills are specialized mills that produce studs, which are vertical support members found in most building walls.

Pulp mills produce fiberboard by using specialized processes and equipment. Fiberboard is used in furniture-making or shipped to paper mills for further processing. Pulp mills debark pulpwood logs and grind them into small chips. The chips are rendered into a porridge-like pulp through steam treatment or digestion using chemical processes. Dried pulp is then cut, stacked, and shipped as fiberboard.

Equipment Types

Sawmills combine disparate equipment types to move logs to and from the mill, prepare them for processing, make cuts, and dispose of waste. The table below lists some common equipment categories and types.

Log Handling and Preparation

https://researchrepository.wvu.edu/cgi/viewcontent.cgi?article=1614&context=etd