To: Kendy regarding to UL plastic IMP 和STR

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小型摆管淋雨试验机

IPX5X6X7喷水试验机

1000L恒温恒湿箱

各种试验指现货

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水平垂直燃烧机

自动卷线器试验机

耐划痕试验机

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灼热丝试验机现货

GB1002插头量规

IPX1-X7淋雨现货

IEC61347/UL935镇流器热试验箱

灯具防风罩

IK冲击试验机

UL498插头插座量规

VDE0620插头插座量规

稳定性试验台

家电温升测试角

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IEC60335试验指甲

Kendy(313208377) 14:43:34
XDJM，UL网站上查到的塑料件UL证书上：RTI  下面有两栏：ELEC（电器）和MECH（机械）； MECH（机械）下面又有两栏：IMP 和STR 。IMP 和STR 是不是分别代表结构件和冲击件，两者有什么区别？
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4 `, E/ L" l( W/ wThermal-Aging Program
/ z: ~+ \* M2 yThe materials covered by this program have, in many cases, been investigated with respect to retention of certain critical properties (e.g. dielectric, tensile, impact, and the like) as part of a longtime thermal-aging program conducted in accordance with Underwriters Laboratories Inc. Standard for Polymeric Materials-Long Term Property Evaluations, UL 746B.

" ]- {( L5 i: S4 i' E7 bThe end-of-life of a material at each test temperature in this program has been assumed to be the time when the value of the critical property had decreased to 50 percent of its original (as received) value. If a material has been investigated under the thermal-aging program, the Relative Temperature Index (RTI), in degrees C shown is based on a comparison with a material which has acceptable service experience and correlates numerically with the temperatures above which the material is likely to degrade prematurely.
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" d  P) L. o2 t% D- m4 }3 {If a material has not been investigated under the thermal-aging program, the temperature index shown is based on the generic class of the material. A tabulation of the temperature indices according to generic material class is included in UL 746B and is based on past field-test performance and chemical structure.
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% ?' G; N* ^; eMore than one RTI may be appropriate for a given material depending on the property requirements for a given application. In certain cases, higher temperatures are permitted if so specified by the end-use product standard.

! q( i+ U3 ?( [% `+ b: C! H! Z7 aRelative Temperature Index (RTI)
Maximum service temperature for a material, where a class of critical property will not be unacceptably compromised through chemical thermal degradation, over the reasonable life of an electrical product, relative to a reference material having a confirmed, acceptable corresponding performance defined RTI.
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5 y  i9 o: K1 u5 k$ Y0 w3 DRTI Elec
: y  m& P$ U' U& L- Q4 ?) fElectrical RTI, associated with critical electrical insulating properties.

7 A) g  G- \$ e; LRTI Mech Imp
3 L; c3 p1 u. Z' j' V) qMechanical Impact RTI, associated with critical impact resistance, resilience and flexibility properties.
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. ?, A* B  }4 D9 `1 ^RTI Mech Str
Mechanical Strength (Mechanical without Impact) RTI, associated with critical mechanical strength where impact resistance, resilience and flexibility are not essential.
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( z6 Y. w" Q# N0 S0 f5 ^http://www.ul.com/plastics/thermal.html