Có cao thủ giao thông giúp với:
hydroplaning
aquaplaning
hai từ trên chắc chắn đồng nghĩa trong tiếng Anh, thế tiếng Việt mình gọi là gì ạ?
thuật ngữ giao thông
Có cao thủ giao thông giúp với:
hydroplaning
aquaplaning
hai từ trên chắc chắn đồng nghĩa trong tiếng Anh, thế tiếng Việt mình gọi là gì ạ?
hydroplaning và aquaplaning là hiện tượng lốp xe trượt trên mặt nước, thấy thường được dịch là "hiện tượng chêm nước". Mình cũng k hiểu chêm ở đây nghĩa là gìOriginally Posted by Tanyenbai
excellent! Thank you Mr. Hai
TIMBER INCREMENT BORER
[IMG]www.flickr.com/photos/esagor/2673805487/[/IMG]
không biết công nhân mình gọi thứ đó là gì? kỹ sư gọi là gì? dùng dụng cụ này để kiểm tra cái gì? Giúp với các bạn nào đã từng trông thấy?
Bác TYB, Ltdra tim được bài viết bên dưới nhưng xem chừng không thỏa mãn được câu hỏi của bác cho cái tên gọi trong nghề ờ VN.
Increment Borers
The increment borer is essential for extracting a core of wood from trees, logs, poles or
timbers. The core extracted is used for many purposes including determination of growth
rate, age, tree soundness, penetration of chemicals in the wood treating business, and
specific gravity studies of wood. An increment borer consists of three parts. They are a
handle, a borer bit and an extractor. When not in use, the borer bit and extractor fit inside
the handle and form a compact unit. Most increment borers have Teflon coated bits.
This coating helps reduce friction, protects against rust and keeps the bit cleaner and
extends the life of the bit.
Making the Right Selection
There are three things to consider when you choose an increment borer. They are length,
diameter and style.
Borer bit length depends on the size of the trees you will be boring. Length is measured
from the tip of the threads to the end of the round section of the borer bit. This is the
maximum depth the bit will penetrate.
Core diameter of the wood sample is determined by the inside diameter of the opening at
the threaded end of the bit. For general forestry use, 0.169" is commonly used, 0.200" is
used for wood preserving testing, and 0.500" is used for large amounts of wood for
quantitative analysis.
Two or 3-thread style is a matter of personal preference. A 2-thread borer has two
threads on the cutting edge of the bit, each originating 180° apart. A 3-thread borer has
three threads, each originating 120° apart. The 3-thread borer will engage the wood
faster and easier than the 2-thread borer. A 3-thread borer will also turn easier inside the2
tree. For each 360° turn of the handle, a 2-thread borer will penetrate deeper and come
out of the tree faster than a 3-thread borer.
To take an increment core, follow these simple steps:
1. Remove the borer bit and extractor from inside the handle. Place the extractor in a
pocket of your cruiser vest for convenience and protection of the extractor.
2. Assemble the handle and borer bit by:
a. pushing the locking latch away from the handle with your thumb,
b. inserting the square end of the borer bit inside the handle, and then
c. returning the locking latch completely around the borer bit "collar".
You are now ready to begin boring. However, we suggest you apply beeswax to the
threads and shank before you begin boring.
3. Align the borer bit and the handle so that the bit will penetrate through or towards the
center of the tree at right angles to the tree. In any other alignment, the annual growth
rings seen in the extracted core will be distorted and could result in erroneous growth
rate analysis.
4. Place the borer bit threads against the tree, preferably in a bark fissure where the bark
is the thinnest. Hold the threads in place with one hand. With your other hand push
forward on the handle and simultaneously turn it clockwise until the bit threads
penetrate the wood enough to hold the bit firmly in place.
5. Then place both hands, palms open, on the ends of the handle and turn the handle
clockwise until the bit reaches the desired depth.3
6. With the bit at the desired depth insert the full length of the extractor, concave side
up. The turn the handle one-half turn counterclockwise to break the core from the
tree and also to turn the extractor concave side down.
7. Pull the extractor from the borer bit. The core will be resting in a channel and held in
place by the small "teeth" at the tip of the extractor. Before examining the core
sample, promptly remove the borer bit from the tree. Clean it and place it and the
extractor back in the handle.
Care and Maintenance of Increment Borers
Here are a few suggestions that will be helpful in maintaining the efficiency and
extending the life of increment borers.
Lubricate with beeswax
A block of beeswax is provided with every increment borer. Penetration and removal of
the borer bit will be easier if beeswax is liberally applied to the threads and shank before
each boring.
Clean with WD-40
WD-40 is an excellent cleaner and rust preventative for an increment borer. It will also
prevent sap acid-etching of the borer. Spray it on and inside the extractor at the end of
each working day. Wipe clean.
Be quick!
Obtain your core samples as rapidly as possible. It's best to remove the bit from the tree
even before examining the core sample. This will reduce the possibility of the bit
becoming stuck or locked in the tree.4
Avoid compression-tension wood
Never bore into suspected compression or tension wood. To explain: a tree leaning
towards the North will have compression wood on the North side. If you bore into
compression wood, the bit could be locked into the tree by the force of the "compressed"
wood. If you bore into the South side, you are boring into "tension" wood, where the ring
width may not be representative. We recommend boring on the East or West side, or if
possible, select another tree.
From: Forestry Suppliers, Inc. Jackson, MS 1994.
Thất bại lớn nhất của đời người là tự đại
Đáng thương nhất của đời người là tự ti.
Tự đại + Tự ti = thất bại đáng thương nhất
Cái trong hình chính xác có tên và thương hiệu là "JIM-GEM® 6" 3 Thread .200 Increment Borers", lên google search là ra nhé
http://en.wikipedia.org/wiki/Increment_borer
Hình như nó là một loại dụng cụ đục lấy mẫu thực vật. Thuật ngữ việt thì k rõ.
Last edited by Bùi Hoàng Hải; 08-04-2012 at 09:39 AM.
LtDra ! chân thành cám ơn bác rất nhiều. Thực ra bài của bác gửi cho đã trả lời một phần câu hỏi rồi. Ví dụ, có nó trong tay là mình dùng được, chí ít thì cũng biết công năng. Vấn đề ở đây là đặt tên tiếng Việt cho công cụ nhập vào Vn. Hiện tượng chêm nước mà anh Hải cho hay, cũng là 1 ví dụ hay về phát triển của lý thuyết giao thông. Có người trước đặt tên, ta phải theo thôi. Nếu không ta mới có quyền đặt tên. Đành phải chờ và đi hỏi thêm vậy.
Chúc mọi điều tốt lành
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