{"id":1457,"date":"2025-11-15T16:03:00","date_gmt":"2025-11-15T16:03:00","guid":{"rendered":"https:\/\/foredencnc.com\/?p=1457"},"modified":"2025-11-20T14:44:18","modified_gmt":"2025-11-20T14:44:18","slug":"spring-folder-type-bireflection-target%ec%8a%a4%ed%94%84%eb%a7%81-%ed%8f%b4%eb%8d%94%ed%98%95-%eb%82%b4%ea%b3%b5%eb%b3%80%ec%9c%84%ed%83%80%ea%b2%9f","status":"publish","type":"post","link":"https:\/\/foredencnc.com\/?p=1457","title":{"rendered":"Spring Folder Type Bireflection Target(\uc2a4\ud504\ub9c1 \ud3f4\ub354\ud615 \ub0b4\uacf5\ubcc0\uc704\ud0c0\uac9f)"},"content":{"rendered":"\n<h3 class=\"wp-block-heading\">Description<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>The most important item in the &#8220;A&#8221; measurement out of the tunnel measurement is the convergence measurement.<br>The purpose of the crown and the convergence measurement is to verify the stability of the ground surrounding the tunnel and the data is important to verify its conditions due to the tunnel excavation, and for predicting the ultimate displacement and determining whether or not the lining should be added. However, despite the fact that engineers reside in the field of tunnels and install various instruments for measurement, tunnel collapsing accident is still going on due to different reasons.<br>In order to verify the effect of the primary strut and tunnel stability in tunnel excavation, it is necessary to install measuring instruments for measurement as soon as possible in the vicinity of the tunnel blind end, but the initial displacement is often lost due to missing of the installation timing because of laying the shortcrete. <\/li>\n\n\n\n<li>Normally, it is not easy to determine the stability entirely because of the lack of the data on and on when the measurement instrument is damaged by scattered debris in case of working combined with excavation by machine and blasting at the same time.<\/li>\n<\/ul>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter size-full is-resized\"><img loading=\"lazy\" decoding=\"async\" width=\"303\" height=\"197\" src=\"https:\/\/foredencnc.com\/wp-content\/uploads\/2025\/11\/image-39.png\" alt=\"\" class=\"wp-image-1459\" style=\"width:475px;height:auto\" srcset=\"https:\/\/foredencnc.com\/wp-content\/uploads\/2025\/11\/image-39.png 303w, https:\/\/foredencnc.com\/wp-content\/uploads\/2025\/11\/image-39-300x195.png 300w\" sizes=\"auto, (max-width: 303px) 100vw, 303px\" \/><\/figure>\n<\/div>\n\n\n<h3 class=\"wp-block-heading\">Composition &amp; Characteristic<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>In the field of tunnels, the conventional fixed type crown and the bi-reflection target can not resist the scattered debris made during the blasting work and the loss ratio of the target reaches about 20~30%.<\/li>\n\n\n\n<li>Moreover, using the conventional way delays the installation timing to reduce the loss ratio or it often measures by separating the target and then mounting again one by one according to the blasting work time. On the contrary, the spring-fold type bi-reflection target adopted a simple method that it becomes recovered to the original position by a fixing device and the spring connected with prism in case when it is hit by scattered debris when blasting.<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">Specification<\/h3>\n\n\n\n<!DOCTYPE html>\n<html lang=\"vi\">\n<head>\n    <meta charset=\"UTF-8\">\n    <meta name=\"viewport\" content=\"width=device-width, initial-scale=1.0\">\n    <title><\/title>\n    <style>\n        body {\n            font-family: Arial, sans-serif;\n            padding: 20px;\n            background-color: #f5f5f5;\n        }\n        .container {\n            max-width: 900px;\n            margin: 0 auto;\n            background-color: white;\n            padding: 20px;\n            border-radius: 8px;\n            box-shadow: 0 2px 4px rgba(0,0,0,0.1);\n        }\n        h1 {\n            color: #333;\n            text-align: center;\n            border-bottom: 3px solid #4CAF50;\n            padding-bottom: 10px;\n        }\n        table {\n            width: 100%;\n            border-collapse: collapse;\n            margin-top: 20px;\n        }\n        th, td {\n            border: 1px solid #ddd;\n            padding: 12px;\n            text-align: left;\n        }\n        th {\n            background-color: #4CAF50;\n            color: white;\n            font-weight: bold;\n        }\n        tr:nth-child(even) {\n            background-color: #f9f9f9;\n        }\n        tr:hover {\n            background-color: #f0f0f0;\n        }\n    <\/style>\n<\/head>\n<body>\n    <div class=\"container\">\n        <h1><\/h1>\n        \n        <table>\n           \n            <tr>\n                <td><strong>Model Name<\/strong><\/td>\n                <td>SJ-1402 (Patent No. 10-0951811)<\/td>\n            <\/tr>\n            <tr>\n                <td><strong>Target material<\/strong><\/td>\n                <td>Reflection sheet: Polyvinyl chloride. Body: Steel<\/td>\n            <\/tr>\n            <tr>\n                <td><strong>Target Dimension<\/strong><\/td>\n                <td>Reflection plate (45 X 50mm), Fixing plate (50 X 60mm) &#038; Thickness 4mm<\/td>\n            <\/tr>\n            <tr>\n                <td><strong>Target rotation angle<\/strong><\/td>\n                <td>110\u00b0 (1 way), Recovered to original position<\/td>\n            <\/tr>\n            <tr>\n                <td><strong>Spring Pin material<\/strong><\/td>\n                <td>Special steel<\/td>\n            <\/tr>\n            <tr>\n                <td><strong>Spring Pin dimension<\/strong><\/td>\n                <td>Spring Cavity Pin(400X25mm), Target coupling (50X25mm)<br>\n                    Anchor Bolt(45X10mm), Total length for coupling: Approx. 470mm<\/td>\n            <\/tr>\n            <tr>\n                <td><strong>Spring Pin rotation angle<\/strong><\/td>\n                <td>180\u00b0 (Front\/Rear, Left\/Right), Recovered to original position<\/td>\n            <\/tr>\n        <\/table>\n    <\/div>\n<\/body>\n<\/html>\n\n\n\n<details class=\"wp-block-details is-layout-flow wp-block-details-is-layout-flow\"><summary>This is subject to change without prior notice in order to improve the product\u2019s quality.<\/summary>\n<p class=\"wp-block-paragraph\"><\/p>\n<\/details>\n\n\n\n<h3 class=\"wp-block-heading\">Reference<\/h3>\n\n\n\n<!DOCTYPE html>\n<html lang=\"vi\">\n<head>\n    <meta charset=\"UTF-8\">\n    <meta name=\"viewport\" content=\"width=device-width, initial-scale=1.0\">\n \n    <style>\n        body {\n            font-family: Arial, sans-serif;\n            padding: 20px;\n            background-color: #f5f5f5;\n        }\n        .container {\n            max-width: 1200px;\n            margin: 0 auto;\n            background-color: white;\n            padding: 20px;\n            border-radius: 8px;\n            box-shadow: 0 2px 4px rgba(0,0,0,0.1);\n        }\n        h1 {\n            color: #333;\n            text-align: center;\n            border-bottom: 3px solid #2196F3;\n            padding-bottom: 10px;\n        }\n        table {\n            width: 100%;\n            border-collapse: collapse;\n            margin-top: 20px;\n        }\n        th, td {\n            border: 1px solid #ddd;\n            padding: 12px;\n            text-align: left;\n            vertical-align: top;\n        }\n        th {\n            background-color: #2196F3;\n            color: white;\n            font-weight: bold;\n        }\n        .header-col {\n            background-color: #64B5F6;\n            color: white;\n            font-weight: bold;\n        }\n        tr:hover td {\n            background-color: #f0f0f0;\n        }\n        ul {\n            margin: 5px 0;\n            padding-left: 20px;\n        }\n        li {\n            margin: 3px 0;\n        }\n    <\/style>\n<\/head>\n<body>\n    <div class=\"container\">\n      \n        \n        <table>\n            <thead>\n                <tr>\n                    <th>Type<\/th>\n                    <th>Tape Extensometer<\/th>\n                    <th>Fixed type Convergence Meter<\/th>\n                    <th>Spring folder type Convergence Meter<\/th>\n                <\/tr>\n            <\/thead>\n            <tbody>\n                <tr>\n                    <td class=\"header-col\">Measurement \/ Installation timing<\/td>\n                    <td>\n                        <ul>\n                            <li>Hang a ring on the convergence pin to maintain the tape tensile force for measurement using dial gauge<\/li>\n                            <li>Installation: After laying 1st and 2nd S\/C<\/li>\n                        <\/ul>\n                    <\/td>\n                    <td>\n                        <ul>\n                            <li>Prism target is installed on the convergence pin and then measure using electro-optical wave measuring instrument.<\/li>\n                            <li>Installation: After laying 1st and 2nd S\/C<\/li>\n                        <\/ul>\n                    <\/td>\n                    <td>\n                        <ul>\n                            <li>Same as left<\/li>\n                            <li>Installation: Immediately after drilling the blind end.<\/li>\n                            <li>Possible to find position displacement<\/li>\n                        <\/ul>\n                    <\/td>\n                <\/tr>\n                <tr>\n                    <td class=\"header-col\">Advantage<\/td>\n                    <td>\n                        <ul>\n                            <li>Good precision: 0.01mm<\/li>\n                        <\/ul>\n                    <\/td>\n                    <td>\n                        <ul>\n                            <li>Possible to find position displacement<\/li>\n                            <li>Possible for 3-D analysis<\/li>\n                        <\/ul>\n                    <\/td>\n                    <td>\n                        <ul>\n                            <li>Possible to find position displacement<\/li>\n                            <li>Possible for 3-D analysis<\/li>\n                            <li>Minimum loss rate for blasting<\/li>\n                            <li>Minimum loss of displacement in the beginning of drilling<\/li>\n                        <\/ul>\n                    <\/td>\n                <\/tr>\n                <tr>\n                    <td class=\"header-col\">Disadvantage<\/td>\n                    <td>\n                        <ul>\n                            <li>Excessive individual error during measurement time<\/li>\n                        <\/ul>\n                    <\/td>\n                    <td>\n                        <ul>\n                            <li>Excessive loss rate for blasting<\/li>\n                            <li>Lack of data continuity due to the loss<\/li>\n                        <\/ul>\n                    <\/td>\n                    <td>&#8211;<\/td>\n                <\/tr>\n                <tr>\n                    <td class=\"header-col\">Economic condition<\/td>\n                    <td>No efficiency<\/td>\n                    <td>Excessive cost for re-installation<\/td>\n                    <td>Good economic condition<\/td>\n                <\/tr>\n            <\/tbody>\n        <\/table>\n    <\/div>\n<\/body>\n<\/html>\n\n\n\n<p class=\"wp-block-paragraph\"><\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><\/p>\n","protected":false},"excerpt":{"rendered":"<p>Description Composition &amp; Characteristic Specification Model Name SJ-1402 (Patent No. 10-0951811) Target material Reflection sheet: Polyvinyl chloride. Body: Steel Target Dimension Reflection plate (45 X 50mm), Fixing plate (50 X 60mm) &#038; Thickness 4mm Target rotation angle 110\u00b0 (1 way), Recovered to original position Spring Pin material Special steel Spring<span class=\"more-link\"><a href=\"https:\/\/foredencnc.com\/?p=1457\">Read More &rarr;<\/a><\/span><\/p>\n","protected":false},"author":2,"featured_media":1459,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[135,3],"tags":[110,111],"class_list":["entry","author-editor","post-1457","post","type-post","status-publish","format-standard","has-post-thumbnail","category-etc-products","category-products","tag-spring-folder-type-bireflection-target","tag-111"],"_links":{"self":[{"href":"https:\/\/foredencnc.com\/index.php?rest_route=\/wp\/v2\/posts\/1457","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/foredencnc.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/foredencnc.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/foredencnc.com\/index.php?rest_route=\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/foredencnc.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=1457"}],"version-history":[{"count":1,"href":"https:\/\/foredencnc.com\/index.php?rest_route=\/wp\/v2\/posts\/1457\/revisions"}],"predecessor-version":[{"id":1460,"href":"https:\/\/foredencnc.com\/index.php?rest_route=\/wp\/v2\/posts\/1457\/revisions\/1460"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/foredencnc.com\/index.php?rest_route=\/wp\/v2\/media\/1459"}],"wp:attachment":[{"href":"https:\/\/foredencnc.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=1457"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/foredencnc.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=1457"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/foredencnc.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=1457"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}