tighten fastener hand snug tight sec.sys.

[rekmax]

Решетки для ходьбы на химическом производстве

Tie down clips in place and tight against support?
Recommended tightness of clip:
Using a T-handle or wrench type tool, *tighten fastener hand snug tight*, ensuring that the grating near the fastener is in contact with the support below.
The clip should be tight enough to prevent sliding of the grating.
Every piece of grating restrained at each corner by hold-down clips?
Every piece of grating should be restrained by at least two hold-down clips at each intermediate support.
No grating clip is used to hold two adjacent panels together.

[Jerk]

http://www.multitran.ru/c/m/t=6395842_1_2&s1=snug-tight

[00002]

Snug‐tight is the tightness attained with a few hits of an impact wrench or the full effort of an ironworker using an ordinary spud wrench to bring the connected plies into firm contact. (RCSC)

• Installation beyond snug‐tight is called pretensioning
• Turn‐of‐nut pretensioning involves several steps:
1. The bolt is snug‐tightened
2. Matchmarks are placed on each nut, bolt, and steel surface in a straight line
3. The part not turned by the wrench is prevented from turning
4. The bolt is tightened with a prescribed rotation past the snug‐tight condition
• The specified rotation varies by diameter and length (between 1/3 and 1 turn)
(RCSC, AISC)

В каком-то смысле snug tight и pretensioning перекликается с finger tight и TPFT (turns past finger tight), про которое было недавно в другой ветке. Только тут не затянуть "до упора от руки" (а потом довернуть ключом на определенный угол), а затянуть до упора обычным ключом (а потом довернуть на определенный угол "более конкретным инструментом":).