プラント計装工事の設計
計装工事設計の技法（手法）を解りやすく解説

一般社団法人

日本計装工業会

本書は、プラント計装工事設計の手法について解説したものです。
近年では、計装工事設計はプラント設計の一環として他部門の設計と連携し、コンピ
ュータを使用して行われることが一般的ですが、本書ではそのような環境下での計装工事設計において、コンピュータを使用しない手設計について詳しく説明しています。
まず、計装工事設計に必要な「装置・機器配置図」や「配管図」などの図面を示し、これらから設計に必要なデータを読み取り、具体的な設計手順や方法、注意点等を解説しています。
さらに、実際の設計プロセスで必要な図面の作成方法やフォーマット、表記方法を示し、具体的な設計結果としての図面を多数、例として掲載しています。 また、計装工
事資材の拾い出し方法についても解説しています。
ただし、本書は大型プラントの一般的な計装工事の設計に関して記載されており、小規模プラントなど、具体的なプロジェクトの要求や内容、現場の要件に応じて適切にカ
スタマイズし、実際の状況に合わせた適切な調整や追加が行われることを推奨します。
最後に、本書が計装工事設計に携わる皆さんにとって有益な情報源となり、最良の結果を得るために積極的に活用していただければ幸いです。

特記
法令、規格、基準等は、本書作成時の最新版を参照しているが、都度見直し・改定が行われるので最新版に読替えることをお願いする。

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第 1 編 計装一般
1. 計装とは····················································

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2. 計装化の目的と役割
3. 計装の範囲·············································

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3.1 プロジェクト全般
3.2 計装業務···········································

2···················································

5

3.2.1 計装システム設計·····································

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3.2.2 計装機器設計·········································

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3.2.3 計装機器調達·········································

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3.2.4 計装工事設計·········································

13·····································

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3.2.5 計装工事資材調達
3.2.6 現地工事·············································

3.2.7 計装工事試験・検査
3.2.8 計器調整・ループテスト·······························

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第 2 編 計装工事設計
1. 共通

14

···············································

3.2.9 試運転
4. 3D CAD 設計

14······························································································

1.1 計装関連法令等

15·············································

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1.1.1 法令等の種類·········································

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1.1.2 計装関連法令等·······································

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1.2 計装工事設計用図書
1.3 他部門との関係·············································

21·········································

32

1.4 計装工事設計仕様書

1.5 設計図書用図記号（日本計装工業会標準図記号）
1.6 作図要領···············

51··················································

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1.6.1 作図に関する初期設定
1.6.2 文字·································

61·················································

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1.6.3 図記号の使い方·······································

1.7 プラント内の特殊環境対策··································

62
62

1.7.1 硫化水素の影響と対策
1.7.2 水素の影響と対策·································

63·····································

63

1.7.3 その他危険流体の影響と対策（アンモニア、塩素、フッ素等）

64

1.7.4 その他···············································

64

2. 計器室内工事···················································

65

2.1 設計手順···················································

65

2.2 設計項目···················································

66·················································

66·······················································

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2.3 設計用図書
2.4 設計·····································

66

2.4.2 計装電源

2.4.1 計器室内機器配置·············································

67

2.4.3 計装接地·············································

70

2.4.4 計器室内配線経路
2.5 設計図書の作成·····································

73·············································

74

2.5.1 計器室内機器配置図···································

2.5.2 計装電源系統図、計装接地系統図
2.5.3 計器室内配線図
2.5.4 計器室内機器架台図
2.5.5 計装配線接続表
3. ケーブルウエイ工事·······················

75
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78···································

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3.1 設計手順···················································

80

3.2 基本計画···················································

3.2.1 計画設計項目

81·········································

81

3.2.2 計画用図書···········································

82

3.2.3 計画設計·············································

82

3.2.4 計画図書の作成
3.3 設計······························································································

3.3.1 設計項目·············································

3.3.2 設計用図書···········································

3.3.3 ケーブルウエイ仕様····································

3.3.4 布設経路（ダクト、ピット等）

83
84
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84

·························

87

3.3.5 計器室内引込み·······································

88

3.3.6 セパレータの構成·····································

92

3.3.7 ダクトサポート方法···································

92

3.3.8 耐火·················································

95

3.3.9 資材·················································

95

3.4 設計図書の作成·············································

97

3.4.1 布設図···············································

97

3.4.2 ケーブルダクト製作図
3.4.3 その他の図書
4. 主ケーブル布設工事································· 100········································· 111············································· 113

4.1 設計手順··················································· 113

4.2 設計項目··················································· 113

4.3 設計用図書
4.4 設計················································· 113······················································· 114

4.4.1 ケーブル仕様
4.4.2 ふ設········································· 114················································· 115

4.4.3 ケーブルウエイのサイズ
4.4.4 資材································ 116················································· 117

4.5 設計図書の作成············································· 122

4.5.1 主ケーブル布設図····································· 122

4.5.2 ケーブル一覧表······································· 124

4.5.3 JB 一覧表············································ 124

5. 現場計装盤・計器据付工事······································· 127

5.1 設計手順··················································· 127

5.2 設計項目··················································· 127

5.3 設計用図書················································· 127

5.4 設計······················································· 128

5.4.1 現場計装盤及びスタンション据付······················· 128

5.4.2 現場計器据付（他部門据付計器）······················· 131

5.4.3 資材················································· 131

5.5 設計図書の作成············································· 131

5.5.1 計器配置図
5.5.2 計器取付要領図··········································· 131······································· 131

6. 計装配線配管工事（現場接続箱～現場計装機器）··················· 136

6.1 設計手順··················································· 136

6.2 設計項目··················································· 136

6.3 設計用図書················································· 137

6.4 設計······················································· 137

6.4.1 ケーブル仕様········································· 137

6.4.2 電気信号の区分······································· 137

6.4.3 電線管仕様及びサイズ································· 137

6.4.4 配線経路············································· 138

6.4.5 雷対策··············································· 140

6.4.6 電気障害防止対策
6.4.7 資材····································· 141················································· 145

6.5 設計図書の作成············································· 145

6.5.1 計装配線配管図······································· 145

6.5.2 計装配線接続表······································· 149

7. 導圧配管工事··················································· 151

7.1 設計手順··················································· 151

7.2 設計項目··················································· 151

7.3 設計用図書
7.4 設計················································· 151······················································· 152

7.4.1 計器マウント方式
7.4.2 導圧配管方式····································· 152········································· 153

7.4.3 圧力取出しノズルの方向及び計器取付位置
7.4.3.1 共通············································· 153

7.4.3.2 差圧式流量計
7.4.3.3 圧力計····································· 155··········································· 158

7.4.3.4 差圧式液面計····································· 160

7.4.3.5 計器取付位置及び導圧配管例
7.4.4 資材··············· 153······················· 161················································· 170

7.5 設計図書の作成············································· 186

8. 分析計配管工事················································· 192

8.1 設計手順··················································· 192

8.2 設計項目··················································· 192

8.3 設計用図書················································· 192

8.4 設計······················································· 193

8.4.1 設計範囲
8.4.2 分析計の配置············································· 193········································· 193

8.4.3 計器ベンダ図書の確認································· 193

8.4.4 サンプリング配管
8.4.5 資材····································· 194················································· 195

8.5 設計図書の作成············································· 195

8.5.1 分析計配管要領図····································· 195

8.5.2 分析計サンプリング配管布設図························· 199

9. トレース工事··················································· 200

9.1 設計手順··················································· 200

9.2 設計項目··················································· 200

9.3 設計用図書················································· 200

9.4 設計······················································· 201

9.4.1 熱源の選定··········································· 201

9.4.2 トレース方式········································· 202

9.4.2.1 スチームトレース································· 202

9.4.2.2 温水トレース····································· 205

9.4.2.3 電気トレース····································· 205

9.4.3 資材················································· 213

9.5 設計図書の作成············································· 213

9.5.1 トレース配管要領図··································· 213

9.5.2 スチーム供給配管図··································· 216

10. 計装供給空気配管工事·········································· 218

10.1 設計手順················································· 218

10.2 設計項目················································· 218

10.3 設計用図書··············································· 218

10.4 設計····················································· 219

10.4.1 計装供給空気配管の分配方式·························· 219

10.4.2 計装供給空気配管の減圧方式·························· 220

10.4.3 緊急時のバックアップ方式···························· 222

10.4.4 空気消費量、配管サイズ計算·························· 224

10.4.5 配管················································ 225

10.4.6 資材················································ 229

10.5 設計図書の作成··········································· 230

10.5.1 計装供給空気配管系統図
10.5.2 計装供給空気配管図11. 計装信号空気配管工事······························ 230·································· 230·········································· 236

11.1 設計手順················································· 236

11.2 設計項目················································· 236

11.3 設計用図書
11.4 設計··············································· 236····················································· 237

11.4.1 計装信号空気配管方式の選定·························· 237

11.4.2 計装信号空気配管サイジング·························· 239

11.4.3 配管················································ 240

11.4.4 資材················································ 242

11.5 設計図書の作成··········································· 248

11.5.1 計装信号空気配管系統図
11.5.2 計装信号空気配管図······························ 248·································· 248

12. 塗装、保温・保冷工事·········································· 251

13. その他計装工事関連図書········································ 251

第 3 編 計装工事資材の拾い出し······································ 252

1. 共通··························································· 252

2. 計器室内工事··················································· 252

2.1 計器室内機器据付用資材
2.2 計器室内配線用資材
3. ケーブルウエイ工事····································· 252········································· 253············································· 255

3.1 ケーブルダクト資材········································· 255

3.2 ケーブルラック資材········································· 257

3.3 ケーブルピット、トラフ、保護管（FEP 管）資材
3.4 ダクト、ラック用サポート
3.5 計器室引込み資材··············· 257··································· 257··········································· 257

4. 主ケーブル布設工事············································· 257

4.1 ケーブル··················································· 258

4.2 現場接続箱················································· 259

4.3 JB 据付用サポート·········································· 260

4.4 ケーブル保護管資材········································· 261

5. 現場計装盤・計器据付工事······································· 261

5.1 現場計装盤据付資材········································· 261

5.2 スタンション··············································· 261

5.3 計器取付資材··············································· 261

6. 計装配線配管工事（現場接続箱～現場計装機器）
6.1 ケーブル··················· 263··················································· 263

6.2 ケーブル保護管資材········································· 264

7. 導圧配管工事··················································· 266

8. 分析計配管工事················································· 266

9. トレース工事··················································· 268

10. 計装供給空気配管工事·········································· 271

10.1 パイプ及びパイプ継手····································· 271

10.2 端末資材（チューブ及びチューブ継手）····················· 271

11. 計装信号空気配管工事·········································· 273

12. 塗装、保温・保冷工事·········································· 274