GB 4820-2013Sawn timber for shaft lifting guides (English PDF)

Foreword

3.4 of this standard are mandatory, the rest are recommended. This standard was drafted in accordance with GB/T 1.1-2009 given rules. This standard replaces GB 4820-1995 "tank Woods", compared with GB 4820-1995 The main changes are as follows:

--- Suitable species expanded from the original six to seven kinds, and filling Latin;

--- For articulated, dead knots, Poles have done a permissible limits tightened restrictions;

--- Increased sampling of the product. Please note that some of the content of this document may involve patents. Release mechanism of the present document does not assume responsibility for the identification of these patents. This standard by the National Standardization Technical Committee timber (SAC/TC41) and focal points. This standard was drafted. Heilongjiang Provincial Academy of Forestry, Coal Datun Coal and Electricity Company, Shandong Yankuang Group was for the center. The main drafters of this standard. Tie force, put off, Li River, Songrun Hui, Wang Wei Qi, Liu Decheng, Heping Sheng, Ding Jianqiang, plum gold, Jiang Lu, Chen, Han Bin, Mu Guanghui, Zhao Nan, Li Weidong. This standard replaces the standards previously issued as follows:

--- GB 4820-1984, GB 4820-1995. Woods tank

1 Scope

China's mandatory standard for shaft guide timber - the sawn baulks fixed down the full depth of a mine shaft that steer the cage and the skip, and that have to hold their dimensions and their strength in a wet shaft for years while a loaded cage runs against them. It specifies the technical requirements, the test methods and the measurement of volume, and it applies to the sawn timber used specifically as shaft guides in mine shafts. Clauses 3 and 4 are mandatory and the remainder is recommended. The requirements cover the species that may be used, the dimensions and the permitted deviations, the moisture content, and the defects that may be present and to what extent - the knots, live and dead, the slope of grain, the checks, shakes and splits, the wane, the decay and the insect damage - with the volume of a piece determined from the sawn timber volume tables of GB/T 449, the sawing quality assessed to GB/T 4822 and the batches sampled and judged to GB/T 17659.2. Compared with the 1995 edition it replaces, the list of admissible species is widened from six to seven and given with the Latin names, the limits on knots, dead knots and slope of grain are tightened, and product sampling is added. Issued on 12 November 2013 and in force since 11 September 2014, it replaces GB 4820-1995 and is held by SAC/TC 41.

This standard specifies the technical requirements for tank woods, test methods and measurement volume. This standard applies to the mine shaft special tank woods.

2 Normative references

The following documents for the application of this document is essential. For dated references, only the dated version suitable for use herein Member. For undated references, the latest edition (including any amendments) applies to this document.

GB/T 449 sawn timber volume table GB/T 4822 Test sawmills

GB/T 17659.2 sawn timber batch inspection Sampling and judging methods - Part 2. Lumber batch inspection Sampling and judging methods

3 Technical requirements

3.1 Species Fir (Abiesspp.), Spruce (Piceaspp.), Armand Pine (Pinusarmandi), pine (Pinuskoraiensis), kwangtungensis (Pinuskwangtungensis), Pinus sylvestris (Pinussylvestrisvarmongolica), Ash (Fraxinusmandshurica).

4 Test methods and volume measurement

4.1 Sampling Method Execution according to the provisions GB/T 17659.2 of.

4.2 size calibration Execution according to the provisions GB/T 4822's.

4.3 Evaluation Material Execution according to the provisions GB/T 4822's.

4.4 Volume measurement Execution according to the provisions GB/T 449's.