![]() ![]() Timber rails wore rapidly: later, flat cast-iron plates were provided to limit the wear. Initially the wagons were guided by human muscle power subsequently by various mechanical methods. The earliest form of railway was a wooden wagonway, along which single wagons were manhandled, almost always in or from a mine or quarry. See also: Permanent way (history), Wagonway, and Plateway Deriving from the name of the bar, the distance between these rails is also referred to as the track gauge. The term derives from the "gauge", a metal bar with a precisely positioned lug at each end that track crews use to ensure the actual distance between the rails lies within tolerances of a prescribed standard: on curves, for example, the spacing is wider than normal. The most common use of the term "track gauge" refers to the transverse distance between the inside surfaces of the two load-bearing rails of a railway track, usually measured at 12.7 millimetres (0.50 inches) to 15.9 millimetres (0.63 inches) below the top of the rail head in order to clear worn corners and allow for rail heads having sloping sides. A structure gauge specifies the outline into which structures (bridges, platforms, lineside equipment etc.) must not encroach. A loading gauge is a two-dimensional profile that encompasses a cross-section of the track, a rail vehicle and a maximum-sized load: all rail vehicles and their loads must be contained in the corresponding envelope. Railways also deploy two other gauges to ensure compliance with a required standard. The term derives from the metal bar, or gauge, that is used to ensure the distance between the rails is correct. Since many different track gauges exist worldwide, gauge differences often present a barrier to wider operation on railway networks. All vehicles on a rail network must have wheelsets that are compatible with the track gauge. Need help with design, printing or mailing? Ask for a consultation.In rail transport, track gauge is the distance between the two rails of a railway track. Envelopes marked with asterisk (*) are too small to mail.Īlso called A-style, this contemporary square flap design is idea for photographs, greeting cards, small booklets, and promotional pieces. ![]() Square envelopes are nonstandard and require additional postage to mail.ĭeep pointed flap traditionally used for formal announcements and invitations. Square EnvelopesThis unusual shape attracts attention to contents. These envelopes can not be processed through inserting equipment or run through a laser printer. The open side allows for automatic insertion.Ĭenter seam makes this style more durable for mailing heavy-weight materials. This style is ideal for annual reports, brochures, sales materials, and more. Square flaps are contemporary, but not recommended for machine insertion. Wallet flaps provide a large area ideal for imprinting (used on remittance envelopes). Commercial and Side Seam flap styles are ideal for machine insertion. Widely used for business and personal correspondence. Pocket folder with bound in multi-page documentĬommercial Envelopes Business and Correspondence Envelopes Outside diameter: 116 mm, Hole area: 20 mm Postcard, largest to mail USPS Postcard rate Postcard, smallest to mail USPS Postcard rate
0 Comments
Leave a Reply. |